Wednesday, July 28, 2010

Do Kindergarten Teachers Matter More than Parents?

New research on the value of kindergarten teachers is remarkable

In fact, it seems a bit hard to believe. If kindergarten teachers matter as much as this new research suggests, then you would think that parents would have a large influence on their kids' adult outcomes. After all, you spend a lot more time with your parents than in your kindergarten class. But much research in behavioral genetics finds very little evidence for significant parental effects. (See Judith Harris's The Nurture Assumption.) So I am puzzled.

Update: Judith Harris emails me:
I guess it's been a while since you read my book. In Chapter 11 of The Nurture Assumption I described the case of a gifted first-grade teacher, "Miss A," who had a long-lasting beneficial effect on her students, and I proposed an explanation of how and why this happened.
Yes, it has been a while, and since I am now at the Jersey shore, I don't have a copy handy. I much appreciate the correction.

Update 2: From Raj Chetty, one of the authors of the study:
I'm writing in reference to your interesting comment about our Kindergarten paper. I think our results are actually consistent with your perfectly sensible intuition that parents should matter more than teachers, for two reasons:

(1) the Kindergarten class effects are large in aggregate but explain a small share of the variance in earnings (less than 5%) overall. A better class leads to higher average earnings (3% higher earnings for a 1 SD improvement in teacher quality), but there is a lot of variation around the mean.

(2) The best evidence I've seen on the long term impacts of parents is this quasi-experimental paper by Bruce Sacerdote published in the QJE. It shows that parental characteristics explain about three times more of the variation in adult outcomes than KG classes, consistent with your intuition.