Logistic regression classifiers are often deployed with a threshold rather than the provided
classifier.bestCategory() method. This method picks the category with the highest conditional probability, which, in a 3-way classifier, can be just above one-third. This recipe will show you how to adjust classifier performance by explicitly controlling how the best category is determined.
This recipe will consider the 3-way case with the
o labels and work with the classifier produced by the Classifier-building life cycle recipe earlier in this chapter. The cross-validation evaluation produced is:
Category p Recall: 0.64 Prec : 0.57 Category n Recall: 0.41 Prec : 0.54 Category o Recall: 0.81 Prec : 0.81
We will run novel ...