HolmTest: Holm-Adjusted Pairwise Comparisons v2.0

In Analitica: Exploratory Data Analysis, Group Comparison Tools, and Other Procedures

Holm-Adjusted Pairwise Comparisons v2.0

Description

Performs pairwise t-tests with p-values adjusted using Holm’s sequential method.

Usage

HolmTest(modelo, comparar = NULL, alpha = 0.05)

Arguments

modelo	An aov or lm object (full model: includes blocks, factors, etc.).
comparar	Character vector with the name(s) of the factor(s) to compare: - One name: main effect (e.g., "treatment" or "A") - Several names: interaction (e.g., c("A","B") for A:B) If omitted, it uses the first factor in modelo$xlevels.
alpha	Significance level (default 0.05).

Details

Advantages: - Controls family-wise error rate more efficiently than Bonferroni. - Easy to apply over any set of p-values.

Disadvantages: - Does not adjust test statistics, only p-values. - Slightly more conservative than false discovery rate (FDR) methods.

Value

An object of class "holm" and "comparaciones" containing:

• Resultados: a data.frame with columns Comparacion, Diferencia, SE, t_value, p_value (unadjusted), p_ajustada (Holm), Valor_Critico (critical difference), and Significancia.

• Promedios: a named vector of group means as defined by comparar.

• Orden_Medias: group names ordered from highest to lowest mean.

• Metodo: "Holm t-test".

• Termino: the term being compared (e.g., "A", "B", or "A:B").

• MSerror, df_error, N: useful for plots with error bars.

References

Holm, S. (1979). A simple sequentially rejective multiple test procedure.Scandinavian Journal of Statistics, 6(2), 65–70.

Examples

data(d_e, package = "Analitica")
mod <- aov(Sueldo_actual ~ as.factor(labor), data = d_e)
resultado <- HolmTest(mod)
summary(resultado)
plot(resultado)

# RCBD
mod <- aov(Sueldo_actual ~ as.factor(labor) + Sexo, data = d_e)
res <- HolmTest(mod, comparar = "as.factor(labor)")
summary(res); plot(res)                # usa p_ajustada automaticamente

# Factorial
mod2 <- aov(Sueldo_actual ~ as.factor(labor) * Sexo, data = d_e)
resAB <- HolmTest(mod2, comparar = c("as.factor(labor)","Sexo"))
summary(resAB, n = Inf); plot(resAB, horizontal = TRUE)

Analitica documentation built on Nov. 5, 2025, 5:13 p.m.