Bias and Variance in Logistic Regression in SAS

[aranganayagi]

HI, How do I check built Logistic regression model is suffering with BIAS or Variance.

I learnt about c-statistics, H-L Goodness -of-Fit Statistics, they all say how well the model is fit. But how can I interpret that the built model will perform better in unseen data. Please help to understand. Really struggling to get answer to this.

[aranganayagi]

Can anyone help me on this

[Ksharp · Accepted solution]

I don't understand your Q well.

1) if you want know if model is robust , 

You can use train data and test data to check model . or

n-fold cross validate method( split your data into ten group, using 9 of 10 to build model and 1 of 10 to test, and again using another 9 of 10 to build model and 1 of 10 to test , over and over again for ten times).

2)if you want know if data is over disperse. try 

proc logistic......

model ..../scale=none aggregate ;

3) if your train data is sample from a big table . you need 

model ............./ offset=  

to adjust your predict probability .