How to use Isolation Forest

Question

I am trying to detect the outliers to my dataset and I find the sklearn\'s Isolation Forest. I can\'t understand how to work with it. I fit my training data in it and it giv

Answer 1

-1 represents the outliers (according to the fitted model). See IsolationForest example for a nice depiction of the process. If you have some prior knowledge, you could provide more parameters to get a more accurate fitting. For example, if you know the contamination (proportion of outliers in the data set) you could provide it as an input. By default it is assumed to be 0.1. See description of the parameters here.