PREDICT_NAIVE_BAYES_CLASSES

Applies a Naive Bayes model on an input relation and returns the probabilities of classes:.

Applies a Naive Bayes model on an input relation and returns the probabilities of classes:

  • VARCHAR predicted column contains the class label with the highest probability.

  • Multiple FLOAT columns, where the first probability column contains the probability for the class specified in the predicted column. Other columns contain the probability of belonging to each class specified in the classes parameter.

Syntax

PREDICT_NAIVE_BAYES_CLASSES ( predictor-columns
        USING PARAMETERS model_name = 'model-name'
            [, key_columns = 'key-columns']
            [, exclude_columns = 'excluded-columns]
            [, classes = 'classes']
            [, match_by_pos = match-by-position] )
OVER( [window-partition-clause] )

Arguments

predictor-columns
Comma-separated list of columns to use from the input relation, or asterisk (*) to select all columns.

Parameters

model_name

Name of the model (case-insensitive).

key_columns

Comma-separated list of predictor column names that identify the output rows. To exclude these and other predictor columns from being used for prediction, include them in the argument list for parameter exclude_columns.

exclude_columns
Comma-separated list of columns from predictor-columns to exclude from processing.
classes
Comma-separated list of class labels in the model. The probability of belonging to this given class as predicted by the classifier. The values are case sensitive.
match_by_pos
Boolean value that specifies how predictor columns are matched to model features:

  • false (default): Match by name.

  • true: Match by the position of columns in the predictor columns list.

Examples

=> SELECT PREDICT_NAIVE_BAYES_CLASSES (id, vote1, vote2 USING PARAMETERS
model_name='naive_house84_model',key_columns='id',exclude_columns='id',
classes='democrat, republican', match_by_pos='false')
        OVER() FROM house84_test;
 id  | Predicted  |    Probability    |     democrat      |    republican
-----+------------+-------------------+-------------------+-------------------
  21 | democrat   | 0.775473383353576 | 0.775473383353576 | 0.224526616646424
  28 | democrat   | 0.775473383353576 | 0.775473383353576 | 0.224526616646424
  83 | republican | 0.592510497724379 | 0.407489502275621 | 0.592510497724379
 102 | democrat   | 0.779889432167111 | 0.779889432167111 | 0.220110567832889
 107 | republican | 0.598662714551597 | 0.401337285448403 | 0.598662714551597
 125 | republican | 0.598662714551597 | 0.401337285448403 | 0.598662714551597
 132 | republican | 0.592510497724379 | 0.407489502275621 | 0.592510497724379
 136 | republican | 0.592510497724379 | 0.407489502275621 | 0.592510497724379
 155 | republican | 0.598662714551597 | 0.401337285448403 | 0.598662714551597
 174 | republican | 0.592510497724379 | 0.407489502275621 | 0.592510497724379
...
(1 row)

See also