Useful IDEA Shortcuts on Mac OS X

IntelliJ is my excellent partner in programming and project review. I make up this list for daily referrence and share with community. Golden shortcut: CMD + Shift + A FIND Find action by name: CMD + Shift + A Find class or file by name: CMD + Shift + O Show the list of available intention actions: ALT + Enter Find text in the project or in the...

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R Packages You Should Put Under Your Pillow

R在统计分析、机器学习、以及绘图上有着丰富的功能,基础安装包里的函数能够满足基本的需求,如果需要更多样化、复杂的数据处理,可以试着使用以下工具: 数据清洗转换 (Data wangling) DescTools (Tools for describing data and descriptive statistics) dplyr (面向data.frame,plyr的下次迭代,让R具有流式数据处理的风格) plyr (有用的ddply函数,参考http://www.r-bloggers.com/a-fast-intro-to-plyr-for-r/) reshape (数据变形的基本操作,丰富但底层) reshape2 (功能强大的melt和cast数据融合函数,reshape简版...

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Inspiring GIS Projects in R

R is a free software for statistical computing and graphics (as declaimed in its project vision). But in my view, its horizon is beyond that thanking to its flexible extension infrastructure. As a PhD student leveraging data mining techniques in computer network measurement and analysis, I am even shocked by the community passion and creativity ...

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统计中的样本检验基础和R实践

本文总结了R in Action一书中提到的关于样本检验的内容,以概要的形式提供给读者以及自己参考。 注: H0表示空假设,即样本检测的假设对象。 独立性检验(列联表) 卡方检验:*H0:假设二维表的行和列变量相互独立。stats包的chisq.test() Fisher精确检验: *H0:边界固定的二维列联表行和列独立。stats包的fisher.test() Cochran-Mantel-Haenszel检验:*H0:两个名义变量在第三个变量的每一层中都是条件独立的。stats包的.test() 相关性检验 常用系数:Pearson, Spearman, Kendall, 偏相关系数, 多分格polychoric,多系列polyserial PSK: 相关系数cor()...

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