Teacher effectiveness

Kane, Rockoff and Staiger (2007)

How do teachers compare each year? Figures represent comparison with traditionally certified teachers: e.g. TFA with 1 year of experience is SD better than certified with 1 year of experience

We know from the table before that Teaching fellows, TFA are associated with higher value added than traditionally certified teachers on average (e.g. TFA.02 SD above for math) We also know TF and TFAs are better than certified teachers after their first year This graphs show the gains over the years with respect to each teacher group’s previous year, over and above the the gains of certified teachers: it is confusing

Retention rates

Variation within groups

Would you hire from TFA? Supporters of the TFA program argue that corps members have larger impacts on student achievement than regularly certified teachers, particularly among those certified teachers willing to work in low-income schools. Critics of the program argue that because of high turnover rates, school districts are constantly having to replace TFA corps members with novice teachers For critics to be correct there would have to be: – Large returns to experience beyond three years – Comparatively small differences between TFA and traditionally certified teachers

Are alternative certification programs scalable? Outside cities? Is it a silver bullet: would hiring from any of these programs ensure we have high quality teachers? Is sufficient effort put into retaining teachers? Are we giving up on getting good “professional teachers”?

Chetty et al. I 1M children tracked in NYC VA measures are largely accurate (unbiased) and more so as more year data is available. Look at: – Possible sorting on observables not used to calculate test scores, e.g. family income -> minimal bias – Quasi-experimental design: assess the effect of switching teachers within schools (idyosinchratic?) Sorting of classrooms is on prior test scores (which VA measures control for): – Without prior test scores, bias of VA estimates is of 40% – With prior tests scores is 0%

High VA teachers do have an effect on classroom performance

Chetty et al. II High VA teachers have a causal effect on income later in life 1 years worth of good teaching in 8 th grade has an effect of increasing lifetime earnings by $18,000, so for a class of 20 ~$360,000

Top 5% of teachers have an effect of ~$600 or 3% of earnings, yearly

Firing bottom 5% of teachers

Improved estimates of VA over time

Questions Is the effect through test scores? Is this a large effect? Is it cost-effective? – What would we need to do to hire these kinds of teachers? – How does it compare to other interventions? – Who captures the benefits Is this replacing of teachers feasible on a large scale? Does it have implications for merit pay? Does it change your view on the use of VA measures to evaluate teachers? Should these VA measures be used more widely, e.g. reported to parents?