WASHINGTON — Elementary- and middle-school teachers who help raise their students’ standardized-test scores seem to have a wide-ranging, lasting positive effect on those students’ lives beyond academics, including lower teenage-pregnancy rates and greater college matriculation and adult earnings, according to a new study that tracked 2.5 million students over 20 years.
The paper, by Raj Chetty and John N. Friedman of Harvard and Jonah E. Rockoff of Columbia, all economists, examines a larger number of students over a longer period of time with more in-depth data than many earlier studies, allowing for a deeper look at how much the quality of individual teachers matters over the long term.
[WS:] Two comments.
1. With the n = 2+ million, any difference is significant.
2. An alternative explanation of the findings is plausible - good teachers tend to be attracted to good schools i.e. schools whose students tend to value education and thus benefit from education more than those who do not value it. So the effect of teacher quality on student lives is spurious - both could be caused by the value students place in receiving education.
But as JK Galbraith once commented, economists are in the business of providing needed conclusion to those in a position to pay for them. With few exceptions, I would not give a rat's ass for anything written by an US economist, no matter how they cook their numbers.
Wojtek