'Returns parameter names (for alpha) for the summary.
Returns
param_names : list of str
Returns a list of parameter names for the loading coefficients
which are called :math:`\alpha` in [1]_ (see chapter 6).
References
.. [1] Lutkepohl, H. 2005. *New Introduction to Multiple Time Series Analysis*. Springer.'

@property
def _load_coef_param_names(self):

    param_names = []
    if (self.coint_rank == 0):
        return None
    param_names += [(self.load_coef_repr + ('%d.%s' % ((i + 1), self.endog_names[j]))) for j in range(self.neqs) for i in range(self.coint_rank)]
    return param_names
