Class-Size Effects in School Systems Around the World: Evidence from Between-Grade Variation in TIMSS

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IZA Seminar

Place: Schaumburg-Lippe-Str. 9, 53113 Bonn

Date: 04.02.2003, 12:15 - 13:30


Presentation by 

Ludger Woessmann (Ifo Institute for Economic Research)


We estimate the effect of class size on student performance in 18 countries, combining school fixed effects and instrumental variables to identify random class-size variation between two adjacent grades within individual schools. Conventional estimates of class-size effects are shown to be severely biased by the non-random placement of students between and within schools. While we find sizable beneficial effects of smaller classes in Greece and Iceland, we reject the possibility of even small effects in 6 countries and of large beneficial effects in an additional 5 countries. Noteworthy class-size effects are observed only in countries with relatively low teacher salaries.

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