IDAX.CMATRIX_WACC - Calculate the weighted classification accuracy from a confusion matrix

Use this stored procedure to calculate the weighted ratio of correctly classified predictions among the total number of predictions from a confusion matrix. For the calculation of the ratio, each class has the same weight, irrespective of its real frequency in the input data. This approach is useful when classes are not equally frequent.

Authorization

The privileges held by the authorization ID of the statement must include the IDAX_USER role.

Syntax

IDAX.CMATRIX_WACC(in parameter_string varchar(32672))

Parameter descriptions

parameter_string

Mandatory one-string parameter that contains pairs of <parameter>=<value> entries that are separated by a comma.

Data type: VARCHAR(32672)

The following list shows the parameter values:

matrixTable: Mandatory.; The name of the confusion matrix table.; Data type: VARCHAR(256)

Returned information

Double the weighted classification accuracy as a result set.

Example

CALL IDAX.SPLIT_DATA('intable=samples.customer_churn,traintable=cust_train,testtable=cust_test,id=cust_id,fraction=0.30');
CALL IDAX.GROW_DECTREE('model=cust_dt, intable=cust_train, id=cust_id, target=censor, incolumn=duration:ignore;censor:nom, minsplit=2');
CALL IDAX.PREDICT_DECTREE('model=cust_dt, intable=cust_test, outtable=cust_dt_out');
CALL IDAX.CONFUSION_MATRIX('intable=cust_test, id=cust_id, target=censor, resulttable=cust_dt_out, matrixtable=cust_dt_cm');
CALL IDAX.CMATRIX_WACC('matrixTable=cust_dt_cm');