“Most of the research studies have come from the more developed countries so some care is needed when translating beyond this. It seems one rule of thumb is that the findings may be more generalised when the within school variance is much larger than the between-school variance – and in some parts of the world the between is much larger – and hence the school factors would become more important. For example, the variance between schools, based on the 2009 PISA results for reading across all Organization for Economic Cooperation and Development (OECD) countries, is 36 percent, and variance within schools is 64 percent. For Australia, it is 18 and 72 percent; Canada, 20 and 80 percent; Finland, 8 and 92 percent; New Zealand, 16 and 84 percent; the UK, 24 and 76 percent; Sweden, 9 and 91 percent; and the USA, 30 and 70 percent” (John Hattie, personal communication, July 24, 2016).
Articles in this section
- Why does the Visible Learning research use effect sizes?
- Why do you use an effect size of d=0.40 as a cut-off point and basically ignore effect sizes lower than 0.40?
- What is the preferred timescale over which an effect size can be calculated?
- Is there a bias when using effect sizes in favor of lower achieving students?
- What caution should I take when calculating an effect size?
- Why are effect sizes used when conducting meta-analysis?
- Why can an effect size of 0.40 be gained in a shorter timeframe?
- Can effect sizes be added (or averaged)?
- How accurate are the conclusions drawn from meta-analysis?
- How can the variability associated with each influence be evaluated?