code: def convenience_calc_probs(self, params):
          
          shapes, intercepts, betas = self.convenience_split_params(params)
  
          prob_args = [betas,
                       self.design,
                       self.alt_id_vector,
                       self.rows_to_obs,
                       self.rows_to_alts,
                       self.utility_transform]
  
          prob_kwargs = {"intercept_params": intercepts,
                         "shape_params": shapes,
                         "chosen_row_to_obs": self.chosen_row_to_obs,
                         "return_long_probs": True}
          prob_results = cc.calc_probabilities(*prob_args, **prob_kwargs)
  
          return prob_results
docs: Calculates the probabilities of the chosen alternative, and the long
          format probabilities for this model and dataset.