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I found details of the measurements for the Human Development Index data set at https://hdr.undp.org/system/files/documents/hditraining.pdf. This is a slightly differend UR from the one in the CODAP document.
I certainly like your colors better! And apparently attaching the .codap file as an attachment isn’t a good idea on the forum—noted.
I really want to edit my response, but I guess I’m in the content approval bin. It doesn’t show up for me.
I think we were on the same track. I gave this more work today before seeing your answer, and have it here:
Essentially, I used two samplers: one to generate random draws of two pens, and another to select the genders (without replacement, so I got one boy and one girl in random order). This felt like the natural way to gether samples. (I didn’t know that I could use
count(output, output=filter)like you did—neato.)I then made a new column in the samples table to count how many broken pens there were in each sample. And I got stuck there.
Do you think there’s a way to proceed with my setup? I tried using a histogram to only select those where there was only one broken pen, but I saw no way to check if the pen was assigned to a girl. I made a 2×2 graph showing boy/girl and broken/not broken with only the (broken count==1) points, but if I added more rows to the table, I had to manually go back and re-select only the (broken count==1) rows again. Plus, the 2×2 graph shows double information.
Sorry for the long response, Dan. I’m not getting email updates to responses from this thread, so I missed your request.
Have a look at <span style=”caret-color: #000000; color: #000000; font-family: Montserrat, sans-serif; font-size: 12px; white-space: pre; background-color: #eeeeee;”>https://codap.concord.org/app/static/dg/en/cert/index.html#shared=https%3A%2F%2Fcfm-shared.concord.org%2Fes4CRiXp2DySgO4nc8T4%2Ffile.json</span>
Just to drop in an opinion here in late 2025, but this is an ideal use case for AI. I had a summary table in my PDF of Workshop Statistics 3e (Rossman & Chance). I imply snapped a screen grab of the table and told Chat GPT to make the raw data representing it. I had to answer a couple of formatting questions, but the flat CSV file it produced worked flawlessly.
I really like the ability to add visual confidence intervals to a regression line. Of course, these are confidence bands on the slope, and are essentially showing the lines that would be plotted if the slope ranged over its entire 95% confidence interval.
There are also confidence bands for the individual points. It also is a hyperbola like the one CODAP shows for the slope, but it’s wider. It would illustrate the confidence interval for individual predictions.
This is *fantastic* Dan. I’m so new to CODAP that I haven’t really explored all the plugins yet, so using the Sampler is fantastic.
In fact, I’d say it’s *better*. I don’t really care that students get into the nitty-gritty details of counting cases, just that they get the point that we can generate a sampling distribution from the data itself without resorting to the recipes they learn for parametric tests.
I used to do this kind of thing in JMP, but it required scripting back in my day. And, of course, a rank() function!
The test is equivalent to a Mann-Whitney, but my question is more about finding rankings and computing the distribution of ranks. The PDF explains why there are 35 arrangements for this small data set, which give a probability distribution for the test statistic. I doubt there’s a way to produce the exact probability distribution, but *maybe* there’s a way to generate ranks and use the scrambler to make one.
I mean, I know this is pushing the limits.
Sure thing! Here’s the CODAP shared link:
<span style=”caret-color: #1a202c; color: #1a202c; font-family: Roboto, sans-serif; font-size: medium; white-space: pre;”>https://codap3.concord.org/beta#shared=https%3A%2F%2Fcfm-shared.concord.org%2FtrUDBOSELzjrtQohaW2I%2Ffile.json</span>
And a link to the PDF: