Teachers' Collective Efficacy and Teacher Expectations
|Above copied from Hattie's Visible Learning|
Even with the above limited interpretation of Hattie's work, Neil Brown at King's College, London criticizes Hattie's core approach,
"For example, on page 243, Hattie compares the average effect sizes for the “teacher as activator” techniques he has analysed against those for “teacher as facilitator”. On the basis that the former are higher, he concludes “These results show that active and guided instruction is much more effective than unguided, facilitative instruction”. He’s not necessarily wrong, but if we cannot trust the average effect sizes he gives as evidence, and cannot sensibly compare them, we cannot make that conclusion from this data. In which case, the book is not much use as an argument or a useful summary of the data, just as an impressive catalogue of the original meta-analyses."Hattie's updated list comes as an effort to apply his Visible Learning study to higher education.
With this extension, Brown's criticism of Hattie's work ought to be taken seriously. Brown basically points out a major error that Hattie makes in his meta-analysis. Meta-analysis, as Brown points out, is a summary of research studies that share so many things in common. This is important, otherwise, both averaging and comparison are inappropriate. For this reason, Hattie's compilation is only useful with specific factors or interventions. In these cases, the summary and averaging may be appropriate since the studies on one specific intervention may indeed be comparable.
Neither "Teachers' collective efficacy" nor "Teacher expectations" are interventions. Teachers gain confidence often from previous accomplishments. Teacher expectations are often grounded on experience. Both therefore can correlate with student learning and achievement, but this is not a cause-effect relationship. "Yes we can", after all, is a state of mind, a condition, which cannot be imposed on anyone. It is not an intervention that one can easily take and apply.