Check normality for groups

Check normality for groups

Usage

check_normality_by_group(data, x, y)

Arguments

data

the data frame

x

the x column

y

the y column

Value

TRUE if all groups are normal, FALSE otherwise. The per-group Shapiro-Wilk statistics are attached as a data frame in the "tests" attribute (columns: group, W, p_value), e.g. for use in a methods section via assumption_methods_text(). For groups with more than 5000 non-missing values, Shapiro-Wilk is computed on a random sample of 5000 observations (a warning is emitted); the returned value still reflects that sampled test. Because the sample is drawn randomly, results for such large groups are not reproducible unless a seed is set beforehand.