KDE_PI_adapt_lognorm_power
                        Adaptive log-normal plug-in density estimator
                        for power transformations.
KDE_PI_adapt_norm       Adaptive normal PI estimate in the case of the
                        logarithmic transformation.
KDE_ln_PI               The PI kernel density estimate in the case of
                        the logarithmic transformation.
KDE_power_PI            The PI kernel density estimate in the case of
                        the power transformation.
h_ln_PI                 The bandwidth for the single-bandwidth PI
                        density estimator in the case of the
                        logarithmic transformation.
h_pi_datadriven_power   The bandwidth for the single-bandwidth PI
                        density estimator for data after the power
                        transformation with an exponent ranging from
                        zero to one based on the Gaussian kernel.
