My textbook has a feature in every chapter: Dirty Data Alerts. It warns students about ways that data can be manipulated without straight-up lying. I have one Dirty Data Alert dedicated to manipulated  y- axes . Like, truncated y -axes. Because that is the way you manipulate a y -axis, right? RIGHT?! Oh, no, there is a new way to manipulate them without lying. Check out this example, pointed out by @SarahStarberry. Here, the y-axis measures the version number. That's all. Not how good the tool is, or how often it is being used. Just the version number. Like...just wait until I come out with JessChattyTalkTalkBot 8.0 and I destroy all existing competition. If this idea was helpful, you'll probably enjoy my textbook, Psychological Statistics for Everyone . It's basically this blog, but organized into a semester.

This example illustrates how better assessment has likely increased in autism diagnoses (as opposed to the increase being due to vaccines or hysterical parents). It does a good job of illustrating truncated y-axes and the surveillance effect. It also reminds our psychology majors that we have many professional allies and colleagues outside of psychology. Like speech language pathologists.  I found these examples (see below) on Facebook from speech-language pathologist/excellent science communicator  Mrs. Speechie P.   AKA Andi Putt. How to use in class: 1. Truncated y-axis I like how she mentions that truncated y axes can be a scare tactic. I also like that she shows there are still relatively few in the total population. https://www.facebook.com/photo/?fbid=1327073175898079&set=a.463959318876140 On this theme, she shared a second image that does a really good job of showing how proper diagnosis isn't the same thing as fake/inflated diagnoses (a common argument in ant...

Why did I find this after my textbook was published? Damn it. I have a whole section about how Y-axis manipulation can make small differences look huge and then...I find this. Damn it. Source:   https://www.reddit.com/r/dataisugly/comments/1hjr01o/height_of_female_popstars/