Suppose on performing reduced error pruning, we collapsed a node and observed an improvement in the prediction accuracy on the validation set.Which among the following statements are possible in light of the performance improvement observed? ( a) The collapsed node helped overcome the effect of one or more noise affected data points in the training set ( b) The validation set had one or more noise affected data points in the region corresponding to the collapsed node ( c) The validation set did not have any data points along at least one of the collapsed branches ( d) The validation set did have data points adversely affected by the collapsed node

Machine learning (ML) is a branch of artificial intelligence that leverages data to improve computer performance by giving machines the ability to "learn", or improve performance — based on the data.

There are four basic approaches to machine learning: supervised learning, unsupervised learning, semi-supervised learning and reinforcement learning.