Good implementations of reinforcement learning?

Take a look at the 2009 RL-competition. One of the problem domains is a tetris game. There was a tetris problem the year before too. Here’s the 52-page final report from that year’s fifth-place finalist, which goes into a lot of detail about how the agent worked.

The Heaton Research ebook is quite good at explaining neural network concepts (with code). Chapter 4 is dedicated to machine learning and the various training methods for your networks. There is a downloadable library and sample applications for you to look at.

Here is a good book on the subject:

Machine Learning and Data Mining: Introduction to Principles and Algorithms
by Igor Kononenko, Matjaz Kukar (June, 2007)

Also take a look at these open source projects:

• Maja Machine Learning Framework
• PIQLE
• Elsy
• The Robotics Primer Workbook

TD-Gammon, gnubackgammon, or any other similar project were massive successes in games.

Sutton & Barto's book "Reinforcement Learning: An Introduction" also has some other Case Studies.