FURTHER INFORMATION
» Executive Summary
» Final AER Papers (with Appendices)
Part 1: Bias in VA Estimates
Part 2: LongTerm Impacts
» NBER WP 17699 [old version]
» Education Next article
» Video of Presentation
» Presentation Slides [PPT] [PDF]
» STATA Code
» Press Coverage
» Discussion of ASA Statement
» Response to Adler (2014)
» Note on Prior Score Placebo Tests
» Response to Rothstein (2014)


A teacher's "valueadded" is defined as the average testscore gain for his or her students, adjusted for differences across classrooms in student characteristics (such as their previous scores). Is teacher valueadded a good measure of teacher quality?



When a high valueadded (top 5%) teacher enters a school, endofschoolyear test scores in the grade he or she teaches rise immediately... 
 ... and students assigned to such high valueadded teachers are more likely to go to college, earn higher incomes, and less likely to be teenage mothers. On average, having such a teacher for one year raises a child's
cumulative lifetime income by $80,000 (equivalent to $14,500 in present
value at age 12
with
a 5% interest rate).

 The earnings gains from replacing a low valueadded (bottom 5%) teacher with one of average quality grow as more data are used to estimate valueadded. Discounting future earnings gains to present value, the gains are $270,000 with 3 years of data. If future earnings are not discounted, cumulative earnings gains surpass $1.4 million per class.


We conclude that great teachers create great value, and that
testscore based valueadded measures are one useful input into
identifying such teachers.



Note: The results of this study were originally disseminated as NBER
Working Paper 17699 in December 2011. The final results of this study
are published in the American Economic Review as two separate papers.
The first paper evaluates bias in VA estimates, while the second
estimates teachers' longterm impacts. The two final papers as well as
the original paper are posted on this site; the STATA code corresponds
to the revised manuscripts.


