Clay Reisler e-mails in a real tearjerker this morning. His class noticed that the meteorologist on the local Fox affiliate was charting the weather with unspecified intervals and axes, basically blaspheming the data representation gods.
So they e-mailed Fox and asked for a clean set of graphs to analyze (ie. no meteorologist cluttering up the frame) and Fox obliged! Then the students’ assignment was to compile a list of recommendations and e-mail them back to Fox. End of story, right? Yeah, except Fox took their recommendations to heart!
I hope you’ll head over to room 2001 and show those kids some love for speaking math to power.
JoeFebruary 16, 2011 - 9:18 am -
Can we see the improved chart(s) and/or their recommendations?
If the top image is the before, and the bottom is the after, what was the improvement or change?
Dan MeyerFebruary 16, 2011 - 9:26 am -
Yeah, like the kids admit in the blog post, they’d rather have accurate scales and axes, but it’s a win, nevertheless, that Fox removed the misleading y-axis and the ambiguous intervals.
Jameson BrownFebruary 16, 2011 - 10:06 am -
I don’t get it. Just what exactly is wrong with the graphs?
MichaelFebruary 16, 2011 - 10:47 am -
The issue the students had was that there were horizontal grid lines in the first picture but no scale anywhere. Starting at the bottom, it could be interpreted each line is about 10 degrees, but looking at the next plot, it goes up 3 lines or about 30 degrees not the 23 as listed. It is EXTREMELY tough to figure out what the scale of the y-axis (i.e. horizontal lines) is to help determine what the temperature was between days.
In the second graph, eliminating the horizontal lines helps to eliminate this confusion.
Though, I agree with the students, there should be a y-axis with a clearly defined scale.
BreedeenFebruary 16, 2011 - 12:08 pm -
Jameson: One glaring error is that 33 degrees and 36 degrees are apparently on the same line of the grid.
MathyCathyFebruary 26, 2011 - 6:53 am -
Well done! And thanks for sharing – we are working on misleading graphs in grades 6 and 7 currently, and the first graph will be a great “What’s Wrong With This?” to start a lesson.