text:
GitLab Documentation guidelines
GitLab's documentation is intended as the single source of truth (SSOT) for information about how to configure, use, and troubleshoot GitLab. The documentation contains use cases and usage instructions for every GitLab feature, organized by product area and subject. This includes topics and workflows that span multiple GitLab features, and the use of GitLab with other applications.
In addition to this page, the following resources can help you craft and contribute documentation:
- Style Guide - What belongs in the docs, language guidelines, Markdown standards to follow, and more.
- Structure and template - Learn the typical parts of a doc page and how to write each one.
- Documentation process.
- Markdown Guide - A reference for all Markdown syntax supported by GitLab.
- Site architecture - How https://docs.gitlab.com is built.
Source files and rendered web locations
Documentation for GitLab, GitLab Runner, Omnibus GitLab and Charts is published to https://docs.gitlab.com. Documentation for GitLab is also published within the application at
/help on the domain of the GitLab instance.
/help, only help for your current edition and version is included. Help for other versions is available at https://docs.gitlab.com/archives/.
The source of the documentation exists within the codebase of each GitLab application in the following repository locations:
|GitLab Runner
|Omnibus GitLab
Documentation issues and merge requests are part of their respective repositories and all have the label
Branch naming
The CI pipeline for the main GitLab project is configured to automatically run only the jobs that match the type of contribution. If your contribution contains only documentation changes, then only documentation-related jobs will be run, and the pipeline will complete much faster than a code contribution.
If you are submitting documentation-only changes to Runner, Omnibus, or Charts, the fast pipeline is not determined automatically. Instead, create branches for docs-only merge requests using the following guide:
|Branch name
|Valid example
|Starting with
|Starting with
|Ending in
Contributing to docs
Contributions to GitLab docs are welcome from the entire GitLab community.
To ensure that GitLab docs are current, there are special processes and responsibilities for all feature changes—i.e. development work that impacts the appearance, usage, or administration of a feature.
However, anyone can contribute documentation improvements that are not associated with a feature change. For example, adding a new doc on how to accomplish a use case that's already possible with GitLab or with third-party tools and GitLab.
Markdown and styles
GitLab docs uses GitLab Kramdown as its Markdown rendering engine. See the GitLab Markdown Guide for a complete Kramdown reference.
Adhere to the Documentation Style Guide. If a style standard is missing, you are welcome to suggest one via a merge request.
Folder structure and files
See the Structure section of the Documentation Style Guide.
Changing document location
Changing a document's location requires specific steps to ensure that
users can seamlessly access the new doc page, whether they are accessing content
on a GitLab instance domain at
/help or at https://docs.gitlab.com. Be sure to assign a
technical writer if you have any questions during the process (such as
whether the move is necessary), and ensure that a technical writer reviews this
change prior to merging.
If you indeed need to change a document's location, do not remove the old document, but instead replace all of its content with a new line:
This document was moved to [another location](path/to/new_doc.md).
path/to/new_doc.md is the relative path to the root directory
For example, if you move
doc/workflow/lfs/lfs_administration.md to
doc/administration/lfs.md, then the steps would be:
Replace the contents of
This document was moved to [another location](../../administration/lfs.md).
Find and replace any occurrences of the old location with the new one. A quick way to find them is to use
git grep. First go to the root directory where you cloned the
gitlabrepository and then do:
git grep -n "workflow/lfs/lfs_administration" git grep -n "lfs/lfs_administration"
NOTE: Note: If the document being moved has any Disqus comments on it, there are extra steps to follow documented just below.
Things to note:
- Since we also use inline documentation, except for the documentation itself,
the document might also be referenced in the views of GitLab (
app/) which will render when visiting
/help, and sometimes in the testing suite (
spec/). You must search these paths for references to the doc and update them as well.
- The above
git grepcommand will search recursively in the directory you run it in for
lfs/lfs_administrationand will print the file and the line where this file is mentioned. You may ask why the two greps. Since we use relative paths to link to documentation, sometimes it might be useful to search a path deeper.
- The
*.mdextension is not used when a document is linked to GitLab's built-in help page, that's why we omit it in
git grep.
- Use the checklist on the "Change documentation location" MR description template.
Alternative redirection method
You can also replace the content of the old file with a frontmatter containing a redirect link:
redirect_to: '../path/to/file/README.md'
It supports both full and relative URLs, e.g.
path/to/file.md. Note that any
*.md paths will be compiled to
NOTE: Note:
This redirection method will not provide a redirect fallback on GitLab
/help. When using
it, make sure to add a link to the new page on the doc, otherwise it's a dead end for users that
land on the doc via
Redirections for pages with Disqus comments
If the documentation page being relocated already has Disqus comments, we need to preserve the Disqus thread.
Disqus uses an identifier per page, and for https://docs.gitlab.com, the page identifier is configured to be the page URL. Therefore, when we change the document location, we need to preserve the old URL as the same Disqus identifier.
To do that, add to the frontmatter the variable
using the old URL as value. For example, let's say I moved the document
available under
https://docs.gitlab.com/my-old-location/README.html to a new location,
Into the new document frontmatter add the following:
disqus_identifier: 'https://docs.gitlab.com/my-old-location/README.html'
Note: it is necessary to include the file name in the
disqus_identifier URL,
even if it's
index.html or
Merge requests for GitLab documentation
Before getting started, make sure you read the introductory section "contributing to docs" above and the documentation workflow.
- Use the current merge request description template
- Label the MR
- Assign the correct milestone (see note below)
Documentation will be merged if it is an improvement on existing content, represents a good-faith effort to follow the template and style standards, and is believed to be accurate.
Further needs for what would make the doc even better should be immediately addressed in a follow-up MR or issue.
NOTE: Note:
If the release version you want to add the documentation to has already been
frozen or released, use the label
Pick into X.Y to get it merged into
the correct release. Avoid picking into a past release as much as you can, as
it increases the work of the release managers.
Every GitLab instance includes the documentation, which is available at
https://gitlab.example.com/help). For example, https://gitlab.com/help.
There are plans to end this practice and instead link out from the GitLab application to https://docs.gitlab.com URLs.
The documentation available online on https://docs.gitlab.com is continuously
deployed every hour from the
master branch of GitLab, Omnibus, and Runner. Therefore,
once a merge request gets merged, it will be available online on the same day.
However, they will be shipped (and available on
/help) within the milestone assigned
to the MR.
For instance, let's say your merge request has a milestone set to 11.3, which
will be released on 2018-09-22. If it gets merged on 2018-09-15, it will be
available online on 2018-09-15, but, as the feature freeze date has passed, if
the MR does not have a "pick into 11.3" label, the milestone has to be changed
to 11.4 and it will be shipped with all GitLab packages only on 2018-10-22,
with GitLab 11.4. Meaning, it will only be available under
/help from GitLab
11.4 onward, but available on https://docs.gitlab.com/ on the same day it was merged.
Linking to
When you're building a new feature, you may need to link the documentation
from GitLab, the application. This is normally done in files inside the
app/views/ directory with the help of the
help_page_path helper method.
In its simplest form, the HAML code to generate a link to the
/help page is:
= link_to 'Help page', help_page_path('user/permissions')
help_page_path contains the path to the document you want to link to with
the following conventions:
- it is relative to the
doc/directory in the GitLab repository
- the
.mdextension must be omitted
- it must not end with a slash (
Below are some special cases where should be used depending on the context. You can combine one or more of the following:
Linking to an anchor link. Use
anchoras part of the
= link_to 'Help page', help_page_path('user/permissions', anchor: 'anchor-link')
Opening links in a new tab. This should be the default behavior:
= link_to 'Help page', help_page_path('user/permissions'), target: '_blank'
Linking to a circle icon. Usually used in settings where a long description cannot be used, like near checkboxes. You can basically use any font awesome icon, but prefer the
= link_to icon('question-circle'), help_page_path('user/permissions')
Using a button link. Useful in places where text would be out of context with the rest of the page layout:
= link_to 'Help page', help_page_path('user/permissions'), class: 'btn btn-info'
Using links inline of some text.
Description to #{link_to 'Help page', help_page_path('user/permissions')}.
Adding a period at the end of the sentence. Useful when you don't want the period to be part of the link:
= succeed '.' do Learn more in the = link_to 'Help page', help_page_path('user/permissions')
/help tests
Several rspec tests
are run to ensure GitLab documentation renders and works correctly. In particular, that main docs landing page will work correctly from
For example, GitLab.com's
Docs site architecture
See the Docs site architecture page to learn how we build and deploy the site at https://docs.gitlab.com and to review all the assets and libraries in use.
Global navigation
See the Global navigation doc for information on how the left-side navigation menu is built and updated.
Previewing the changes live
NOTE: Note: To preview your changes to documentation locally, follow this development guide or these instructions for GDK.
The live preview is currently enabled for the following projects:
If your merge request has docs changes, you can use the manual
review-docs-deploy job
to deploy the docs review app for your merge request.
You will need at least Maintainer permissions to be able to run it.
NOTE: Note: You will need to push a branch to those repositories, it doesn't work for forks.
review-docs-deploy* job will:
- Create a new branch in the
gitlab-docsproject named after the scheme:
docs-preview-$DOCS_GITLAB_REPO_SUFFIX-$CI_MERGE_REQUEST_IID, where
DOCS_GITLAB_REPO_SUFFIXis the suffix for each product, e.g,
eefor EE,
omnibusfor Omnibus GitLab, etc, and
CI_MERGE_REQUEST_IIDis the ID of the respective merge request.
- Trigger a cross project pipeline and build the docs site with your changes.
In case the review app URL returns 404, this means that either the site is not
yet deployed, or something went wrong with the remote pipeline. Give it a few
minutes and it should appear online, otherwise you can check the status of the
remote pipeline from the link in the merge request's job output.
If the pipeline failed or got stuck, drop a line in the
#docs chat channel.
TIP: Tip: Someone with no merge rights to the GitLab projects (think of forks from contributors) cannot run the manual job. In that case, you can ask someone from the GitLab team who has the permissions to do that for you.
NOTE: Note: Make sure that you always delete the branch of the merge request you were working on. If you don't, the remote docs branch won't be removed either, and the server where the Review Apps are hosted will eventually be out of disk space.
Troubleshooting review apps
In case the review app URL returns 404, follow these steps to debug:
- Did you follow the URL from the merge request widget? If yes, then check if the link is the same as the one in the job output.
Did you follow the URL from the job output? If yes, then it means that
either the site is not yet deployed or something went wrong with the remote
pipeline. Give it a few minutes and it should appear online, otherwise you
can check the status of the remote pipeline from the link in the job output.
If the pipeline failed or got stuck, drop a line in the
#docschat channel.
Technical aspects
If you want to know the in-depth details, here's what's really happening:
- You manually run the
review-docs-deployjob in a merge request.
- The job runs the
scripts/trigger-build-docsscript with the
deployflag, which in turn:
- Takes your branch name and applies the following:
- The
docs-preview-prefix is added.
- The product slug is used to know the project the review app originated from.
- The number of the merge request is added so that you can know by the
gitlab-docsbranch name the merge request it originated from.
- The
- The remote branch is then created if it doesn't exist (meaning you can re-run the manual job as many times as you want and this step will be skipped).
- A new cross-project pipeline is triggered in the docs project.
- The preview URL is shown both at the job output and in the merge request widget. You also get the link to the remote pipeline.
- Takes your branch name and applies the following:
- In the docs project, the pipeline is created and it skips the test jobs to lower the build time.
- Once the docs site is built, the HTML files are uploaded as artifacts.
- A specific Runner tied only to the docs project, runs the Review App job
that downloads the artifacts and uses
rsyncto transfer the files over to a location where NGINX serves them.
The following GitLab features are used among others:
- Manual actions
- Multi project pipelines
- Review Apps
- Artifacts
- Specific Runner
- Pipelines for merge requests
We treat documentation as code, and so use tests in our CI pipeline to maintain the standards and quality of the docs. The current tests, which run in CI jobs when a merge request with new or changed docs is submitted, are:
docs lint: Runs several tests on the content of the docs themselves:
lint-doc.shscript checks that:
- All cURL examples use the long flags (ex:
--header, not
- The
CHANGELOG.mddoes not contain duplicate versions.
- No files in
doc/are executable.
- No new
README.mdwas added.
- All cURL examples use the long flags (ex:
- markdownlint.
- Nanoc tests, which you can run locally before
pushing to GitLab by executing the command
bundle exec nanoc check internal_links(or
internal_anchors) on your local
internal_linkschecks that all internal links (ex:
[link](../index.md)) are valid.
internal_anchorschecks that all internal anchors (ex:
[link](../index.md#internal_anchor)) are valid.
- If any code or the
doc/README.mdfile is changed, a full pipeline will run, which runs tests for
To help adhere to the documentation style guidelines, and improve the content added to documentation, consider locally installing and running documentation linters. This will help you catch common issues before raising merge requests for review of documentation.
The following are some suggested linters you can install locally and sample configuration:
markdownlint, which is the same as the test run in
NOTE: Note: This list does not limit what other linters you can add to your local documentation writing toolchain.
proselint checks for common problems with English prose. It provides a
plethora of checks that are helpful for technical writing.
proselint can be used on the command line, either on a single
Markdown file or on all Markdown files in a project. For example, to run
proselint on all
documentation in the
gitlab project, run the
following commands from within the
gitlab project:
cd doc
proselint **/*.md
proselint can also be run from within editors using plugins. For example, the following plugins
are available:
proselint configuration
All of the checks are good to use. However, excluding the
typography.symbols and
misc.phrasal_adjectives checks will reduce
noise. The following sample
proselint configuration disables these checks:
"checks": {
"typography.symbols": false,
"misc.phrasal_adjectives": false
A file with
proselint configuration must be placed in a
valid location. For example,
markdownlint checks that Markdown
syntax follows certain rules,
and is used by the
docs-lint test with a configuration file.
Our Documentation Style Guide and Markdown Guide
elaborate on which choices must be made when selecting Markdown syntax for GitLab
documentation. This tool helps catch deviations from those guidelines.
markdownlint can be used on the command line,
either on a single Markdown file or on all Markdown files in a project. For example, to run
markdownlint on all documentation in the
gitlab project,
run the following commands from within your
gitlab project root directory, which will
automatically detect the
.markdownlint.json config
file in the root of the project, and test all files in
/doc and its subdirectories:
markdownlint 'doc/**/*.md'
If you wish to use a different config file, use the
-c flag:
markdownlint -c <config-file-name> 'doc/**/*.md'
markdownlint can also be run from within text editors using plugins/extensions, such as:
It is best to use the same configuration file as what is in use in the four repos that are the sources for https://docs.gitlab.com. Each plugin/extension has different requirements regarding the configuration file, which is explained in each editor's docs.
markdownlint configuration
Each formatting issue that markdownlint checks has an associated
These rules are configured in the
.markdownlint.json files located in the root of
four repos that are the sources for https://docs.gitlab.com:
- https://gitlab.com/gitlab-org/gitlab/blob/master/.markdownlint.json
- https://gitlab.com/gitlab-org/gitlab-runner/blob/master/.markdownlint.json
- https://gitlab.com/gitlab-org/omnibus-gitlab/blob/master/.markdownlint.json
- https://gitlab.com/charts/gitlab/blob/master/.markdownlint.json
By default all rules are enabled, so the configuration file is used to disable unwanted rules, and also to configure optional parameters for enabled rules as needed. You can also check the issue that tracked the changes required to implement these rules, and details which rules were on or off when markdownlint was enabled on the docs.
Danger Bot
GitLab uses Danger for some elements in
code review. For docs changes in merge requests, whenever a change to files under
is made, Danger Bot leaves a comment with further instructions about the documentation
process. This is configured in the Dangerfile in the GitLab repo under


text:
Our trusted partner for cheap ferries is aferry.co.uk
Their cheap ferry ticket comparison engine searches over 70 European ferry companies with over 1,000 ferry routes. Whether you're looking for a single journey for one person or a family boarding with a car thy will find you the best cheap ferry ticket for you.
You will not only be spoilt for choice but will also discover ferry routes that you've never known before, but each ferry company has great deals & offers which they have handpicked just for you.

subset: commoncrawl


text:
Billionaire Red Bull Creator Dies
The Thai billionaire who created popular energy drink Red Bull three decades ago has died at 89. Chaleo Yoovidhya founded T.C. Pharmaceuticals, who first developed Red Bull — or as it's known in Thailand, Krathing Daeng.
Red Bull didn't become an international hit until Chaleo partnered with an Austrian company in 1984. In the time since then, Red Bull became the go-to for college students who can't stand to pop NoDoz straight — only recently being replaced by 5-Hour Energy shots.
So let's pour one out for Chaleo Yoovidhya. He helped keep us awake long, long after we should have been sleeping.
[Image via AP]


text:
The Guardian, By Jamie Doward
May 11, 2013
British psychologists are to say that current psychiatric diagnoses such as bipolar disorder are useless.
There is no scientific evidence that psychiatric diagnoses such as schizophrenia and bipolar disorder are valid or useful, according to the leading body representing Britain's clinical psychologists.
In a groundbreaking move that has already prompted a fierce backlash from psychiatrists, the British Psychological Society's division of clinical psychology (DCP) will on Monday issue a statement declaring that, given the lack of evidence, it is time for a "paradigm shift" in how the issues of mental health are understood.
The statement effectively casts doubt on psychiatry's predominantly biomedical model of mental distress – the idea that people are suffering from illnesses that are treatable by doctors using drugs. The DCP said its decision to speak out "reflects fundamental concerns about the development, personal impact and core assumptions of the (diagnosis) systems", used by psychiatry.
Dr Lucy Johnstone, a consultant clinical psychologist who helped draw up the DCP's statement, said it was unhelpful to see mental health issues as illnesses with biological causes.
"On the contrary, there is now overwhelming evidence that people break down as a result of a complex mix of social and psychological circumstances – bereavement and loss, poverty and discrimination, trauma and abuse," Johnstone said. The provocative statement by the DCP has been timed to come out shortly before the release of DSM-5, the fifth edition of the American Psychiatry Association's Diagnostic and Statistical Manual of Mental Disorders.
The manual has been attacked for expanding the range of mental health issues that are classified as disorders. For example, the fifth edition of the book, the first for two decades, will classify manifestations of grief, temper tantrums and worrying about physical ill-health as the mental illnesses of major depressive disorder, disruptive mood dysregulation disorder and somatic symptom disorder, respectively.
Some of the manual's omissions are just as controversial as the manual's inclusions. The term "Asperger's disorder" will not appear in the new manual, and instead its symptoms will come under the newly added "autism spectrum disorder".
The DSM is used in a number of countries to varying degrees. Britain uses an alternative manual, the International Classification of Diseases (ICD) published by the World Health Organisation, but the DSM is still hugely influential – and controversial.
The writer Oliver James, who trained as a clinical psychologist, welcomed the DCP's decision to speak out against psychiatric diagnosis and stressed the need to move away from a biomedical model of mental distress to one that examined societal and personal factors.


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Single sign-on roadmap
Updated: June 25, 2015
Applies To: Azure, Office 365, Power BI, Windows Intune
Single sign-on (SSO) allows you and your users to access Microsoft cloud services with your Active Directory corporate credentials. SSO requires both a security token service (STS) infrastructure and Active Directory synchronization.
You must complete the following steps in order to implement SSO:
Step 1: Prepare for single sign-on
Step 2: Set up your on-premises security token service
Step 3: Set up directory synchronization
Step 4: Verify single sign-on
Step 1: Prepare for single sign-on
To prepare, you must make sure your environment meets the requirements for SSO and verify that your Active Directory and Azure Active Directory tenant is set up in a way that is compatible with single sign-on requirements. For more information, see Prepare for single sign-on.
Step 2: Set up your on-premises security token service
After you have prepared your environment for single sign-on, you will need to set up a new on-premises STS infrastructure to provide your local and remote Active Directory users with single sign-on access to the cloud service. If you currently have an STS in your production environment, you can use it for single sign-on deployment rather than setting up a new infrastructure as long as it is supported by Azure AD.
Currently, Azure AD supports either of the following security token services:
Active Directory Federation Services (AD FS)
For more information about how to get started with setting up an AD FS STS, follow the steps provided in Checklist: Use AD FS to implement and manage single sign-on.
Shibboleth Identity Provider
For more information about how to get started with setting up a Shibboleth STS, follow the steps provided in Use Shibboleth Identity Provider to implement single sign-on.
Other third-party identity providers
For more information about how to get started with setting up third-party identity providers for single sign-on, see Azure Active Directory federation compatibility list: third-party identity providers that can be used to implement single sign-on.
Step 3: Set up directory synchronization
In order for single sign-on to work properly, you must set up Active Directory synchronization as well. This includes preparing for, activating, installing a tool, and verifying directory synchronization. After you have verified directory synchronization, you activate your synced users. Using single sign-on and directory synchronization together ensures that user identities are represented correctly in the cloud service.
For more information about how to get started with setting up directory synchronization, follow the steps provided in Directory synchronization roadmap.
Step 4: Verify single sign-on
After you finish setting up your Active Directory synchronization environment, you now need to verify that your STS is functioning as expected and that single sign-on was set up correctly for your cloud service.
For more information, see either Verify and manage single sign-on with AD FS or Verify single sign-on with Shibboleth, depending on the STS type you are setting up.


text:
Being Anglican
Anglicans are Christians, members of the universal church, valuing what is distinctive about the worldwide Anglican Communion.
Anglicans seek to work with the Holy Spirit to overcome divisions between churches, so that all Christians may be one.
Worshiping God
Worship of God is central to Anglicans.
There is variety in Anglican worship: contemporary and informal, or traditional and formal. A special place is given to the Eucharist, in which we share the sacrament (the visible sign with spiritual meaning) of the body and blood of Christ.
Reading and meditating on the Bible plays a major part in Anglican life and belief.
Significant Facts
The Lambeth Conference, a gathering of bishops which meets every ten years, has identified as significant to Anglicans in the quest for Christian unity
- The Bible
- The Nicene Creed (statement of faith)
- The sacraments of Baptism and Eucharist
- The role of Bishops
- Anglicans bring together traditions from the early centuries of Christianity, ancient Celtic Christianity, medieval Catholicism and the European Reformation of the sixteenth century.
- The name 'Anglican' indicates roots in the Church of England and still involves being in communion with the Archbishop of Canterbury.
Contemporary Picture
- Today, Anglicans embrace a variety of languages and cultures from many different parts of the world, giving distinctive features to our worship, church life and theology.
- Anglicans today are actively exploring how our own land and multicultural heritage enrich Australian Anglicanism.
- Anglicans world-wide are seeking to reflect something of the unity-in-diversity of God, who is Father, Son and Holy Spirit: three persons in one God.
The above statements were formulated by The Anglican Diocese of Brisbane.
Professional Standards Information Sexual Abuse Line 1800 242 544 (landlines only) or 07 3835 2216


text:
The U.S. Federal Communications Commission has ordered Comcast to stop interfering with peer-to-peer traffic on its broadband network, with officials there saying the cable provider was "invasive" in its network traffic management.
In a victory for net neutrality advocates, the FCC on Friday voted 3-2 to order Comcast to stop slowing P-to-P traffic by the end of the year and to come up with a new network management plan. If Comcast refuses, the company could be subject to an injunction and other regulatory penalties.
Comcast's traffic management, unveiled by press reports in late 2007, was "discriminatory and not narrowly tailored to address Comcast's concern about network congestion," said FCC member Michael Copps. "Today, we choose the open road."
Comcast didn't tell its subscribers that it was slowing BitTorrent and other P-to-P traffic until the press reports. As expected, FCC Chairman Kevin Martin, a Republican, joined the commission's two Democrats to approve the order.
"Would you be OK with the post office opening your mail, deciding they didn't want to bother delivering it, and hiding that fact by sending it back to you stamped, 'address unknown — return to sender?'" Martin said. "Or, if they opened letters mailed to you, decided that because the mail truck is full sometimes, letters to you could wait, and then hid both that they read your letters and delayed them? Unfortunately, that is exactly what Comcast was doing with their subscribers' Internet traffic."
Comcast continued to insist it was taking "carefully limited" network management measures. Four months ago, Comcast set a goal of creating a new network management policy by the end of the year, noted Sena Fitzmaurice, senior director of corporate communications and government affairs.
"We are gratified that the commission did not find any conduct by Comcast that justified a fine and that the deadline established in the order is the same self-imposed deadline that we announced four months ago," Fitzmaurice said. "On the other hand, we are disappointed in the commission's divided conclusion because we believe that our network management choices were reasonable, wholly consistent with industry practices and that we did not block access to Web sites or online applications, including peer-to-peer services."
The FCC order raises "a variety of substantive legal questions," and Comcast is considering all its legal options, she added.
The commission's two other Republicans argued that the FCC is interfering with Comcast's ability to protect its broadband network. Evidence gathered in the case is conflicting, and the decision may cause network gridlock, said FCC member Robert McDowell.
"The fact is the FCC does not know what Comcast did and did not do," he said. "Ironically, today's decision … may result in slow speeds for 95 percent of Internet users."
The order opens up the Internet to massive new regulation, McDowell added. Broadband providers may have to ask the FCC for permission to roll out new network management plans, he said.
In 2005, the FCC adopted Internet policy principles telling consumers they have a right to unfettered access to legal Web applications, devices and services of their choice. But those were guidelines, and the FCC lacks the authority to take action against Comcast, McDowell said. "We do not have any rules … to enforce," he said.
Comcast has also questioned whether the FCC has the authority to regulate its network management techniques.
But commissioners voting against Comcast said the FCC has consistently asserted authority to regulate broadband networks, and Friday's decision focuses narrowly on one provider's specific actions.
"If we aren't going to stop a company that is looking inside its subscribers' communications … blocking that communication when it uses a particular application regardless of whether there is congestion on the network, hiding what it is doing by making consumers think the problem is their own, and lying about it to the public, what would we stop?" Martin said.
Comcast interfered with people watching movie trailers, updating online game clients and downloading open-source software available on P-to-P networks, said Dana Shaffer, chief of the FCC's Wireline Competition Bureau.
"Comcast's practices are not minimally intrusive, but invasive," she said.
The Associated Press, in late 2007, reported that Comcast was slowing BitTorrent and some other traffic without telling its customers. Consumer rights groups Public Knowledge and Free Press, along with online video distributor Vuze, filed complaints with the FCC.
Comcast has said it throttles P-to-P traffic only during times of peak congestion, but Martin and a study from the Max Planck Institute for Software Systems in Germany have contended that Comcast slows BitTorrent traffic during off-peak hours as well.
Only 6 to 7 percent of Comcast subscribers use P-to-P services in a typical week, but one-half to two-thirds of the upstream traffic on its network comes from P-to-P, Fitzmaurice said. About 90 percent of P-to-P sessions on the Comcast network are unaffected by traffic management, she added.


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Custom MMIC, (www.CustomMMIC.com), a developer of performance driven monolithic microwave integrated circuits (MMICs), is offering a new device from its growing MMIC design library. The CMD162 is a GaAs MMIC low-noise amplifier (LNA) chip for applications from 26 to 34 GHz. Optimized for 30 GHz satellite communications, the CMD162 boasts a typical noise figure of 1.7 dB with a small-signal gain of 22 dB and an output 1 dB compression point of +7 dB. This amplifier delivers high performance with high efficiency, reducing typical industry DC power dissipation for a device in this frequency band from approximately 340 mW down to 50 mW.
The CMD162 also offers subsystem and device designers a key cost reduction attribute. Implementation is simplified since the device only requires positive drain and gate voltages of +2 V, thereby eliminating the negative voltages and sequencer circuits commonly associated with LNAs in this frequency range. The CMD162 can be biased with a drain voltage ranging from +1 to +4 V and a gate voltage ranging from 0 to +3 V.
The amplifier die measures 2.3 x 1.3 mm, includes gold backside metallization, and has full nitride passivation for increased reliability and moisture protection. It can handle input signal levels to +20 dBm. The GaAs MMIC amplifier has typical input return loss of 18 dB and typical output return loss of 20 dB, both at 30 GHz. It is a much smaller, lower-cost alternative to hybrid LNAs for this frequency range, and is uniquely suited for both narrowband and broadband applications requiring small size and low current consumption, including phased-array radar and point-to-point microwave radio systems.


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Entry by the School front Entrance.
Goalball is great fun, good exercise, and social We are a friendly group who play Goalball seriously for fun. We welcome new players of any age or ability whether Novice or Expert so why not give us and Goalball a try.
Try Goalball with the Croysutt Warriors!
Time: 6:00 pm to 9:00 pm
Date: Every Monday
Venue: Harris Invictus Academy, 88 London Road, Croydon, CR0 2TB
Entry by the School front Entrance.
For more information and to confirm the event. please
Contact: Robin Tel 07889648925 , Tommy 0740343536 or email email@example.com
See us on Facebook at Croysutt WarriorsGoalball
Twitter @croysuttwarrior
Metro would always advise to phone or email the event contacts to confirm there have been no last-minute changes or cancellations.
What is goalball?
Goalball is an exciting, indoor, 3-aside team sport, of attack and defend – with
a unique twist!
The sport was originally devised in 1946 to help rehabilitate soldiers who had lost
their sight during the war. It has been played throughout the world ever since up to
the highest level as a Paralympic sport, by people who have visual impairments.
Goalball is a truly inclusive sport as fully sighted players can also play alongside
those with visual impairment as all of the players wear eyeshades so that nobody
can see the ball. Players, therefore, have to rely entirely on their other senses. It is
suitable for all ages and abilities
The ball contains internal bells so players are able to track its movement by its sound. The court is marked out with tactile lines so players can feel where they are.
The idea of the game is quite simply to score goals by bowling the ball along the floor, past the opposing team.
Goalball sessions are currently running at the Sir Philip Game Centre in Croydon for
further details please email firstname.lastname@example.com or call Robin on
Anyone who wants to get involved in the sport please visit our website
www.goalballuk.com or email us on firstname.lastname@example.com
Metro Blind Sports Social Networks
Get all the latest blind & partially sighted event information & news as soon as we do!
Metro Blind Sport: Facebook |Twitter |Instagram | LinkedIn


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- About the IACA
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Illinois Art Fair Directory
This directory has been developed to help artists find art fairs to sell and promote their work. In addition, both Illinoisans and visitors can locate art fairs and festivals in every region of the state. Whether an artist or an arts enthusiast, the Arts Council Agency hopes you find the Illinois Art Fair Directory a valuable resource. Available online only, at www.illinoisartfairdirectory.org.


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French energy giant Total has agreed to pay nearly $400 million to U.S. authorities after acknowledging that it paid massive bribes to secure drilling rights in Iran, and the company's chief executive may face a criminal trial in France as well.
Total (TOT) will pay $245 million to the Justice Department as part of a deferred-prosecution agreement, and $153 million to the Securities and Exchange Commission. The case was developed in cooperation with French authorities, who have requested that Total CEO and chairman Christophe de Margerie and two other individuals "be referred to the Criminal Court for violations of French law, including France's foreign bribery law," the DOJ said.
A statement from France's prosecutor of the republic identified those two individuals as Bijan Dadfar and Abbas Yazdi.
Total CFO Patrick de La Chevardière said in a statement that the company "look[s] forward to continuing our work and... demonstrating our strong commitment to ensuring ethical and legal compliance with laws around the world."
Total acknowledged that the allegations from the Department of Justice are "true and accurate," according to the deferred-prosecution agreement, but said it "reaffirms that it has not committed any offense under applicable French law."
"In the event of a trial, Total and its chief executive for the Middle East at the time will argue that the behavior that they are accused of was completely legal under French law," Total said in a statement to French news agency AFP.
De Margerie formerly served as president of Total's Middle East operations.
Related: Ralph Lauren admits bribery at Argentina subsidiary
The Justice Department said Total paid $60 million in bribes to a government official in Iran between 1995 and 2004 in an effort to secure oil and gas development rights in the country. Total funneled the money to the official via "consulting agreements" with intermediaries.
"Total mischaracterized the unlawful payments as 'business development expenses' when they were, in fact, bribes designed to corruptly influence a foreign official," the DOJ said.
Total reaped more than $150 million in profits as a result of the bribes, according to the SEC.
The charges in the U.S. case will be dismissed after three years provided Total adheres to terms of the deferred-prosecution agreement, including the implementation of an enhanced compliance program and the appointment of an independent monitor.
U.S. officials have stepped up enforcement of the Foreign Corrupt Practices Act in recent years.
Germany's Siemens paid $800 million to the DOJ and SEC as part of a global bribery case in 2008. Halliburton and KBR paid $579 million in 2009 in connection with bribery allegations in Nigeria, while the United Kingdom's B.A.E. paid $400 million to the DOJ in 2010 after being accused of making false statements about its anti-corruption efforts to U.S. authorities.
CNN's Carol Cratty contributed reporting from Washington.


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Home > Living as a Christian
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"Man who is born of woman is of few days and full of trouble" (Job 14:1). We can especially appreciate these words when we think of the suffering endured by the one who spoke them. Different people deal with different problems and afflictions, and it seems that some suffer more hardships than others do. But we all know by personal experience and from the experiences of those we know, that Job's statement is true.
Troubles concern us, not just because hardship itself is a burden, but also because affliction can lead to spiritual temptations. We may be tempted to feel that our trials justify committing sin. We may become so discouraged that we blame God for our troubles, lose faith in Him, or begin to doubt His goodness and mercy. As Job's wife said, "Curse God and die" (Job 2:9).
The purpose of this study is to offer Bible answers to questions people often ask about suffering. Why do people suffer? Can good come from suffering? Is it possible to endure affliction with patience and faithfulness? How can God give us strength to endure our hardships and overcome our temptations? What does the Bible say?
There are several reasons, not just one reason, why people suffer.
King Saul lived a miserable life and eventually was slain because he had rebelled against God (1 Chron. 10:13,14).
Judas killed himself because he had betrayed Jesus (Matthew 27:3-5).
Likewise today, alcoholics may develop disease, thieves may be imprisoned, etc.
Some people think this is the only reason people ever suffer, but we will see that it is not.
This may result from cruelty or accident, as when innocent bystanders are killed by a drunken driver, or when a thief violently attacks his victims.
In other cases wicked people may harm righteous people because they resent them. This kind of religious persecution is described in many verses.
1 Peter 2:19-23 - Jesus is an example of one who committed no sin at all, yet He was persecuted and killed by wicked men. So we may follow His example and suffer, not for our faults, but when we do good.
John 15:18-20 - The treatment Jesus received should warn us of the treatment we can expect. The world hated Him and persecuted Him, and it will do the same to His servants.
2 Corinthians 11:23-26 - Paul's life shows that Jesus' followers truly often are persecuted.
2 Timothy 3:10-12 - All who live godly in Christ shall suffer persecution.
(See also 1 Peter 4:12-16; Heb. 11:35-38; 1 Thess. 3:2-4; Acts 14:22; John 16:33; Gen. 50:20)
God originally placed Adam and Eve in a state of bliss with no problems of any kind. But He warned them of the consequences of sin. When they sinned anyway, He decreed they would endure pain, suffering, hardship, and eventual death (Gen. 3:16-19). All people since that time have endured these same problems. In particular, because of Adam, all people die (1 Cor. 15:22; Heb. 9:27).
Much of the suffering people endure, therefore, cannot be attributed to any particular sin committed by anyone now living. It is just the common lot of mankind because sin is in the world.
This does not mean, as some teach, that people today are born guilty of Adam's sin or will be eternally punished for it (Ezek. 18:20; 2 Cor. 5:10). But we do suffer in this life because of it.
Job 1:1-2:10 expressly states that Job's suffering was a temptation from Satan. He hoped that, because he was suffering, Job would turn away from God.
Many other passages teach that Satan is responsible for the suffering of other people. (See 2 Cor. 12:7-10; Luke 13:16; Acts 10:38).
Some people think that only wicked people suffer, but God is on the side of the righteous and will remove all their troubles. It follows that, if a person is suffering, he must have committed some sin he should repent of.
This was the theory of Job's friends (Job 4:7-9); disproving this idea is a main theme of that book. This same false doctrine is taught by many "faith healers" who teach people that God must remove all their problems if they are right with Him.
But we have learned that even righteous people suffer. This is important for the following reasons:
* We should not conclude that we have been guilty of sin every time we have a problem. Maybe we are suffering because of sin, so we should examine our lives. But maybe we are suffering for other reasons, perhaps because we are righteous.
* We should surely never reject a Bible teaching just because it may lead to suffering. If all suffering was the result of our own sin, and if a course of action led to suffering, then we would conclude it was a sinful act. But we have learned that godly people often suffer for doing right.
* We should not become Christians thinking it will automatically solve all our problems. If this is our motive, we may fall away when the hardships come.
But the main lesson to learn is the next point:
If we believe that all suffering results from a person's own sin, and if we see good people suffering, we may be tempted to blame God or to think He is not keeping His promises. But we have learned that all people suffer, whether or not they are righteous.
The command to endure suffering is just another part of a Christian's life, like the command to study the Bible, pray, worship, etc. Faithful Christians of all ages have suffered; we are not the only ones. We should expect suffering to come, so our faith will not be shaken when it does.
The ultimate and primary blame for suffering rests on Satan who tempts people to sin and thereby brought sin into the world. The secondary blame rests upon people, ourselves included, who have given in to temptation and committed sin that led to suffering.
Yes, God did create suffering as a punishment for sin, but only after He had given people a life without problems and had warned them of the consequences of sin. When they chose to sin, He should no more be blamed for punishing them than a parent should be blamed when he must punish a rebellious child. (Cf. James 1:13,15.)
Remember, if you blame God and reject Him because you are suffering, then you are doing exactly what Satan wants you to do. He has defeated you! The only way to defeat Satan and really overcome hardship is to maintain your faithfulness to God in spite of it.
"It is good for me that I have been afflicted" (Psa. 119:71). Usually when we suffer we can only see the problems involved. Surely if we commit sin as a result, then the suffering is harmful. But if we remain faithful, there are favorable results that can occur. Consider a few.
1 Peter 1:6,7 - As gold is purified by passing through fire, so the genuineness of our faith is proved by trials. If suffering was limited to sinners and Christians never suffered, all people would want to be Christians, not because they really loved God, but just to avoid earthly problems.
The fact that Christians suffer too means that suffering "separates the men from the boys" - it shows who is willing to remain faithful even when it is hard to do so. (Acts 5:40-42; 1 Cor. 11:19; 1 Peter 4:12)
James 1:2-4 - Count it joy when we face trials (hardly the natural reaction), because this leads to patience and completeness in God's service. Whoever developed patience when his patience was never tried?
Romans 5:3-5 - Rejoice in tribulations because they work steadfastness, approvedness, and hope.
Even in the physical realm, which bones and muscles are the strongest? The ones that face the most hardship. If you lay a block of ice and a block of clay in the sun, one is melted and the other is hardened. The same circumstance produces opposite results.
The story is told of two sons of an alcoholic. One son became a drunkard, the other became a teetotaler. Both explained their conduct the same way: "What can you expect with a father like mine?" The same problem produced opposite results.
Trials defeat some people but strengthen others. It depends on how we deal with them.
2 Corinthians 1:8-10 - Affliction taught Paul not to trust in himself, but in God. God has repeatedly allowed countries to face wars, famines, and hardships when they became independent and failed to trust Him. Often this shows people their need for God.
2 Corinthians 12:7-10 - Paul's "thorn in the flesh" was a messenger from Satan, yet God allowed it to remain because it kept Paul from becoming too proud over the many revelations he had received. From weaknesses, God can produce great strength.
Genesis 50:20 - Joseph explained that his brothers had mistreated him, but God used that as a means to save the family from famine.
Satan puts trials in our lives to harm us. Yet one of the greatest demonstrations of God's power is His ability to take those problems and use them to accomplish good. The greatest example of this is the death of Christ. Satan intended it as a defeat for God and all mankind, yet it ended up as the salvation of all mankind. (1 Peter 2:21-24)
Think for a moment of the really important things in life. How many of them are accomplished without hardship? Birth of a baby? Working to care for our families? Our eternal salvation? Suffering is an inherent part of everything good!
So Satan sends trials to harm us, but God can make them come out in the end for our good (Romans 8:28). But this works only if we remain faithful.
When facing hardship we may think, "I just can't hold out." We may convince ourselves that, to expect someone to continue under our circumstances without sinning, would be expecting the impossible. So we may justify ourselves for disobeying God. But consider the Bible teaching that we can endure.
1 Corinthians 10:13 - God will not allow you to face a temptation that is beyond your ability to endure. Every temptation will be accompanied by a way of escape so you can endure it.
This means we can endure every trial without sinning. If you think you "can't do" what God said to do, or if you ever justify disobeying God, you have believed the Devil's lie. What we need to do is to quit looking for excuses and look instead for the way of escape!
Psalm 34:19 - "Many are the afflictions of the righteous; but the Lord delivers him out of them all." God may not remove all the afflictions, but He makes sure we are able to endure them faithfully - all of them.
Romans 8:35-39 - No temptation or trial can separate us from God. In them all, we are "more than conquerors." If we endured the temptation without sinning, we would just be "conquerors." But we are more than conquerors because the problem can actually make us better people. (See also 1 Pet. 5:8,9; James 4:7; Eph. 6:10-18; Prov. 24:10.)
Not only does the Bible promise that we can endure faithfully, it gives us examples of many people who DID so. If they did, we can too.
James 5:10,11 - Job and Old Testament prophets are our examples of suffering. Have we suffered as much as Job? Surely not. Yet he remained faithful and so can we.
2 Timothy 1:8 - Paul suffered great hardship for the Lord, and we should share in those sufferings. If he endured without falling away, we can too. He is the example we should imitate (1 Corinthians 11:1).
Hebrews 12:1-4 - Jesus (and faithful Old Testament characters) are witnesses to what we can do under trying circumstances. Our temptations are no worse than theirs. All these examples show that God will keep His promises to help His people endure faithfully. (1 Pet. 2:19-23)
"God is our refuge and strength. A very present help in trouble" (Psalm 46:1). God has promised to help us endure, but we must make use of the help He provides. Let us summarize a few of the ways God helps.
Romans 15:4 - "...through patience and comfort of the scriptures we might have hope." We have already learned several ways the scriptures comfort and strengthen us when we are suffering:
* They help us understand that we will have to suffer, but good can result from our suffering.
* They give us assurance that we can endure like others have.
* They give evidence of God's wisdom, power, and faithfulness to his promises. This strengthens our faith that God can and will help us endure.
But the Bible gives us none of this help unless we regularly study it.
James 5:13 - "Is anyone among you suffering? Let him pray."
Philippians 4:6,7 - "Be anxious for nothing, but in everything by prayer and supplication, with thanksgiving, let your requests be made known unto God."
Job 1:20 - When Job suffered, he went to God in worship. Far too often when we suffer, we do the opposite. We neglect to worship, because we don't feel like it.
(1 Peter 5:7; Matt. 7:7ff)
These passages do not promise that God will remove our problem, but they do promise He will provide the strength we need to be faithful despite the problem. Jesus and Paul both prayed about problems, and God answered their prayers, but the problem was not removed. Instead, God gave them strength to endure (Matt. 26:36-46; 2 Cor. 12:7-10).
2 Corinthians 1:3,4 - Not only can God comfort us, so can other Christians. And we should strive to comfort others.
Galatians 6:2 - "Bear one another's burdens." We should never allow another Christian to suffer alone through serious problems, if there is any way we can help.
One of the best places to get encouragement in time of trouble is the public worship assemblies (Hebrews 10:24,25). Again, however, we must come to the assemblies and talk to other Christians to gain the help we need. (See also 1 Cor. 12:26; 1 Thess. 5:11,14.)
Romans 8:16-18 - We are heirs of God if we suffer with Jesus. The sufferings of this life are unworthy to even be compared with the future glory awaiting us.
James 1:12 - The man who endures is blessed, because the result will be a crown of life.
Matthew 5:10-12 - Rejoice and be glad (don't gripe and complain) when you are persecuted, because you are suffering as God's people always have. And great is your reward in heaven. (2 Cor. 4:16,17; 2 Tim. 1:11,12; 2:12; 1 Peter 1:3-7; 4:13)
Faithful Christians will suffer. Yet the Christian's life is still the best, because only faithful Christians have the assurance that we can endure, that God will help us, that the result will be for our good, and that in the end we will have eternal life.
"I can do all things through Christ who strengthens me" - Philippians 4:13. (See also Psalm 23.)
Copyright 1998,David E. Pratte; gospelway.com
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Tuesday, 6 June 2023
C2 June Final Marks
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Hello everyone! This is the blog for the C1 and C2 classes! I'll be posting some activities / videos / homework / pieces of writing and many other interesting resources. You'll be able to find some websites and other useful material. Visit it regularly, please!
Personal Identification, Physical Aspect, Character, Personality , ( activity ), ( activity , key ) Home, Neighbourhood, City , Money ( ...


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Take the online course on MyEducator: SEM Online 3 credit Graduate Course Invitation Video
Confirmatory Factor Analysis (CFA) is the next step after exploratory factor analysis to determine the factor structure of your dataset. In the EFA we explore the factor structure (how the variables relate and group based on inter-variable correlations); in the CFA we confirm the factor structure we extracted in the EFA.
- LESSON: Confirmatory Factor Analysis
- VIDEO TUTORIAL: CFA part 1
- VIDEO TUTORIAL: CFA part 2
Do you know of some citations that could be used to support the topics and procedures discussed in this section? Please email them to me with the name of the section, procedure, or subsection that they support. Thanks!
Model Fit
- VIDEO TUTORIAL: Model Fit Thresholds
Model fit refers to how well our proposed model (in this case, the model of the factor structure) accounts for the correlations between variables in the dataset. If we are accounting for all the major correlations inherent in the dataset (with regards to the variables in our model), then we will have good fit; if not, then there is a significant "discrepancy" between the correlations proposed and the correlations observed, and thus we have poor model fit. Our proposed model does not "fit" the observed or "estimated" model (i.e., the correlations in the dataset). Refer to the CFA video tutorial for specifics on how to go about performing a model fit analysis during the CFA.
There are specific measures that can be calculated to determine goodness of fit. The metrics that ought to be reported are listed below, along with their acceptable thresholds. Goodness of fit is inversely related to sample size and the number of variables in the model. Thus, the thresholds below are simply a guideline. For more contextualized thresholds, see Table 12-4 in Hair et al. 2010 on page 654. The thresholds listed in the table below are from Hu and Bentler (1999).
Modification indices
Modification indices offer suggested remedies to discrepancies between the proposed and estimated model. In a CFA, there is not much we can do by way of adding regression lines to fix model fit, as all regression lines between latent and observed variables are already in place. Therefore, in a CFA, we look to the modification indices for the covariances. Generally, we should not covary error terms with observed or latent variables, or with other error terms that are not part of the same factor. Thus, the most appropriate modification available to us is to covary error terms that are part of the same factor. The figure below illustrates this guideline - however, there are exceptions. In general, you want to address the largest modification indices before addressing more minor ones. For more information on when it is okay to covary error terms (however, some argue that there are never appropriate reasons to covary errors), refer to David Kenny's thoughts on the matter: David's website, or to the very helpful article: Hermida, R. 2015. "The Problem of Allowing Correlated Errors in Structural Equation Modeling: Concerns and Considerations," Computational Methods in Social Sciences (3:1), p. 5.
Standardized Residual Covariances
Standardized Residual Covariances (SRCs) are much like modification indices; they point out where the discrepancies are between the proposed and estimated models. However, they also indicate whether or not those discrepancies are significant. A significant standardized residual covariance is one with an absolute value greater than 2.58. Significant residual covariances significantly decrease your model fit. Fixing model fit per the residuals matrix is similar to fixing model fit per the modification indices. The same rules apply. For a more specific run-down of how to calculate and locate residuals, refer to the CFA video tutorial. It should be noted however, that in practice, I never address SRCs unless I cannot achieve adequate fit via modification indices, because addressing the SRCs requires the removal of items.
Validity and Reliability
- VIDEO TUTORIAL: Testing Validity and Reliability in a CFA
It is absolutely necessary to establish convergent and discriminant validity, as well as reliability, when doing a CFA. If your factors do not demonstrate adequate validity and reliability, moving on to test a causal model will be useless - garbage in, garbage out! There are a few measures that are useful for establishing validity and reliability: Composite Reliability (CR), Average Variance Extracted (AVE), Maximum Shared Variance (MSV), and Average Shared Variance (ASV). The video tutorial will show you how to calculate these values. The thresholds for these values are as follows:
Convergent Validity
Discriminant Validity
- Square root of AVE greater than inter-construct correlations
If you have convergent validity issues, then your variables do not correlate well with each other within their parent factor; i.e, the latent factor is not well explained by its observed variables. If you have discriminant validity issues, then your variables correlate more highly with variables outside their parent factor than with the variables within their parent factor; i.e., the latent factor is better explained by some other variables (from a different factor), than by its own observed variables.
If you need to cite these suggested thresholds, please use the following:
- Hair, J., Black, W., Babin, B., and Anderson, R. (2010). Multivariate data analysis (7th ed.): Prentice-Hall, Inc. Upper Saddle River, NJ, USA.
AVE is a strict measure of convergent validity. Malhotra and Dash (2011) note that "AVE is a more conservative measure than CR. On the basis of CR alone, the researcher may conclude that the convergent validity of the construct is adequate, even though more than 50% of the variance is due to error." (Malhotra and Dash, 2011, p.702).
- Malhotra N. K., Dash S. (2011). Marketing Research an Applied Orientation. London: Pearson Publishing.
Here is an updated video that uses the most recent Stats Tools Package, which includes a more accurate measure of AVE and CR.
- VIDEO TUTORIAL: SEM Series (2016) 5. Confirmatory Factor Analysis Part 2
Common Method Bias (CMB)
- VIDEO TUTORIAL: Zero-constraint approach to CMB
- REF: Podsakoff, P.M., MacKenzie, S.B., Lee, J.Y., and Podsakoff, N.P. "Common method biases in behavioral research: a critical review of the literature and recommended remedies," Journal of Applied Psychology (88:5) 2003, p 879.
Common method bias refers to a bias in your dataset due to something external to the measures. Something external to the question may have influenced the response given. For example, collecting data using a single (common) method, such as an online survey, may introduce systematic response bias that will either inflate or deflate responses. A study that has significant common method bias is one in which a majority of the variance can be explained by a single factor. To test for a common method bias you can do a few different tests. Each will be described below. For a step by step guide, refer to the video tutorials.
Harman's single factor test
- It should be noted that the Harman's single factor test is no longer widely accepted and is considered an outdated and inferior approach.
A Harman's single factor test tests to see if the majority of the variance can be explained by a single factor. To do this, constrain the number of factors extracted in your EFA to be just one (rather than extracting via eigenvalues). Then examine the unrotated solution. If CMB is an issue, a single factor will account for the majority of the variance in the model (as in the figure below).
Common Latent Factor
This method uses a common latent factor (CLF) to capture the common variance among all observed variables in the model. To do this, simply add a latent factor to your AMOS CFA model (as in the figure below), and then connect it to all observed items in the model. Then compare the standardised regression weights from this model to the standardized regression weights of a model without the CLF. If there are large differences (like greater than 0.200) then you will want to retain the CLF as you either impute composites from factor scores, or as you move in to the structural model. The CLF video tutorial demonstrates how to do this. This approach is taken in this article:
- Serrano Archimi, C., Reynaud, E., Yasin, H.M. and Bhatti, Z.A. (2018), "How perceived corporate social responsibility affects employee cynicism: the mediating role of organizational trust", Journal of Business Ethics, Vol. 151 No. 4, pp. 907-921.
Marker Variable
This method is simply an extended, and more accurate way to do the common latent factor method. For this method, just add another latent factor to the model (as in the figure below), but make sure it is something that you would not expect to correlate with the other latent factors in the model (i.e., the observed variables for this new factor should have low, or no, correlation with the observed variables from the other factors). Then add the common latent factor. This method teases out truer common variance than the basic common latent factor method because it is finding the common variance between unrelated latent factors. Thus, any common variance is likely due to a common method bias, rather than natural correlations. This method is demonstrated in the common method bias video tutorial.
Zero and Equal Constraints
- VIDEO TUTORIAL: Specific Bias 2017
The most current and best approach is outlined below. Here is an article that recommends this approach (pg. 20):
- Simmering, M. J., Fuller, C. M., Richardson, H. A., Ocal, Y., & Atinc, G. M. (2015). Marker variable choice, reporting, and interpretation in the detection of common method variance: A review and demonstration. Organizational Research Methods, 18(3), 473-511.
- Do an EFA, and make sure to include "marker" or specific bias (SB) constructs.
- Specific bias constructs are just like any other multi-item constructs but measure specific sources of bias that may account for shared variance not due to a causal relationship between key variables in the study. A common one is Social Desirability Bias.
- Do the CFA with SB constructs covaried to other constructs (this looks like a normal CFA).
- Assess and adjust to achieve adequate goodness of fit
- Assess and adjust to achieve adequate validity and reliability
- Add a common latent factor (CLF), sometimes called an unmeasured method factor.
- Make sure the CLF is connected to all observed items, including the items of the SB constructs.
- If this breaks your model, then remove the CLF and proceed with the steps below.
- If it does not break your model, then in the steps below, keep the SB constructs covaried to the other latent factors, and keep the CLF connected with regression lines to all observed factors.
- The steps below assume the CLF will break the model, so some instructions that say to connect the SB to all observed variables should instead be CLF to all observed variables (if the CLF did not break your model).
- Then conduct the CFA with the SB constructs shown to influence ALL indicators of other constructs in the study. Do not correlate the SB constructs with the other constructs of study. If there is more than one SB construct, they follow the same approach and can correlate with each other.
- Retest validity, but be willing to accept lower thresholds.
- If change in AVE is extreme (e.g., >.300) then there is too much shared variance attributable to a response variable. This means that variable is compromised and any subsequent analysis with it may be biased.
- If the majority of factors have extreme changes to their AVE, you might consider rethinking your data collection instrument and how to reduce specific response biases.
- If the validities are still sufficient, then conduct the zero-constrained test. This test determines whether the response bias is any different from zero.
- To do this, constrain all paths from the SB constructs to all indicators (but do not constrain their own) to zero. Then conduct a chi-square difference test between the constrained and unconstrained models.
- If the null hypothesis cannot be rejected (i.e., the constrained and unconstrained models are the same or "invariant"), you have demonstrated that you were unable to detect any specific response bias affecting your model. You can move on to causal modeling, but make sure to retain the SB construct(s) to include as control in the causal model. See the bottom of this subsection for how to do this.
- If you changed your model while testing for specific bias, you should retest validities and model fit with this final (unconstrained) measurement model, as it may have changed.
- If the zero-constrained chi-square difference test resulted in a significant result (i.e., reject null, i.e., response bias is not zero), then you should run an equal-constrained test. This test determines whether the response bias is evenly distributed across factors.
- To do this, constrain all paths from the SB construct to all indicators (not including their own) to be equal. There are multiple ways to do this. One easy way is simply to name them all the same thing (e.g., "aaa").
- If the chi-square difference test between the constrained (to be equal) and unconstrained models indicates invariance (i.e., fail to reject null - that they are equal), then the bias is equally distributed. Make note of this in your report. e.g., "A test of equal specific bias demonstrated evenly distributed bias."
- Move on to causal modeling with the SB constructs retained (keep them).
- If the chi-square test is significant (i.e., unevenly distributed bias), which is more common, you should still retain the SB construct for subsequent causal analyses. Make note of this in your report. e.g., "A test of equal specific bias demonstrated unevenly distributed bias."
- What to do if you have to retain the specific bias factor
- You can do this either by imputing factor scores while the SB construct is connected to all observed variables (thereby essentially parceling out the shared bias with the SB construct), and then exclude from your causal model the SB construct that was imputed during your measurement model. Or you can disconnect the SB construct from all your observed variables, but covary it with all your latent variables, and then impute factor scores. If taking this latter approach, the SB will not be parceled out, so you will then need to include the factor score for the SB construct in the causal model as a control variable, connected to all other variables. If you also are able to retain the CLF (i.e., it does not break your model), then you keep it while imputing. If you have only connected the CLF to the observed variables (and not the SB construct), then make sure to use the SB construct as a control variable in the causal model.
Measurement Model Invariance
- VIDEO TUTORIAL: Measurement Model Invariance (using Name Parameters tool)
- VIDEO TUTORIAL: Measurement Model Invariance (using MGA Manager)
Before creating composite variables for a path analysis, configural, metric, and scalar invariance should be tested during the CFA to validate that the factor structure and loadings are sufficiently equivalent across groups, otherwise your composite variables will not be very useful (because they are not actually measuring the same underlying latent construct for both groups).
Configural invariance tests whether the factor structure represented in your CFA achieves adequate fit when both groups are tested together and freely (i.e., without any cross-group path constraints). To do this, simply build your measurement model as usual, create two groups in AMOS (e.g., male and female), and then split the data along gender. Next, attend to model fit as usual (here's a reminder: Model Fit). If the resultant model achieves good fit, then you have configural invariance. If you don't pass the configural invariance test, then you may need to look at the modification indices to improve your model fit or to see how to restructure your CFA.
If we pass the test of configural invariance, then we need to test for metric invariance. To test for metric invariance, simply perform a chi-square difference test on the two groups just as you would for a structural model. The evaluation is the same as in the structural model invariance test: if you have a significant p-value for the chi-square difference test, then you have evidence of differences between groups, otherwise, they are invariant and you may proceed to make your composites from this measurement model (but make sure you use the whole dataset when you create composites, instead of using the split dataset). If there is a difference between groups, you'll want to find which factors are different (do this one at a time as demonstrated in the video above). Make sure you place the factor constraint of 1 on the factor variance, rather than on the indicator paths (as shown in the video).
If we pass metric invariance, we need to then assess scalar invariance. This can be done as shown in the video above. Essentially you need to assess whether intercepts and structural covariances are equivalent across groups. This is done the same as with metric invariance, but with the test being done on intercepts and structural covariances instead of measurement weights. Keep constraints the same, but for each factor, for one of the groups, make the variance constraint = 1. This can be done in the Manage Models section of AMOS.
Contingency Plans
If you do not achieve invariant models, here are some appropriate approaches in the order I would attempt them.
- 1. Modification indices: Fit the model for each group using the unconstrained measurement model. You can toggle between groups when looking at modification indices. So, for example, for males, there might be a high MI for the covariance between e1 and e2, but for females this might not be the case. Go ahead and address those covariances appropriately for both groups. When deleting an item, it does it for both groups. If fitting the model this way does not solve your invariance issues, then you will need to look at differences in regression weights.
- 2. Regression weights: You need to figure out which item or items are causing the trouble (i.e., which ones do not measure the same across groups). The cause of the lack of invariance is most likely due to one of two things: the strength of the loading for one or more items differs significantly across groups, or, an item or two load better on a factor other than their own for one or more groups. To address the first issue, just look at the standardized regression weights for each group to see if there are any major differences (just eyeball it). If you find a regression weight that is exceptionally different (for example, item2 on Factor 3 has a loading of 0.34 for males and 0.88 for females), then you may need to remove that item if possible. Retest and see if invariance issues are solved. If not, try addressing the second issue (explained next).
- 3. Standardized Residual Covariances: To address the second issue, you need to analyze the standardized residual covariances (check the residual moments box in the output tab). I talk about this a little bit in my video called "Model fit during a Confirmatory Factor Analysis (CFA) in AMOS" around the 8:35 mark. This matrix can also be toggled between groups. Here is a small example for CSRs and BCRs. We observe that for the BCR group rd3 and q5 have high standardized residual covariances with sw1. So, we could remove sw1 and see if that fixes things, but SW only has three items right now, so another option is to remove rd3 or q5 and see if that fixes things, and if not, then return to this matrix after rerunning things, and see if there are any other issues. Remove items sparingly, and only one at a time, trying your best to leave at least three items with each factor, although two items will also sometimes work if necessary (two just becomes unstable). If you still have issues, then your groups are exceptionally different… This may be due to small sample size for one of the groups. If such is the case, then you may have to list that as a limitation and just move on.
2nd Order Factors
- VIDEO TUTORIAL: Handling 2nd Order Factors
Handling 2nd order factors in AMOS is not difficult, but it is tricky. And, if you don't get it right, it won't run. The pictures below offer a simple example of how you would model a 2nd order factor in a measurement model and in a structural model. The YouTube video tutorial above demonstrates how to handle 2nd order factors, and explains how to report them.
Common CFA Problems
1. CFA that reaches iteration limit.
- Here is a video: *VIDEO TUTORIAL: Iteration limit reached in AMOS
2. CFA that shows CMB = 0 (sometimes happens when paths from CLF are constrained to be equal)
- The best approach to CMB is just to not constrain them to be equal. Instead, it is best to do a chi-square difference test between the unconstrained model (with CLF and marker if available) and the same model but with all paths from the CLF constrained to zero. This tells us whether the common variance is different from zero.
3. CFA with negative error variances
- This shouldn't happen if all data screening and EFA worked out well, but it still happens… In such cases, it is permitted to constrain the error variance to a small positive number (e.g., 0.001)
4. CFA with negative error covariances (sometimes shows up as "not positive definite")
- In such cases, there is usually a measurement issue deeper down (like skewness or kurtosis, or too much missing data, or a variable that is nominal). If it cannot be fixed by addressing these deeper down issues, then you might be able to correct it by moving the latent variable path constraint (usually 1) to another path. Usually this issue accompanies the negative error variance, so we can usually fix it by fixing the negative error variance first.
5. CFA with Heywood cases
- This often happens when we have only two items for a latent variable, and one of them is very dominant. First try moving the latent variable path constraint to a different path. If this doesn't work then, move the path constraint up to the latent variable variance constraint AND constrain the paths to be equal (by naming them both the same thing, like "aaa").
- VIDEO TUTORIAL: AMOS Heywood Case
6. CFA with discriminant validity issues
- This shouldn't happen if the EFA solution was satisfactory. However, it still happens sometimes when two latent factors are strongly correlated. This strong correlation is a sign of overlapping traits. For example, confidence and self-efficacy. These two traits are too similar. Either one could be dropped, or you could create a 2nd order factor out of them:
- VIDEO TUTORIAL: Handling 2nd Order Factors
7. CFA with "missing constraint" error
- Sometimes the CFA will say you need to impose 1 additional constraint (sometimes it says more than this). This is usually caused by drawing the model incorrectly. Check to see if all latent variables have a single path constrained to 1 (or the latent variable variance constrained to 1).


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To be published in J. Phys. G - Proceedings of SQM 2004 : We review the results from the various hydrodynamical and transport models on the collective flow observables from AGS to RHIC energies. A critical discussion of the present status of the CERN experiments on hadron collective flow is given. We emphasize the importance of the flow excitation function from 1 to 50 A.GeV: here the hydrodynamic model has predicted the collapse of the v2-flow ~ 10 A.GeV; at 40 A.GeV it has been recently observed by the NA49 collaboration. Since hadronic rescattering models predict much larger flow than observed at this energy we interpret this observation as evidence for a first order phase transition at high baryon density r b. Moreover, the connection of the elliptic flow v2 to jet suppression is examined. It is proven experimentally that the collective flow is not faked by minijet fragmentation. Additionally, detailed transport studies show that the away-side jet suppression can only partially (< 50%) be due to hadronic rescattering. Furthermore, the change in sign of v1, v2 closer to beam rapidity is related to the occurence of a high density first order phase transition in the RHIC data at 62.5, 130 and 200 A.GeV.


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Elderly people who have both mild cognitive impairment and a history of serious concussion showed higher amounts of the protein deposits associated with Alzheimer's disease, according to a new study.
The results, published Thursday in the journal Neurology, suggest a potential link between a history of head trauma and later cognitive decline.
Researchers at the Mayo Clinic in Rochester, Minn., enlisted 589 elderly residents of surrounding Olmsted County, beginning in 2004, and administered a battery of cognitive and memory tests, along with brain scans that reveal both structure and metabolic function.
Tests showed 448 of the subjects, aged 70 to 89, had no memory or cognitive problems, while 141 had mild cognitive impairment. A roughly equal proportion of each group reported at least one concussion that involved memory loss, unconsciousness or medical attention. The median age for that concussion event was 21 for men and 32 for women.
Only the brains of those with cognitive impairment showed higher levels of amyloids, a kind of fibrous protein, according to the study.
Researchers suggested that higher amyloid levels within the cognitively impaired group could be a response to a higher level of damage to the myelin coating of the axons of neurons – the brain's white matter.
Amyloid buildup has been associated with neurological disorders, particularly Alzheimer's disease. But studies linking head trauma to Alzheimer's have shown somewhat conflicting results.
Although head trauma correlated with higher amyloid levels among those with mild cognitive decline, it did not correlate with a measurable difference in the volume of their hippocampus, a brain region related to memory, or with lower brain tissue metabolism, the study found.
Could higher amyloid buildup have led to the mild cognitive impairment, then? If so, researchers would expect to see a difference in test scores between those with concussion and those without a head trauma history. No such differences emerged within either the normal or impaired group. (In the cognitively normal group, in fact, those with a concussion history scored slightly higher than those without.)
Results also appeared to rule out differences related to time lapsed from the reported concussion – subjects experienced their concussions around the same age.
Read more: LA Times