Q: 什么是regression test以及为什么做regression test? A: fixing1进到build之后,QA/tester要进行手动测试,也可能会写automation.但是随后会有很多的其他的fixing进入到build,可能导致之前的fixing不工作了,为了确保之前的fixing和后续的fixing都能正常工作,QA需要针对fixing1再做一次test,叫做regression test. Q: 哪些bug/incident/SPR(software proble…

最近在研究机器学习,使用的工具是spark,本文是针对spar最新的源码Spark1.6.0的MLlib中的logistic regression, linear regression进行源码分析,其理论部分参考:http://www.cnblogs.com/ljy2013/p/5129610.html 下面我们跟随我的demo来一步一步解剖源码,首先来看一下我的demo: package org.apache.spark.mllib.classification import org.apac…

This is the 2nd part of the series. Read the first part here: Logistic Regression Vs Decision Trees Vs SVM: Part I In this part we’ll discuss how to choose between Logistic Regression , Decision Trees and Support Vector Machines. The most correct ans…

Regularized Linear Regression with scikit-learn Earlier we covered Ordinary Least Squares regression. In this posting we will build upon this foundation and introduce an important extension to linear regression, regularization, that makes it applicab…

In this note, we discuss principal components regression and some of the issues with it: The need for scaling. The need for pruning. The lack of “y-awareness” of the standard dimensionality reduction step. The purpose of this article is to set the st…

二分类:SVMs,logistic regression,decision trees,random forests,gradient-boosted trees,naive Bayes 多分类:             logistic regression,decision trees,random forests,                                        naive Bayes 归回:      linear least regression,   …

Logistic Regression with a Neural Network mindset You will learn to: Build the general architecture of a learning algorithm, including: Initializing parameters(初始化参数) Calculating the cost function and its gradient(计算代价函数,和他的梯度) Using an optimization…

Logistic Regression with a Neural Network mindset Welcome to the first (required) programming exercise of the deep learning specialization. In this notebook you will build your first image recognition algorithm. You will build a cat classifier that r…

在spark.ml中,实现了加速失效时间(AFT)模型,这是一个用于检查数据的参数生存回归模型. 它描述了生存时间对数的模型,因此它通常被称为生存分析的对数线性模型. 不同于为相同目的设计的比例风险模型,AFT模型更容易并行化,因为每个实例独立地贡献于目标函数. 当在具有常量非零列的数据集上匹配AFTSurvivalRegressionModel而没有截距时,Spark MLlib为常量非零列输出零系数. 这种行为不同于R survival :: survreg. 导入包 import org.…

回归正则化方法(Lasso,Ridge和ElasticNet)在高维和数据集变量之间多重共线性情况下运行良好. 数学上,ElasticNet被定义为L1和L2正则化项的凸组合: 通过适当设置α,ElasticNet包含L1和L2正则化作为特殊情况.例如,如果用参数α设置为1来训练线性回归模型,则其等价于Lasso模型.另一方面,如果α被设置为0,则训练的模型简化为ridge回归模型. RegParam:lambda>=0ElasticNetParam:alpha in [0, 1] 导入包 im…