I found this post :   However, they did not explain clearly in terms of mathematical model. Could anyone make it more clearly please ?
There exist several implementations of the GBDT family of model such as:   GBM XGBoost LightGBM Catboost.    What are the mathematical differences between these different implementations?  Catboost seems to outperform the other implementations even by using only its default parameters according to , but it is still very slow.  My guess is that catboost doesn't use the dummified variables, so the weight given to each (categorical) variable is more balanced compared to the other implementations, so the high-cardinality variables don't have more weight than the others. It allows the weak categorical (with low cardinality) to enter to some trees, hence better performance. Other than that, I have no further explanation.
Can you cast a spell learned from the Magic Initiate feat using spell slots? Can you cast a spell learned from the Magic Initiate feat using spell slots? Say I play a wizard who learns cure wounds by taking the Magic Initiate feat. Could I cast that spell using the Wizard's spell slots? Let $f$ and $g$ be entire functions such that $f^n+g^n=1$, where $n\geq 3$ is an integer. Prove that $f$ and $g$ are constant.  I suppose I should somehow prove that either $f$ or $g$ is bounded so that I can apply Liouville's Theorem, but I don't see how. I tried setting the derivative of the left hand side equal to zero and work with that but that did not seem to work. How do TTL NAND gates work? This is supposed to be a simple NAND gate. I understand how the output is 1 if one of the inputs is zero but if both inputs are 1 then the base of Q1 is supposed to be zero. This is what I don't understand. I know that Q2 and Q3 will be in cut off so the base of Q1 is floating. If that is true, how is it zero then?When A and B are open does current flow through Q2  Q3 via R1 to turn on Q1? Filter questions with no accepted answer I have some questions with answers, but none of the answers are acceptable (just wrong).  I'm sure there are a lot more people with the same problem.  Can you add a button to filter questions with answers but no accepted answer?  This way, people will see those questions and maybe try to offer a new perspective. I have a list of Line_item__c which is storing my line items as  List&lt;Line_Item__c&gt; toInsertList = new List&lt;Line_Item__c&gt;();   I am inserting these records in database using the below statement :  List&lt;Database.Saveresult&gt; insertResults=Database.insert(toInsertList, false);   Now the result is stored in insertResults which is of Database.Saveresult type but i want the result in a list of Line_Item__c. How do i do this. If anyone has a idea, it will be of great use. Evaluation of $\lim_{n\rightarrow \infty}\frac{n!\cdot e^n}{\sqrt{n}n^n}$ without stirling approximation Evaluation of $\displaystyle \lim_{n\rightarrow \infty}\frac{n!\cdot e^n}{\sqrt{n}\cdot n^n}$   $\bf{My\; Try::}$we can write it as $$l=\lim_{n\rightarrow \infty}\frac{e^n}{\sqrt{n}}\cdot \left(\frac{1}{n}\cdot \frac{2}{n}\cdot \frac{3}{n}\cdots \cdots \frac{n}{n}\right)$$  $$\ln (l) = \lim_{n\rightarrow \infty}\bigg[n-\frac{1}{2}n+\sum^{n}_{r=1}\ln\left(\frac{r}{n}\right)\bigg]$$  Now how can i solve it, Help required, Thanks If in a UFD every maximal ideal is principal then it is a PID This is something I just realised I don't entirely know the answer to, so I'm going to ask it here as I think it's interesting.  In most non-scientific writing on depth of field, diagrams generally show camera and subjects as being perfectly parallel, e.g.    However, is this a more accurate representation of the focal plane?    Are there ways to optically alter the shape of the focal plane?  Note: Obviously these diagrams are two dimensional, but I'm assuming in the second diagram the shape would be spherical with the sensor at the center. Capturing a time in milliseconds Solving "mv: Argument list too long"? I have a folder with more than a million files that needs sorting, but I can't really do anything because mv outputs this message all the time  -bash: /bin/mv: Argument list too long   I'm using this command to move extension-less files:  mv -- !(*.jpg|*.png|*.bmp) targetdir/ Incorrect whitespaces or list item size in Android SE app Noticed that sometimes when there are 10+ answers to a question - some answers look like they have \n\n...\n line breaks in the end, so the body of the answer has incorrect height.  It probably has something to do with ViewHolder or adapter not setting correct row height. Although as far as I know, it should do this according to text amount/length. Why doesn't Steam start? When I try to start Steam nothing happens. Reinstall doesn't help.  $ steam Running Steam on ubuntu 13.04 64-bit STEAM_RUNTIME is enabled automatically Installing breakpad exception handler for appid(steam)/version(1378500910_client) Installing breakpad exception handler for appid(steam)/version(1378500910_client) Installing breakpad exception handler for appid(steam)/version(1378500910_client) unlinked 0 orphaned pipes removing stale semaphore last operated on by process 7278 with name 0eBlobRegistryMutex_DC7EBB4AEA41D3C6C74E5EFFD6757CEC removing stale semaphore last operated on by process 7278 with name 0eBlobRegistrySignal_DC7EBB4AEA41D3C6C74E5EFFD6757CEC removing stale semaphore last operated on by process 7278 with name 0emSteamEngineInstance removing stale semaphore last operated on by process 7278 with name 0eSteamEngineLock Gtk-Message: Failed to load module "overlay-scrollbar" Installing breakpad exception handler for appid(steam)/version(1378500910_client) [0913/182910:WARNING:proxy_service.cc(958)] PAC support disabled because there is no system implementation   How to fix it? Article "communicated by" What does it mean when it says under a journal article that it has been communicated by "XYZ" where XYZ is not the author but some other scholar with a very strong reputation? What is the relationship to the actual author and/or the content? Is this some sort of seal of approval to get results out and known quickly? (I am specifically wondering in the context of mathematics and mathematical physics.) "Notice: Undefined variable", "Notice: Undefined index", and "Notice: Undefined offset" using PHP When I loaded the review page (in Stack Overflow, though I have no specific reason to think it is related) I got a weird hat in the upper left hand corner.    See the hat in the upper left hand corner?  That's belonging to user # .  His profile page also has the hat in a ... weird ... location, but not this weird.    I'm guessing this is due to the not-loaded image for the avatar (adblock blocks Facebook avatars for me often)?  It also causes the toolbar notification to show his link unless I'm hovering over something else.  It also changes the location of the gray box to the upper left hand corner when I hover over the hat (and hovering over the white box does nothing).  It's definitely him (or any not-loaded avatar perhaps), once he fell off the last 6 reviewers it stopped appearing. , clicking &quot;link&quot; &quot;share&quot; for anwers yields a short (traceable) URL in the &quot;share a link to this answer&quot; dialog, such as †:  These short URLs show no clue about the linked question whatsoever. Also, when different people use a short URL for the very same post, then the user id suffix makes those be different URLs for a browser. Such links will then not be shown as visited‡. I know how to get URLs that have a proper slug. But as I see  pop up on these sites (where referrals ), I assume many others just don't realize full URLs would be better for use on these sites themselves? Or many don't want to do the little effort to get the full URL? So: can we please have an easy way to get the full URL as well, in a way that is easily found for those who don't know about the different links? (Currently for questions, clicking &quot;link&quot; has the same effect. But then one can also right-click the title, or take the URL from the location bar, to get the full human-readable URL. Once, Jeff .)  † The short links for answers are not (yet) [automatically converted][6] into a clickable question title either, unlike links such as `https://meta.stackexchange.com/questions/74274/privacy-leak-in-permalink#75963`, which renders as https://meta.stackexchange.com/questions/74274/privacy-leak-in-permalink#75963 But I guess that will change soon.  ‡ On Meta the CSS for posts doesn't indicate such difference anyway, which is a different issue. I want to know, is there a way to make a tungsten lightbulbs filament withstand a mass amount of thermal shock while still producing a vast amount of heat? How to set up USB for Virtualbox? Find the minimum value of $f(x,y,z)=\frac{x^2}{(x+y)(x+z)}+\frac{y^2}{(y+z)(y+x)}+\frac{z^2}{(z+x)(z+y)}$. Find the minimum value of $f(x,y,z)=\frac{x^2}{(x+y)(x+z)}+\frac{y^2}{(y+z)(y+x)}+\frac{z^2}{(z+x)(z+y)}$ for all notnegative value of $x,y,z$.  I think that minimum value is $\frac{3}{4}$ when $x=y=z$ but I have no prove. How do I install iTunes on Ubuntu?