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Selection bias is the most powerful force in education

fredrikdeboer.com

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Re: Selection bias is the most powerful force in education

#21

I'm from the midwest and most people who weren't aiming for Ivy Leagues just took the ACT.

Yah. It's weird that de Boer argues selection bias is in play in SAT participation between MS (3%) and CT (88%) when 100% of MS high schoolers take the ACT. That seems to be what's happening here: the kids in MS taking the SAT in addition to the ACT are the ones aiming for elite schools.

>the kids in MS taking the SAT in addition to the ACT are the ones aiming for elite schools

Which is an extreme selection bias. The ACT should have been mentioned to provide more context, but the actual argument works without it.

Re: Selection bias is the most powerful force in education

#22
For pure math, by far, essentially the only, "force" in education is being able to work the exercises. That's ugrad school. For more, be able to do new, correct, and significant original research in math. And that's all Folks!

Nothing but nothing, nichts, nil, nada, zip, zilch, zero, not social skills, not presentation of self, not frequency of bathing, not haircut or hair style, not clothes, not politics, not race, not gender, not country of origin matters at all.

Example: For positive integer n and the set of real number R, show that, on any finite intersection of closed half spaces C in R^n, any linear function that is bounded above on C achieves its least upper bound on C.

Example: In a separable metric space, each closed set is the union of a perfect and a set that is at most countable.

Example: Prove that there are no countably infinite sigma algebras.

Example: For positive integer n and the set R of real numbers, for any closed set C in R^n, there exists a function f: R^n --> R so that f(x) = 0 for all x in C, f(x) > 0 otherwise, and f is infinitely differentiable.

Examle: For positive integer n and the set of real numbers R, show that convex f: R^n --> R is continuous.

Example: For triangle ABC, by Euclidean construction, find D on AB and E on BC so that the lengths AD = DE = EC.

Re: Selection bias is the most powerful force in education

#23

I'm from the midwest and most people who weren't aiming for Ivy Leagues just took the ACT.

Yah. It's weird that de Boer argues selection bias is in play in SAT participation between MS (3%) and CT (88%) when 100% of MS high schoolers take the ACT. That seems to be what's happening here: the kids in MS taking the SAT in addition to the ACT are the ones aiming for elite schools.

That's... exactly what he said.

Re: Selection bias is the most powerful force in education

#24
I think the real problem described is that people are judging schools based on the performance of their students. There are other objective factors that won't be as affected by selection bias such as: breadth of extra-curricular options in sports and in the arts. Number of AP classes offered. Teacher to student ratio. Budget per student. Does the school have newer computers, working instruments, modern facilities?

Re: Selection bias is the most powerful force in education

#25

Earlier quoted context omitted.

Yah. It's weird that de Boer argues selection bias is in play in SAT participation between MS (3%) and CT (88%) when 100% of MS high schoolers take the ACT. That seems to be what's happening here: the kids in MS taking the SAT in addition to the ACT are the ones aiming for elite schools.

>the kids in MS taking the SAT in addition to the ACT are the ones aiming for elite schools Which is an extreme selection bias. The ACT should have been mentioned to provide more context, but the actual argument works without it.

You say it better than I do. Agreed it's an extreme selection bias, just want to point out that it's slightly different than the one de Boer seemed to be pointing out.

Re: Selection bias is the most powerful force in education

#26
post #10

Earlier quoted context omitted.

That depends on what you classify as failure. It failed in the sense that the white and wealthy mostly fled to the suburbs and reversed any progress integration had made. It succeeded in the sense that in the places and times where schools were well integrated the racial achievement gap closed.

The racial achievement gap closed? That would be a huge story and I would be surprised if I missed it...unless you mean the gap closed within the school (i.e. not relative to society at large) because the remaining whites achievements were lower than the average before they fled, i.e. selection bias :)

Integrated schools help to reduce racial achievement gaps. In fact, the racial achievement gap in K–12 education closed more rapidly during the peak years of school desegregation in the 1970s and 1980s than it has overall in the decades that followed—when many desegregation policies were dismantled. More recently, black and Latino students had smaller achievement gaps with white students on the 2007 and 2009 NAEP when they were less likely to be stuck in high-poverty school environments. The gap in SAT scores between black and white students continues to be larger in segregated districts, and one study showed that change from complete segregation to complete integration in a district could reduce as much as one quarter of the current SAT score disparity.

https://tcf.org/content/facts/the-benefits-of-socioeconomica...

Not only were they more successful in school, they were more successful in life as well. A 2011 study by the Berkeley public policy professor Rucker C. Johnson concludes that black youths who spent five years in desegregated schools have earned 25 percent more than those who never had that opportunity. Now in their 30s and 40s, they’re also healthier — the equivalent of being seven years younger.

http://www.nytimes.com/2012/05/20/opinion/sunday/integration...

Desegregation and Black Dropout Rates J, Guryan. 2001. has some good data on the decline in black dropout rates in districts with integration.

Re: Selection bias is the most powerful force in education

#27
post #8

Earlier quoted context omitted.

That depends on what you classify as failure. It failed in the sense that the white and wealthy mostly fled to the suburbs and reversed any progress integration had made. It succeeded in the sense that in the places and times where schools were well integrated the racial achievement gap closed.

Do you have any pointers to data showing this close? Most of what I've seen shows the gap being shockingly persistent in the face of intervention across a wide variety of systems, but I'm always looking for more.

I reccomend Malcolm Gladwell's podcast on the subject. He makes a strong argument that the failure to integrate teachers to any degree caused a large part of the failure. Some of his sources are on the page, but I haven't reviewed them well personally.

http://revisionisthistory.com/episodes/13-miss-buchanans-per...

Re: Selection bias is the most powerful force in education

#28
post #10

Earlier quoted context omitted.

The racial achievement gap closed? That would be a huge story and I would be surprised if I missed it...unless you mean the gap closed within the school (i.e. not relative to society at large) because the remaining whites achievements were lower than the average before they fled, i.e. selection bias :)

Integrated schools help to reduce racial achievement gaps. In fact, the racial achievement gap in K–12 education closed more rapidly during the peak years of school desegregation in the 1970s and 1980s than it has overall in the decades that followed—when many desegregation policies were dismantled. More recently, black and Latino students had smaller achievement gaps with white students on the 2007 and 2009 NAEP whe…

Integrated schools help to reduce racial achievement gaps. In fact, the racial achievement gap in K–12 education closed more rapidly during the peak years of school desegregation in the 1970s and 1980s than it has overall in the decades that followed—when many desegregation policies were dismantled.

Why I don't find that evidence convincing: https://news.ycombinator.com/item?id=13904403

Re: Selection bias is the most powerful force in education

#29
post #7

Sending a troubled kid to a great private school probably will cause the kid to do better: because all the other students are doing well the bad students peers are working hard so the bad student sees that example and is likely to succumb to peer pressure and do better. For this to work the troubled kid needs to be kept out of the gangs and whatever else outside of school will lead to bad examples. However selection…

You can almost postulate a sort of "memetic herd-immunity" where if a large enough proportion of the student population is inoculated against bad study habits, a few stragglers will be ok. But if the balance tips too far, the stragglers start joining up and reinforcing each others' bad study habits.

Re: Selection bias is the most powerful force in education

#30

I'm from the midwest and most people who weren't aiming for Ivy Leagues just took the ACT.

I'm from the East Coast and I took both, submitted both on college applications (I actually did slightly better on the ACT, not sure if it helped) but yeah SAT was given priority in school/training programs. I had to seek out the ACT.
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