st: boxtid & linearity

[SR Millis <srmillis@mindspring.com>]

I've run a logistic regression model. I wanted to evaluate whether there was substantial nonlinarity in the logit, so I used the Box-Tidwell transformation and found that there was nonlinearity, as shown in the following output. However, when I followed up with mfracpol, I wasn't able to find any alternative tranformation.  Any suggestion?

Thanks,
SR Millis 

note: 0 failures and 16 successes completely determined.
ldfr     |  -.2405828   .0990139     -2.430   Nonlin. dev. 9.295   (P = 0.002)
     p1 |   4.520587   2.083727      2.169
------------------------------------------------------------------------------
sdfr     |   .2828134   .1111305      2.545   Nonlin. dev. 5.292   (P = 0.021)
     p1 |   3.944163   1.872817      2.106
------------------------------------------------------------------------------
hits     |  -.6063142   .1097356     -5.525   Nonlin. dev. 3.331   (P = 0.068)
     p1 |  -2.475662   2.074093     -1.194
------------------------------------------------------------------------------
Deviance:  117.923.




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