Snippet Name: PREDICTION_SET
Description: PREDICTION_SET is for use with classification models created using the DBMS_DATA_MINING package or with the Oracle Data Mining Java API. It is not valid with other types of models. It returns a varray of objects containing all classes in a multiclass classification scenario. The object fields are named PREDICTION, PROBABILITY, and COST. The datatype of the PREDICTION field depends on the target value type used during the build of the model. The other two fields are both Oracle NUMBER. The elements are returned in the order of best prediction to worst prediction.
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For bestN, specify a positive integer to restrict the returned target classes to the N having the highest probability, or lowest cost if cost matrix clause is specified. If multiple classes are tied in the Nth value, then the database still returns only N values. If you want to filter only by cutoff, specify NULL for this parameter.
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For cutoff, specify a NUMBER value to restrict the returned target classes to those with a probability greater than or equal to (or a cost less than or equal to if cost matrix clause is specified) to the specified cutoff value. You can filter solely by cutoff by specifying NULL for bestN.
When you specify values for both bestN and cutoff, you restrict the returned predictions to only those that are the bestN and have a probability (or cost when the cost_matrix_clause is specified) surpassing the threshold.
The cost_matrix_clause clause is relevant for all classification models. When you specify this clause, both bestN and cutoff are treated with respect to the prediction cost, not the prediction probability. The value of bestN restricts the result to the target classes having the N best (lowest) costs, and cutoff restricts the target classes to those with a cost less than or equal to the specified cutoff.
When you specify this clause, each object in the collection is a triplet of scalar values containing the prediction value (the datatype of which depends on the target value type used during model build), the prediction probability, and the prediction cost (both Oracle NUMBER).
If you omit this clause, then each object in the varray is a pair of scalars containing the prediction value and prediction probability.
Also see:
» PREDICTION_PROBABILITY
» PREDICTION_DETAILS
» PREDICTION_COST
» PREDICTION_BOUNDS
» PREDICTION
» FEATURE_SET
» FEATURE_ID
» CLUSTER_SET
» CLUSTER_PROBABILITY
» CLUSTER_ID
Comment: (none)
Language: PL/SQL
Highlight Mode: PLSQL
Last Modified: March 07th, 2009
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PREDICTION_SET(<schema.model>, <best N>, <cutoff>
<cost_matrix_clause> <mining_attribute_clause>)
SELECT T.cust_id, S.prediction, S.probability, S.cost
FROM (SELECT cust_id,
PREDICTION_SET(dt_sh_clas_sample COST MODEL USING *) pset
FROM mining_data_apply_v
WHERE cust_id < 100011) T,
TABLE(T.pset) S
ORDER BY cust_id, S.prediction;
CUST_ID PREDICTION PROBABILITY COST
---------- ---------- ----------- -----
100001 0 .96682 .27
100001 1 .03318 .97
100002 0 .74038 2.08
100002 1 .25962 .74
100003 0 .90909 .73
100003 1 .09091 .91
100004 0 .90909 .73
100004 1 .09091 .91
100005 0 .27236 5.82
100005 1 .72764 .27
100006 0 1.00000 .00
100006 1 .00000 1.00
100007 0 .90909 .73
100007 1 .09091 .91
100008 0 .90909 .73
100008 1 .09091 .91
100009 0 .27236 5.82
100009 1 .72764 .27
100010 0 .80808 1.54
100010 1 .19192 .81
20 rows selected.
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