A professor who uses JMP in a few courses was having problem creating a treemap the way she wanted.
Below is an email of her inquiry and then my response, which included what I think would be a needed enhancement to the controls. .jmp file attached.
Essentially, I'm thinking a new feature would be to have controls on the left for each group variable. Then one could choose 'mean' and 'mean' for both Region and State (as the professor is wanting), or 'sum' for Region and 'mean' for State (as it's doing), or any other desired combo of summary statistics one wants (e.g., min, max, median, ….)
~Kevin
From: Kevin Potcner <Kevin.Potcner@jmp.com>
Date: Tuesday, September 30, 2025 at 10:11 AM
To: Lee-Post, Anita <Anita.Lee-Post@uky.edu>
Subject: Re: treemap question
I see what’s going on, but understand it's not what you're expecting.
I added a stack bar graph to the file to illustrate. There you’ll see that the 'sum of all the avg values' for the States results in the West being higher. That's what the treemap is showing (i.e., the 'mean' for the States, and 'sum of the means' for Region. I understand that you’re choosing 'mean' for the summary statistic not 'sum' and thus expecting the 'mean' to be the summary statistic for both State and Region.
I’m going to forward this email on to tech support to see if it’s some kind of setting that we’re both missing. If not, then yes, I forward this on to product development team as a "new feature idea" as I agree that having more control here would be better.
~Kevin
Kevin Potcner
JMP Academic Programs
kevin.potcner@jmp.com
415.412.5319
From: Lee-Post, Anita <Anita.Lee-Post@uky.edu>
Date: Tuesday, September 30, 2025 at 4:46 AM
To: Kevin Potcner <kevin.potcner@jmp.com>
Subject: treemap question
EXTERNAL
Hi Kevin:
I was under the impression that the size of the rectangle in the treemap is proportion to its value. However, this is not the case in the attached jmp file. The dataset is very simple - a row represents one of the 50 states' region, income, house value, foreign born, ... etc. I created a treemap showing State nested within Region on the x-axis and average House Value on the y-axis:
The treemap showed the West has the largest size of the rectangle - indicating that the West has the highest average House Value? But that's not true because the average House Value in Northeast is the highest:
Please help.
Thanks, Anita
