Using R and RStudio for Data Management, Statistical Analysis, and Graphics, 2nd Edition

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“K23166” — 2015/1/28 — 9:35 — page 56 — #82

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56 CHAPTER 5. COMMON STATISTICAL PROCEDURES

possible confounding effects of X

3

without having to estimate parameters for them.

mantelhaen.test(x1, x2, x3)

5.3.5 Cram´er’s V

Cram´er’s V (or phi coefficient) is a measure of association for nominal variables.

library(vcd)

assocstats(table(x, y))

5.3.6 Fisher’s exact test

Example: 5.7.3

fisher.test(y, x)

or

fisher.test(ymat)

Note: The fisher.test() command can accept either two class vectors or a table of counts

(here denoted by ymat). For tables with many rows and/or columns, p-values can be

computed using Monte Carlo simulation using the simulate.p.value option. ...