If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

Main content
Current time:0:00Total duration:4:53

Video transcript

thrill soda hired a marketing company to help them promote their brand against yummy Cola the company gathered the following data about consumers preference of soda so they have year by year percentage of respondents who preferred yummy Cola percentage of respondents who performed who prefer thrill Cola and these are people who had no preference in 2006 80 percent liked yummy only 12% liked thrill and 8% didn't like either one or didn't have any preference and so actually just from here you see the many many more people like to yummy Cola than thrill coal actually every year over here so thrilled Cola definitely has something they have an uphill battle but then they said the advertising company created the following two graphs to promote thrill soda and so let's see what's happening over here so and let's think about whether this is misleading or not so if we look at this graph over here in 2006 sure enough 80% liked yummy Cola then 2007 76% then it keeps going than 77% then 73% then 73 to the 68 so this is actually accurate data it actually represents the data that's given that's given right over here I'll do it in the same actually represents this data very faithfully then right over here if we look at this chart percentage of people who prefer thrill soda so over here in 2006 twelve percent preferred thrill soda 2006 12% 2007 19% 2008 19% then we go up to 20 21 and 25 so the graphs are actually accurate they're not lying these are actually the data points of the percentage who prefer thrill soda now what's misleading is if someone were to just look at these two graphs without actually looking at the scales over here they'll see two things they'll say oh look you see a declining trend and that's what blind graphs are good for for seeing trends they say look I see a declining trend in the number of and the percentage of people who prefer yummy Cola and I see this increasing trend in the percentage of people who prefer thrill cold and that's true they have a declining trend here and you have an increasing trend here but what's misleading here is the way that they've plotted the scales these scales are not the same so when you look at this you say not only is there an increasing trend of people who prefer drill soda but it the way they set up the scale that it looks like the trend is above it looks like if you look you're the human brain is tempted to compare these and they say look not only is this an upward trend but it's above this trend right over here even in 2006 this data point looks higher than then these data points right over here but the reality is is that it's only because this scale is distorted and this is the oldest trick in the book when the plotting line graphs is all depends on the scale so this just looks good because they used this scale that went from 0 30 as opposed to 0 100 the more the better thing to do or the more genuine thing to do or the more honest thing to do would have actually been applaud them on the same graph although they did that that wouldn't have painted a very good picture for thrill soda so if we plotted it on the same graph thrill soda let's try that out so in 2006 12 and actually this is even worse you could actually wouldn't even be able to plot thrill soda on this graph because they started this graph right over here at 50% they didn't even start it at 0% so you actually would not even be able to plot thrill soda on this graph if you did you would have to extend this graph all the way down so you would have to extend this graph all the way down to you know so this would have to be 40 this wouldn't be 30 you this would be 20% this would be 10% and then or down all the way over here would be 0% and then the thrill soda graph would will be all the way down here so it was like 12% and it goes all the way up to like 25 percent so the thrill soda so it would have looked something like this the graph would have looked something like this which is nowhere near if you plotted these on the same day on the same scale on the same graph then it would have still been pretty obvious that a lot more people even though the trend is downward a lot more people prefer you prefer yummy Cola to thrill Cola so there's two very disingenuous things going on over here one is the actual scale for this amount of distance on this scale they represent 10% so whatever the gain is it looks like it's a huge gain and over here that same amount they're actually representing a larger amount they're representing closer to 15 or 16 percent and then the main thing is they started the scale here at 50 percent so they're not showing how many people really prefer how how long 80% or even 70% really is and over here they start at zero and they just have a larger scale so it makes it look like out the gate a lot of people prefer or a comparable amount of people prefer thrill and that the trend is up but the reality is still way more people prefer yummy Cola so this was a little bit or actually very very not so honest way of representing the data or I guess you say they're misrepresenting the data