bias与variance，欠拟合与过拟合关系

http://mp.weixin.qq.com/s?__biz=MzIzNDQyNjI5Mg==&mid=2247484087&idx=1&sn=0066fb41f5aa74d2b70433f00c56f0b8&chksm=e8f7d86cdf80517a98214abdc79074ea2b79d8b1e094aa0a8de66242342a43fc5ee7edb39043&mpshare=1&scene=24&srcid=1214KLUC6xQnQ3fvQ13rokss#rd
http://blog.csdn.net/hurry0808/article/details/78148756；