def plot_leverages(self):
        """
        Leverage (h) per observation, with a red line plotted at y = 1/Number of samples (expected
        :return: Plot with observation leverages (h)
        """
        plt.figure()
        lev = self.leverages()
        plt.xlabel('Sample Index')
        plt.ylabel('Leverage')
        plt.bar(left=range(lev.size), height=lev)
        plt.hlines(y=1/lev.size, xmin=0, xmax=lev.size, colors='r', linestyles='--')
        plt.show()
        return None