Creates Covariance Matrix for a given Beta Vector
        (Not necessarily the OLS covariance)

        Parameters
        ----------
        beta : np.array
            Contains untransformed starting values for latent variables

        Returns
        ----------
        A Covariance Matrix

def custom_covariance(self,beta):
        """ Creates Covariance Matrix for a given Beta Vector
        (Not necessarily the OLS covariance)

        Parameters
        ----------
        beta : np.array
            Contains untransformed starting values for latent variables

        Returns
        ----------
        A Covariance Matrix
        """         

        cov_matrix = np.zeros((self.ylen,self.ylen))
        parm = np.array([self.latent_variables.z_list[k].prior.transform(beta[k]) for k in range(beta.shape[0])])
        return custom_covariance_matrix(cov_matrix, self.ylen, self.lags, parm)