Section 6.13 Key Functions & Commands
The following functions and commands are introduced or reinforced in this chapter to support categorical data analysis, contingency tables, and Chi-Square testing.
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table()(base R)-
Creates basic contingency (frequency) tables for categorical variables.
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xtabs()(base R)-
Constructs contingency tables using a formula interface, useful for multi-way tables.
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tabyl()(janitor)-
Generates clean contingency tables that integrate easily with percentage calculations.
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adorn_percentages()(janitor)-
Converts contingency table counts into row- or column-based percentages.
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adorn_ns()(janitor)-
Displays counts and percentages together for clearer interpretation.
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chisq.test()(stats)-
Performs a Chi-Square test of independence to assess whether two categorical variables are related.
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CrossTable()(gmodels)-
Produces detailed cross-tabulations including expected counts, proportions, and chi-square contributions.
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pheatmap()(pheatmap)-
Visualizes Chi-Square contributions or residuals using a heatmap.
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cramerV()(rcompanion)-
Computes Cramer’s V to measure the strength of association between categorical variables.
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