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what I want to do in this video is think about all of the different ways that we can represent data so right over here we have a list of and I'm just using this as one form of data a list of students scores on say the last test so Amy got 90 percent right bill got 95 percent right cam got 100 percent right I forgot I also got a hundred percent right and Farrah got 80 percent right this is one way to show data remember data is just recorded information and it could be numeric like this it could be quantitative so you're recording actual numbers or it could even be things you could record data on how did they like the test and they could've scored it based on I really liked it I kind of liked it I didn't like it or they might have read it on a scale of zero to five which would have been numbers but it's numbers that are measuring people's opinions as opposed to here we have numbers that are measuring their actual scores so there's all different types of data and I don't want to get into all of that but let's just start thinking about different ways to represent this data so this is one way you could view this as a table where you have the name let me and then you have the score so you have your name column and then you have your score column and I could construct it as a table so it clearly looks like a table like that that's one way one very common way of representing of representing data and just like that that's actually how most traditional databases record data in the tables like this but you could also do it in other ways so you could record it as a as a oftentimes called a bar graph or sometimes a histogram so you could put score on the vertical axis here and then you could have your names over here and let's see the scores let's see maybe male make this a fifty actually let me just mark them off so this is 10 20 30 knots too big 10 20 30 40 50 60 70 80 90 so that's and then 100 so that's 100 two three four five that would be 50 right over there and then you could go person by person so Amy Amy record got a 90 on the exam so the bar will go up to 90 so that is Amy and then you have Bill got a 95 so it's going to be between 90 and 100 so it's going to be right over there Bill got a 95 and so it look like this bill so that is Bill and then you have cam who got 100 on the exam so make sure see I'm hand drawing it so it's not as it's not as precise as if I were to do it on a computer so this right over there that is cams score effort got the same score as cam so her score is going to be let me do that in the color and f4 his color that's F first score right now there she also got 100 so ephra ephra and then finally Farah got an 80 so 60 70 80 so Farah got got an 80 so this is Farah score right over here so this is another way of representing the data and here we see it in visual form but it has the same information you can look up someone's name and then figure out their score ami scored a 90 billion also scored 100 Farah scored and 80 there's even other ways you can have some of this information in fact sometimes you might not even know their names and so then it would have be less information but it might be a list of scores the professor might say hey here are the five scores that were that people got on the exam and they would list 90 95 95 100 100 100 and 80 now if it was listed and if this was all of the data you got this would be less information than the data that's in this bar graph or this histogram and or the data that's given in this table right over here because here not only do we know the scores but we know who got what score here we only know the list of scores but there's even other ways and I this is this is and this is not an exhaustive video of all of the different ways you can represent data you could also represent data by looking at the frequency of scores so the frequency of scores right over here so instead of writing the people you could write the scores so let's see you could say this is 80 85 90 95 and 100 and then you could record the frequency that people got these scores so how many times do have a score of an 80 well forgot it was the only person with the score of 80 so you put one data point there no one got an 85 one person got a 90 so you put a data point there one person got a 95 so you could put that data point right over there and then two people got 100 so this is one and two let's see the other hundred is in this color so I'm stood in the car you wouldn't necessarily have to color code it like this so this is another way to represent and this is you know this access you could just view this is the number so this tells you how many 80s there were how many 90s there are how many 95s and how many hundreds so this right over here has the same data as this list of numbers it's just another way of looking at it and once you have your data arranged in any of these ways we can start to ask interesting questions we can ask ourselves things like well what is the range of data what is the range in the data and the range is just the spread between the lowest point and the highest point so the range in this data it's going to be the difference between the highest score and the highest score is our 100 and the lowest score and 80 so the range is going to be the difference between the max minus the min the maximum score minus the minimum score so it's going to be 100 minus 80 is equal to 20 so that gives you a sense of things it kind of gives you a sense of spread you could also ask yourself well how many how many people scored below these are just interesting questions below 100 and you can actually answer that question well actually you could have answered either of these questions with any of these different ways of looking at the data if you say how many people scored below 100 well 1 2 3 how many people scored below 100 1200 is up here so it's going to be 1 2 3 how many people scored below 100 1 2 3 how many people scored below 100 1 2 3 and so any way you look at it you would have gotten 3 and you could also ask yourself what is the most frequent score so most frequent most frequent and once again you could answer that question with any of these ways of representing this data you could look at our original table and you say look there's only 190 195 180 there's 200s so you'd say look there's the most frequent scores 100 you'd see that over here - you actually have 200s there's only one of each of the other scores here you also see the 200s and here is probably the clearest if you're looking at frequency sometimes this might be called a frequency plot and sometimes it's called oh well sometimes the official it's often called a frequency plot and you see here the most frequent one is the one that has the most dots on it which is 100 so anyway that's just a very high-level overview of how you can look at data and different ways to represent data but the one thing I really want you to get from this is that these are all different ways of representing the same data and we could probably invent other ways of doing it as well