Accurate estimation of software development effort is a very difficult job. Both under estimation as well as over estimation can lead to serious consequences. So it's very important to find a technique which can yield accurate results for software effort estimation. Here in the authors' paper they have evaluated various machine learning techniques for software effort estimation like bagging, decision trees, decision tables, multilayer perceptron and RBF networks. Two different datasets i.e. heiatheiat dataset and miyazaki94 dataset have been used in their paper.