Editing Temporal difference learning (section)

== TD-Lambda ==
'''TD-Lambda''' is a learning algorithm invented by [[Richard S. Sutton]] based on earlier work on temporal difference learning by [[Arthur Samuel (computer scientist)|Arthur Samuel]].{{sfnp|Sutton|Barto|2018|p=130?}} This algorithm was famously applied by [[Gerald Tesauro]] to create [[TD-Gammon]], a program that learned to play the game of [[backgammon]] at the level of expert human players.{{sfnp|Tesauro|1995}}

The lambda (<math>\lambda</math>) parameter refers to the trace decay parameter, with <math>0 \leqslant \lambda \leqslant 1</math>. Higher settings lead to longer lasting traces; that is, a larger proportion of credit from a reward can be given to more distant states and actions when <math>\lambda</math> is higher, with <math>\lambda = 1</math> producing parallel learning to Monte Carlo RL algorithms.{{sfnp|Sutton|Barto|2018|p=175}}