pairwiseNominalMatrix function

Pairwise tests of independence for nominal data with matrix output

Conducts pairwise tests for a 2-dimensional matrix, in which at at least one dimension has more than two levels, as a post-hoc test. Conducts Fisher exact, Chi-square, or G-test.

pairwiseNominalMatrix(
  x,
  compare = "row",
  fisher = TRUE,
  gtest = FALSE,
  chisq = FALSE,
  method = "fdr",
  correct = "none",
  digits = 3,
  ...
)

Arguments

• x: A two-way contingency table. At least one dimension should have more than two levels.
• compare: If "row", treats the rows as the grouping variable. If "column", treats the columns as the grouping variable.
• fisher: If "TRUE", conducts fisher exact test.
• gtest: If "TRUE", conducts G-test.
• chisq: If "TRUE", conducts Chi-square test of association.
• method: The method to adjust multiple p-values. See p.adjust.
• correct: The correction method to pass to DescTools::GTest.
• digits: The number of significant digits in the output.
• ...: Additional arguments, passed to stats::fisher.test, DescTools::GTest, or stats::chisq.test.

Returns

A list consisting of: the test used, a matrix of unadjusted p-values, the p-value adjustment method used, and a matrix of adjusted p-values.

Examples

### Independence test for a 4 x 2 matrix
data(Anderson)
fisher.test(Anderson)
Anderson = Anderson[(c("Heimlich", "Bloom", "Dougal", "Cobblestone")),]
PT = pairwiseNominalMatrix(Anderson,
                           fisher = TRUE,
                           gtest  = FALSE,
                           chisq  = FALSE)$Adjusted
PT
library(multcompView)
multcompLetters(PT)

References

https://rcompanion.org/handbook/H_04.html

See Also

pairwiseMcnemar, groupwiseCMH, nominalSymmetryTest, pairwiseNominalIndependence

Author(s)

Salvatore Mangiafico, mangiafico@njaes.rutgers.edu