Esempio n. 1
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 def infer_distribution(self):
     if self.is_categorical:
         distribution = self.data_dropna.value_counts()
         for value in set(self.distribution_bins) - set(distribution.index):
             distribution[value] = 0
         distribution.sort_index(inplace=True)
         self.distribution_probabilities = normalize_given_distribution(distribution)
         self.distribution_bins = np.array(distribution.index)
     else:
         distribution = np.histogram(self.data_dropna_len, bins=self.histogram_size)
         self.distribution_bins = distribution[1][:-1]
         self.distribution_probabilities = normalize_given_distribution(distribution[0])
    def infer_distribution(self):
        if self.is_categorical:
            histogram = self.data_dropna.value_counts()
            for value in set(self.distribution_bins) - set(histogram.index):
                histogram[value] = 0
            histogram = histogram[self.distribution_bins]
            self.distribution_probabilities = normalize_given_distribution(
                histogram)

        else:
            histogram, _ = np.histogram(self.data_dropna,
                                        bins=self.distribution_bins)
            self.distribution_probabilities = normalize_given_distribution(
                histogram)
    def _construct_conditional_probabilities(self, bayesian_network,
                                             encoded_dataset):
        k = len(bayesian_network[-1][1])
        conditional_distributions = {}

        # first k+1 attributes
        root = bayesian_network[0][1][0]
        kplus1_attributes = [root]
        for child, _ in bayesian_network[:k]:
            kplus1_attributes.append(child)

        freqs_of_kplus1_attributes = self._get_attribute_frequency_counts(
            kplus1_attributes, encoded_dataset)

        # get distribution of root attribute
        root_marginal_freqs = freqs_of_kplus1_attributes.loc[:, [
            root, 'count'
        ]].groupby(root).sum()['count']
        conditional_distributions[root] = normalize_given_distribution(
            root_marginal_freqs).tolist()

        for idx, (child, parents) in enumerate(bayesian_network):
            conditional_distributions[child] = {}

            if idx < k:
                stats = freqs_of_kplus1_attributes.copy().loc[:, parents +
                                                              [child, 'count']]
            else:
                stats = self._get_attribute_frequency_counts(
                    parents + [child], encoded_dataset)

            stats = DataFrame(
                stats.loc[:, parents +
                          [child, 'count']].groupby(parents + [child]).sum())

            if len(parents) == 1:
                for parent_instance in stats.index.levels[0]:
                    dist = normalize_given_distribution(
                        stats.loc[parent_instance]['count']).tolist()
                    conditional_distributions[child][str([parent_instance
                                                          ])] = dist
            else:
                for parents_instance in product(*stats.index.levels[:-1]):
                    dist = normalize_given_distribution(
                        stats.loc[parents_instance]['count']).tolist()
                    conditional_distributions[child][str(
                        list(parents_instance))] = dist

        return conditional_distributions
    def infer_distribution(self):

        histogram = self.data_dropna.value_counts()
        for attr_cat in set(self.distribution_bins) - set(histogram.index):
            histogram[attr_cat] = 0
        histogram = histogram[self.distribution_bins]
        self.distribution_probabilities = normalize_given_distribution(
            histogram)
Esempio n. 5
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 def infer_distribution(self):
     frequency_counts, _ = histogram(self.data_dropna,
                                     bins=self.distribution_bins)
     self.distribution_probabilities = normalize_given_distribution(
         frequency_counts)