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Indexes:

anova-one-way-variables (iv dv &optional (scheffe-tests-p t)

confidence-intervals)

Performs a one-way analysis of variance (ANOVA) on the input data, which

should be two equal-length sequences: ` iv' is the independent variable,<br> represented as a sequence of categories or group identifiers, and `

dv' is the

dependent variable, represented as a sequence of numbers. The ` iv' variable<br> must be `

` sorted,'' meaning that AAABBCCCCCDDDD is okay but ABCDABCDABDCDC is<br> not, where A, B, C and D are group identifiers. Furthermore, each group should<br> consist of at least 2 elements.<br> <br> The significance of the result indicates that the group means are not all equal;<br> that is, at least two of the groups have significantly different means. If<br> there were only two groups, this would be semantically equivalent to an<br> unmatched, two-tailed t-test, so you can think of the one-way ANOVA as a<br> multi-group, two-tailed t-test.<br> <br> This function returns five values: 1. an ANOVA table; 2. a list a group<br> means; 3. either a Scheffe table or nil depending on `

scheffe-tests-p'; and

4. an alternate value for SST. 5. a list of confidence intervals in the form` (,mean ,lower ,upper) for each group, if `

confidence-intervals' is a number

between zero and one, giving the kind of confidence interval, such as 0.9. The

fourth value is only interesting if you think there are numerical accuracy

problems; it should be approximately equal to the SST value in the ANOVA

table. This function differs from `anova-one-way-groups' only in its input

representation. See the manual for more information.