tag:blogger.com,1999:blog-6534665086749553287.post3589891365359303650..comments2024-03-28T11:57:21.902-04:00Comments on CURMUDGUCATION: New Merit Pay Study Hits The Wrong TargetPeter Greenehttp://www.blogger.com/profile/16511193640285760299noreply@blogger.comBlogger1125tag:blogger.com,1999:blog-6534665086749553287.post-48544291006340592572017-04-13T13:54:48.544-04:002017-04-13T13:54:48.544-04:00The effect size for US schools is 0.035 standard d...The effect size for US schools is 0.035 standard deviations. This is equivalent to moving from the 50th percentile to 51.4.<br /><br />2) Not only is converting to "days of learning" absurd - it is theoretically invalid. It's a big discussion and I'll blog on it when I can, but for now:<br /><br />The study the authors use to justify the translation -- Hill, Bloom, et al. (2008) -- specifically points out the "gain" from grade to grade is much larger in the earlier grades than in the later ones when expressed as standard deviations. Moving from K to Grade 1 in reading is 1.52 SD; from Grade 7 to 8, however, is 0.26 SD.<br /><br />This means that "3 weeks of learning" has a completely different meaning when in K than in Grade 7. So you can't just average this stuff and then plop it into your meta-analysis' conclusions.<br /><br />Worse, the tests in Hill et al. are vertically scaled, a minimal requirement when attempting to describe "gains" on a time scale. There is no indication this is true in the merit pay meta-study; I can nearly guarantee the tests used weren't all vertically scaled.<br /><br />The point is the effect of merit pay found here isn't "moderate" -- it's very small. <br /><br />See: https://www.mdrc.org/sites/default/files/full_84.pdf <br /><br />Best,<br />Mark Weber (Jersey Jazzman)Dukehttps://www.blogger.com/profile/16535645107179796099noreply@blogger.com