这篇讲得比较好理解: http://blog.csdn.net/v_july_v/article/details/40718799
老外的这篇更清晰: http://mccormickml.com/2013/12/13/adaboost-tutorial/
然后github上有一个可读性比较好的案例: https://github.com/fengchangfight/NaiveBayesSpamFilter
来自机器学习实战的案例: https://github.com/apachecn/MachineLearning/tree/master/src/python/7.AdaBoost