alt Hacker NewsThis article does not make its case. He shows a graph of "random" data, and then just kind of keeps going. But that random data is the meat of the whole thing.
Cut out 60% of the useless text, and focus on explaining why random data should look like that.
Agreed. Also it seems like, if the actual test scores and perceived test scores were both sampled iid, the “perceived” line should just be flat, with everyone being at 50th percentile. The fact that the displayed graph deviates from 50 in a way that more resembles the empirical data makes it seem like a cherry-picked random sample