bob1, on 09 January 2012 - 04:35 PM, said:
In general people are clueless about statistics; I frequently see incorrect use of statistics in published papers and in other media such as in news reports. It is a sad fact that there is very little knowledge of the correct usage of stats, even amongst senior scientists. I wish there was more teaching of the correct usage of stats for non-statisticians (i.e. us poor biologists and other scientists).
With an n=3 you should have used a non-parametric test, and/or looked at your data to see if you can assume a normal distribution of the results. ANOVA is not really useful for samples below about n=30, and the power diminishes rapidly below that. Unfortunately there is not much that you can say about incorrect usage, other than to follow up and make corrections where needed!
according to my stats-book, ANOVA actually can be used for non-parametric samples as well when n is over 30. dosen't say anything about its usefulness in lower numbers. I think I'll just have to agree with him and point out that the variation is so low, that any test would find them significant.
I've found a paper where the main evaluator used ANOVA in his WB-results with n=4, so maybe I'll have to point a finger at at him if I'm being attacked to hard (carreer suicide-option)
Edited by kottila, 10 January 2012 - 06:15 AM.