Artificial Neural Network Prediction of Major League Baseball

Artificial Neural Network Prediction of Major League Baseball Teams Winning Percentages Scott Wiese ECE 539 Professor Hu

Motivation Current trends in managing player personnel focuses heavily on statistics to weigh future production against potential salaries. n n Used to determine whether or not to sign specific players Determine if current players are overpaid

Motivation Claimed that statistics can be a valid predictor of both a player’s and team’s production Claimed that one season, 162 games, is a long enough trial period that statistics can predict a team’s winning percentage

Goals Can I develop an artificial neural network that when given a team’s statistics for a year that will accurately predict a team’s winning percentage?

Data Collection Collected 3 years of data for all 30 Major League Baseball teams n n Gathered from statistical database available on www. MLB. com 74 statistics besides winning percentage gathered

Neural Network Selection Back Trained Multi Layer Perceptron n Excellent at analyzing large feature sets Supervised Training Good at classification problems

Preprocessing Normalized each feature vector Used singular value decomposition to emphasize most important features

Testing Wanted to determine which MLP configuration would best predict winning percentage n n Baseline MLP: 1 hidden layer, 1 hidden neuron Tested MLPs: 1 through 5 hidden layers, 1, 3, or 5 hidden neurons in all layers

Testing Results

Testing Now that we know the 4 hidden layers, 1 hidden neuron network performed the best, test it against the baseline with new data Success when predicted winning percentage within +/- 0. 15

Testing Results Best MLP’s performance almost twice as good as baseline’s performance.

Preliminary Conclusions Advanced MLP structure is better at predicting a team’s winning percentage. Unfortunately, still under 50% given a. 15 error bound Can classification work better

Classification Testing Classify teams into 3 groups n n n Division winners (>. 590) Winning teams (. 500<x<. 589) Losing teams (<. 500) Same process as above

Classification Results 3 hidden layers with 5 hidden neurons is best

Classification Results

Classification Results Again, now that we know the best advanced network, test it against the baseline with more data.

Classification Results Negligible difference between the two networks even though there was nearly a 50% improvement in the original trial.

Conclusions Advanced network better at pure prediction than baseline n Still a very moderate success rate given the error bounds Classification results very promising n Shows that statistics are important in separating teams’ results