This function plots a Q-Q/Quantile-Quantile plot (qq) on a given data frame, and uses simplified calls within the function to parse the Q-Q plot by up to 2 variables.
Usage
qq(df, var1, by1, by2)
Value
This function returns the quantile-quantile plot for var1 in data frame df. Can be split to return a quantile-quantile plot for var1 in data frame df, broken out by var2.
Arguments
df
data frame to read in.
var1
the dependent/outcome variable, \(Y\). The variable of interest that should be plotted.
by1
the main independent/predictor variable, \(X_1\). A grouping variable by which the Q-Q plot for var1 should be parsed.
by2
a potential second independent/predictor variable, \(X_2\). A second grouping variable by which the Q-Q plot for var1 (already parsed by by1) should be parsed.