Internal helper function that examines the class of variables in the subset data to determine their types (factor, numeric, character, etc.).
detect_variable_types(subset_data, dep_crwd, indep_crwd)List with two elements:
dep: Character vector of classes for dependent variables
indep: Character vector of classes for independent variables (empty if none)
Data frame subset containing the relevant variables
Character vector of dependent variable names for current crowd
Character vector of independent variable names for current crowd