Assumptions
The results of a one-way ANOVA can be considered reliable as long as the following assumptions are met:
- Response variable are normally distributed (or approximately normally distributed).
- Samples are independent.
- Variances of populations are equal.
- Responses for a given group are independent and identically distributed normal random variables (not a simple random sample (SRS)).
ANOVA is a relatively robust procedure with respect to violations of the normality assumption. If data are ordinal, a non-parametric alternative to this test should be used such as Kruskal–Wallis one-way analysis of variance.
Read more about this topic: One-way ANOVA
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