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In this chapter results of a research synthesis and quantitative meta-analyses of three facets of time effects in education are presented, namely time at school during regular lesson hours, homework, and extended learning time. The number of studies for these three facets of time that could be used for a qualitative synthesis (so-called vote counting on the basis of significant and non-significant associations) was 31 for learning time at school, 52 for homework, and 15 for out of school learning. Effect sizes were available for 16 studies on learning time at school and 45 studies concerning the effects of homework. The number of studies on out of school learning was too small to conduct a quantitative meta-analysis. The average effect size for the meta-analyses on time at school and homework were .05 (Fisher Z coefficient) for both time facets. These results are considerably lower than those that could be obtained by averaging results of other meta-analyses; as these averages amounted to .18 for time at school, and .15 for homework.
Original languageEnglish
Title of host publicationEffectiveness of time investments in education
EditorsJ Scheerens
Place of PublicationCham
Number of pages88
ISBN (Print)978-3-319-00923-0
Publication statusPublished - 2014

Publication series

NameSpringerBriefs in Education


  • IR-87293
  • METIS-297879

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    Hendriks, M. A., Luyten, J. W., Scheerens, J., & Sleegers, P. J. C. (2014). Meta-analyses. In J. Scheerens (Ed.), Effectiveness of time investments in education (pp. 55-142). (SpringerBriefs in Education). Cham: Springer.