contr_code_difference {faux} | R Documentation |
Difference code a factor
Description
Difference coding sets the grand mean as the intercept. Each contrast compares one level with the previous level.
Usage
contr_code_difference(fct, levels = NULL, colnames = NULL)
Arguments
fct |
the factor to contrast code (or a vector) |
levels |
the levels of the factor in order |
colnames |
optional list of column names for the added contrasts |
Value
the factor with contrasts set
Examples
df <- sim_design(between = list(pet = c("cat", "dog", "ferret")),
mu = c(2, 4, 9), empirical = TRUE, plot = FALSE)
df$pet <- contr_code_difference(df$pet)
lm(y ~ pet, df) %>% broom::tidy()
[Package faux version 1.2.2 Index]