According to the documentation ( SimpleLogistic and Logistic ), SimpleLogistic uses LogitBoost, while Logistic uses crest evaluation. In the papers describing the algorithms,
Niels Landver, Mark Hall, Abe Frank (2005). Trees logistic model. Machine Learning 95 (1-2): 161-205 for SimpleLogistic
le Cessie, S., van Houwelingen, JC (1992). Range estimates in logistic regression. Applied statistics. 41 (1): 191-201 for logistics.
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