R_codes

说明：  该书是一本较好的R语言编程书籍，从认识到实战，手把手教你如何使用R语言进行数据分析、挖掘、画图等等。(This book is a good R language programming book, from understanding to actual combat, teach you how to use R language data analysis, mining, drawing and so on.)

双重差分估计 双重差分模型（difference-in-difference，DID）近年来多用于计量经济学中对于公共政策或项目实施效果 的定量评估。 通常大范围的公共政策有别于普通科研性研究，难以保证对于政策实施组和对照组在样本分配上的完全随机。非随机分配政策实施组和对照组的试验称为自然试验（naturaltrial），此类试验存在较显著的特点，即不同组间样本在政策实施前可能存在事前差异，仅通过单一前后对比或横向对比的分析方法会忽略这种差异，继而导致对政策实施效果的有偏估计。(Quantitative evaluation of policy or project implementation effect. Generally, a wide range of public policies is different from general scientific research, and it is difficult to ensure that the sample allocation for the policy implementation group and the control group is completely random. The non-randomly assigned policy implementation group and the control group are called natural trials, which have significant characteristics, i.e. there may be prior differences between the different groups of samples before the implementation of the policy, and this difference will be ignored only through a single pre-and post-comparison or horizontal comparison analysis method, which leads to the policy. Biased estimation of implementation)

计算CVAR 条件下的最有权重，主要针对股票收益率进行分析(compute the optimal weight under CVAR condition)

说明：  《时间序列分析及应用：R语言，潘红宇》书籍分享(Time Series Analysis and Application: R Language, Pan Hongyu)

说明：  制作pcoa、饼图、venn图、热图、柱状图的脚本，可直接改参数使用，内有注释，适用于微生物多样性(the Script to make PCOA)

说明：  spei的R语言计算版本 用于计算干旱指数spei(R language computing version of spei)

《时间序列分析及应用：R语言，潘红宇》书籍分享(Time Series Analysis and Application: R Language, Pan Hongyu)

从GEO数据库下载原始数据，提取数据中的表达值(Download raw data from the GEO database and extract the expression values in the data)

在R中如何导入数据，主要是txt，csv，excel等数据格式的导入(how to imput data in R)

说明：  一篇论文的GARCH in mean VAR(GARCH in mean VAR of a published paper)