def set_independent_variables(data, dependent_variable):
    """
    Set independent variables.
    
    This helper functions isolates the independent variables in a data.frame.
    
    :param data: An object of class pandas.DataFrame; the data to be analyzed.
    :param dependent_variable: A string; the dependent variable for this analysis.
    :return: An object of class pandas.DataFrame; the independent variables of the analysis.
    """
    X = data.drop(dependent_variable, axis=1).values
    return X