This is a very interesting topic and the article seems quite thorough. But I have trouble interpreting the crucial "School and track sorting can bolster or bust academic achievement" plots: The y axis is labelled "Graduation score percentile", but it has negative numbers on the scale. How are these values being corrected?

The series for 1-school towns on the left plot is basically flat; am I supposed to believe that, in such towns, students entering the school with a 0.5 on the high school admission test appear at the same exit exam percentile (implying that they have the same average exit exam scores) as those who entered with a 9.5? That can't possibly be true.

ETA: I also thought the conclusion -- that other countries should adopt a similar education model -- was out of step with most of the body text, which seemed to stress the downsides for weaker students. (There's no actual contradiction here, and perhaps the claim about most of society's advances being due to the top-end achievers was intended to justify this angle, but I was nevertheless surprised that there wasn't much discussion of why this upside should overpower the concerns for weaker students.)

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alephnerd 5 days ago | parent | next [-]

> That can't possibly be true

It tracks with spatial inequality.

A 1 school town is highly likely to be a small rural town with limited economic prospects. Like plenty of CEE countries, the overwhelming majority of opportunities have historically been clustered in the capital and a couple regional cities.

The kind of town or village with only a single school is going to have fewer social benefits or services compared to an urban school.

Basically, what it is saying is students in those kinds of towns are s** out of luck statistically speaking compared to their urban peers.

There's a reason Romania's HDI has remained lower than Russia's until recently thanks to EU funding to help develop Romania (which is now on track to become a major economic pole in the CEE)

Edit: can't reply

> A lot turns on this. (I suppose I could read the underlying paper, but I'm lazy.)

I recommend checking it out. It explains the methodology and some potential wonkiness. It's always good to read the docs

	▲	akoboldfrying 5 days ago \| parent [-]
		I acknowledge that effect is present, but it's simply not strong enough to dominate natural variation in ability (for which high school entrance exam scores are a proxy) to the point where the results are completely flat -- in fact, students who achieved the highest scores on the entrance exam were slightly lower in exit scores on average than those with low or medium entrance scores! What this tells me is that some kind of correction is being applied to those y values (we already know this because of negatives numbers on a "percentile" axis) -- but what? A lot turns on this. (I suppose I could read the underlying paper, but I'm lazy.)

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f33d5173 5 days ago | parent | prev [-]

It says "effect" of school sorting. So the "graduation score percentile" must be the change in percentile due to school sorting.

	▲	akoboldfrying 4 days ago \| parent [-]
		That seems plausible, but change with respect to what baseline? I think the sensible baseline would be the entry exam percentile (x axis), but others are conceivable.