This page contains references that may interest you if you wish to
explore an issue further. None of these are required.
Perspectives on statistical power:
- Cousens, R. and Marshall, C. 1987. Dangers in testing
statistical hypotheses. Annals of Applied Biology 111:469-476.
Review of type I and type II errors and why 'no evidence of a
difference' is not the same as no difference.
- Knapp, T.R. 1996. The overemphasis on power analysis. Nursing
Commentary on how power analysis can be misused. Some is specific
to nursing and NIH grants; most applies to any experiment.
- Thomas, L. 1997. Retrospective power analysis. Conservation
Good introduction to power analysis.
I have focused on using power to design a new
experiment (i.e. a prospective analysis). Some folks like to use
power to interpret already
collected data. This has some problems, which are nicely reviewed