Logistic regression coefficients problem

Question

I'm using logistic regression model to do a multi-class classification (4 classes). I want to look at the logistic regression coefficients to see the importance of different features. I got model output from a software that looks like:

Coefficients...
                                   Class
Variable                           other                  price                  image
======================================================================================
titleInAttr                      -3.5443                 7.5539               -15.8454
location                        929.1475              1900.9971                1040.68
inList                          -13.2383               -10.5824               -12.7287
imgprop                           8.9593                22.5193                13.9187
priceInAttr                       1.1979                34.0779               -25.0851

Here, only 3 classes are shown, so I wonder how to get the coefficients for the fourth class? Is it usually unnecessary to show coefficients for all classes? I'd like to know how to calculate the missing ones from the results. Thanks a lot.

Answer 1

You cannot get coefficients for the fourth class. The fourth class is the "baseline" case. All coefficients are relative to that one. See here for more information.