"The field of study that gives computers the ability to learn without being explicitly programmed." - Arthur Samuel (1959)
"A computer program is said to learn from experience E with respect to some class of tasks T and performance measure P, if its performance at tasks in T, as measured by P, improves with experience E." - Tom Mitchell (1997)
e.g., playing a game
E: the experience of playing many games
T: the task of playing the game
P: the probability that the program will win the next game
In general, any machine learning problem can be assigned to one of two broad classifications:
- supervised learning and
- unsupervised learning.