BLR_CLASSIFY: Binary Logistic Regression

Syntax: How to Calculate a Binary Logistic Regression

BLR_CLASSIFY(options, proba_flag, 
         predictor_field1[, predictor_field2, ...] target_field)

where:

options

Reserved for future use.

proba_flag

Keyword

Indicates whether to display probabilities. Valid values are PROBA, to display the probability of belonging to class 1, and NO_PROBA, to display class assignment.

When proba_flag has the value NO_PROBA, this function returns a binary-class prediction for Y (Y=0 or 1).
When proba_flag has the value PROBA, this function returns the probability Y (0<=Y<=1), that (X0, X1, . . .) belongs to class 1.

predictor_field1[, predictor_field2, ...]

Numeric

Are one or more predictor field names.

target_field

Numeric

Is the target field.

Example: Using BLR_CLASSIFY to Predict Education Code

The DEFINE FILE command in the following request creates two education levels, doctorate level (value 1) and no college education (value 0). It also creates other virtual fields with numeric formats that can be used by the function. The TABLE request uses BLR_CLASSIFY to compute the probability that the education level belongs to class 1, doctorate level education, using predictors age, income, population range, and gender.

DEFINE FILE WF_RETAIL
BINARY_EDUC_LEVEL/I2 =
DECODE WF_RETAIL_EDUCATION_CUSTOMER.EDUCATION_DEGREE_TYPE (
'Professional Doctorates' 1,
'Doctorates' 1,
'High School' 0,
'No High School' 0,
ELSE -1 );
POP_CODE/I2 =
DECODE WF_RETAIL_GEOGRAPHY_CUSTOMER.CITY_POPULATION_RANGE (
'H: 100,001 - 250,000' 1,
'I: 250,001 - 1,000,000' 2,
'J: 1,000,001 - 10,000,000' 3,
'K: 10,000,001 - 50,000,000' 4,
ELSE 0 );
GENDER_CODE/I2 =
DECODE WF_RETAIL_CUSTOMER.GENDER (
'M' 1, 'F' 0 );
END

TABLE FILE WF_RETAIL
PRINT
ID_CUSTOMER 
BINARY_EDUC_LEVEL
COMPUTE PREDICTED_PROB/D6.4=BLR_CLASSIFY(' ',PROBA,
                                             AGE,
                                             INCOME,
                                             POP_CODE,
                                             GENDER_CODE,
                                             BINARY_EDUC_LEVEL);
WHERE BINARY_EDUC_LEVEL NE -1
WHERE POP_CODE NE 0
WHERE INCOME GT 12001.00
WHERE OUTPUTLIMIT EQ 12
ON TABLE SET PAGE NOLEAD
ON TABLE SET STYLE *
GRID=OFF,$
ENDSTYLE
END

The partial output is shown in the following image.

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