吴恩达《Machine Learning》-概念（一）

入坑吴恩达大佬的机器学习课程。纯英文教学和作业还有编程作业还是很挑战的，希望早日结课拿证。

机器学习定义

T是此次机器学习的任务

测试题：

“A computer program is said to learn from experience E with respect to some task T and some performance measure P, if its performance on T, as measured by P, improves with experience E.”
Suppose your email program watches which emails you do or do not mark as spam, and based on that learns how to better filter spam. What is the task T in this setting?

A.Classify emails as spam or not spam.

B.Watching you label emails as spam or not spam.

C.The number (or fraction) of emails correctly classified as spam/not spam.

D.None of the above, this is not a machine learning algorithm.

问题：此次的任务是什么？

正确答案：

选择A，将邮件分为垃圾邮件与非垃圾邮件
为Task

B，看你把邮件贴上垃圾邮件或者不是垃圾邮件的标签
为Experience

C，正确分类为垃圾邮件/非垃圾邮件的电子邮件的数量
为Performance

详细定义

Two definitions of Machine Learning are offered. Arthur Samuel described it as: “the field of study that gives computers the abili