Parameters
		----------
		cat_word_counts : np.array
			category counts
		not_cat_word_counts : np.array
			not category counts

		Returns
		-------
		np.array
			scores

def get_scores(self, cat_word_counts, not_cat_word_counts):
		'''
		Parameters
		----------
		cat_word_counts : np.array
			category counts
		not_cat_word_counts : np.array
			not category counts

		Returns
		-------
		np.array
			scores
		'''
		cat_scores = self.get_scores_for_category(cat_word_counts,
		                                          not_cat_word_counts)
		not_cat_scores = self.get_scores_for_category(not_cat_word_counts,
		                                              cat_word_counts)
		if self.use_score_difference_:
			scores = ((cat_scores - not_cat_scores) + 1.)/2.
		else:
			scores = ScoreBalancer.balance_scores(cat_scores, not_cat_scores)
		if self.one_to_neg_one_:
			return 2 * scores - 1
		else:
			return scores