And you still don’t, unless you are well read and know what a difference of 2.4 in Z-score means. Are the Z-scores similar to IQ points, in which case 2.4 is not very much, or are they standard deviations, in which case 2.4 is a devastating and horrifying loss? Or something else entirely?
z-scores count standard deviations. So if your fluid intelligence is one standard deviation better than the typical person your age, then when you’re in your 50s you’ll be about as good as a typical person in their 20s.
This is terrific graph. Do you have a source? I had no idea the relationship was so strong.
And you still don’t, unless you are well read and know what a difference of 2.4 in Z-score means. Are the Z-scores similar to IQ points, in which case 2.4 is not very much, or are they standard deviations, in which case 2.4 is a devastating and horrifying loss? Or something else entirely?
z-scores count standard deviations. So if your fluid intelligence is one standard deviation better than the typical person your age, then when you’re in your 50s you’ll be about as good as a typical person in their 20s.
It seems like the horrifying interpretation is correct. (See my other comment where I cite a paper providing more data.)