Isotonic regression in Apache Spark 2.0
In this recipe, we demonstrate the IsotonicRegression()
function in Spark 2.0. The isotonic or monotonic regression is used when order is expected in the data and we want to fit an increasing ordered line (that is, manifest itself as a step function) to a series of observations. The terms isotonic regression (IR) and monotonic regression (MR) are synonymous in literature and can be used interchangeably.
In short, what we are trying to do with the IsotonicRegression()
recipe is to provide a better fit versus some of the shortcomings of Naive Bayes and SVM. While they are both powerful classifiers, Naive Bayes lacks a good estimate of P (C | X) and Support Vector Machines (SVM) at best provides only a proxy (can use hyperplane distance), which is not an accurate estimator in some cases.
How to do it...
- Go to the website to download the file and save the file into the data path mentioned in the following code blocks. We use the famous Iris data and fit a...