SmartEDA (version 0.3.2)

ExpInfoValue: Information value

Description

Provides information value for each categorical variable (X) against target variable (Y)

Usage

ExpInfoValue(X, Y, valueOfGood = NULL)

Arguments

X

Independent categorical variable.

Y

Binary response variable, it can take values of either 1 or 0.

valueOfGood

Value of Y that is used as reference category.

Value

Information value (iv) and Predictive power class

information value

predictive class

Details

Information value is one of the most useful technique to select important variables in a predictive model. It helps to rank variables on the basis of their importance. The IV is calculated using the following formula

IV = (Percentage of Good event - Percentage of Bad event) * WOE, where WOE is weight of evidence

WOE = log(Percentage of Good event - Percentage of Bad event)

Here is what the values of IV mean according to Siddiqi (2006)

If information value is < 0.03 then predictive power = "Not Predictive"

If information value is 0.03 to 0.1 then predictive power = "Somewhat Predictive"

If information value is 0.1 to 0.3 then predictive power = "Meidum Predictive"

If information value is >0.3 then predictive power = "Highly Predictive"

See Also

IV

Examples

# NOT RUN {
X = mtcars$gear
Y = mtcars$am
ExpInfoValue(X,Y,valueOfGood = 1)
# }