--- Pabst Alexander wrote:
> I'd like to estimate a logistic regression model with an interaction
> term between a continuous predictor (X1) and another but ln-transformed
> continuous predictor (X2)
The best way of making sense of such highly non-linear models is to
graph the results:
*--------------------- begin example --------------------------------
sysuse nlsw88, clear
gen lngrade = ln(grade)
gen southXlngrade = south*lngrade
logit union lngrade south southXlngrade married never_married
adjust married = 1 never_married = 0, by(grade south) ci replace pr
twoway rarea lb ub grade if south == 0 || ///
rarea lb ub grade if south == 1 || ///
line pr grade if south == 0 || ///
line pr grade if south == 1, ///
legend(order( 3 "Non-South" ///
4 "South")) ///
ytitle("probability union worker")
*--------------------- end example ----------------------------------
Hope this helps,
Maarten
-----------------------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
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