I wandered about regression to the mean but with the SSC data being so large there isn’t much room for a big effect—even moving 4SD on the SSC data won’t move the mean much.
I’m afraid I don’t know how to do the maths beyond comparing confidence intervals as I did in the text.
You’re right, I should have double-checked the standard deviations before suggesting regression to the mean. I agree that regression doesn’t plausibly explain the data.
I wandered about regression to the mean but with the SSC data being so large there isn’t much room for a big effect—even moving 4SD on the SSC data won’t move the mean much. I’m afraid I don’t know how to do the maths beyond comparing confidence intervals as I did in the text.
You’re right, I should have double-checked the standard deviations before suggesting regression to the mean. I agree that regression doesn’t plausibly explain the data.