Stanford机器学习课程之一——引言

Andrew Ng的Machine Learning课程，在网易公开课上有中文版视频http://v.163.com/special/opencourse/machinelearning.html，六维上也有资源可以下载。

引言

machine learning 定义1：Field of study that gives computers the ability to learn without being explicitly programmed.

machine learning 定义2：A computer program is said to learn from experience E with respect to some tast T and some performance measure P, if its performance on T, as measured by P, improves with experience E.

课程主要包括四个部分：

1：Supervised Learning监督学习

Regression回归

Classification分类

2：Learning Theory学习理论

理解学习算法how and why work

3：Unsupervised Learning非监督学习

Clustering聚类

主要应用：基因分析、图像处理、社交网络分析、市场划分...

4:Reinforcement Learning强化学习

需要做一系列决策（例如：无人驾驶飞机，机器人领域），设置reward function