Hi David,

> As I understand it now the 0 probability is probability that the prediction is wrong, and the 1 probability is the probability that the prediction is correct

No: in binary classification, the `predict_proba` method returns a single number in [0, 1] indicating the probability that the sample belongs to the positive class (1). In other words,   (proba <= 0.5  iff prediction == 0). The threshold is 0.5 since there are only 2 classes.

> One thing I do not understand is why the probability ranges do not go from 0 to 100; they go from 0 to 49 for 0 probability and 49-100 for 1 probability

This is a correct observation and it's a direct consequence of the above definition.

The way probabilities are computed is briefly described here: https://scikit-learn.org/stable/modules/generated/sklearn.ensemble.RandomForestClassifier.html#sklearn.ensemble.RandomForestClassifier.predict_proba

Nicolas

On 12/28/20 2:36 AM, DAVID cofield wrote:

Could someone explain what the probability values provided by the random forest classifier represents?

When I run the classifier with two classes, I get prediction values and associated to these prediction values are probabilities. As I understand it now the 0 probability is probability that the prediction is wrong, and the 1 probability is the probability that the prediction is correct. One thing I do not understand is why the probability ranges do not go from 0 to 100; they go from 0 to 49 for 0 probability and 49-100 for 1 probability. How do I interpret  the probabilities?

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