3780 1 15:34 App STATA|问题解答第四期,DID模型是否要加入post和treat,treat被omit?线性插值法什么时候用 3.1万 32 6:06 App 相关系数、回归系数符号不一致——如何处理? 1.7万 3 17:04 App 「Stata」一个视频搞懂固定效应!原理与推荐回归方法 浏览方式(推荐使用) 哔哩哔哩 你感兴趣的视频都在B站 打开信息...
time variable: year, 68 to 88, but with gaps delta: 1 unit 变量加工与描述性统计: xtdescribe g age2= age^2 g ttl_exp2=ttl_exp^2 g tenure2=tenure^2 global xlist "grade age age2 ttl_exp ttl_exp2 tenure tenure2 not_smsa south race" sum ln_w $xlist 2. 传统DID 在这个数据集中...
treat_post:基准回归的DID变量 asinhso2_i:这篇文章的因变量,企业硫排放的反双曲正弦 firm:企业代码 ind4_fe:行业代码 area2_fe:地区代码 此外,需要确保这是一个公司年面板数据结构 . xtset firm year Panel variable: firm (unbalanced) Time variable: year, 2004 to 2013, but with gaps Delta: 1 unit...
随机效应模型假设个体效应 uiui 与解释变量 XitXit 无关(E[ui∣Xit]=0E[ui∣Xit]=0)。这一假设在许多实际情况下可能不成立,例如某些未观测到的个体特征可能与解释变量相关联。如果忽略这种相关性,随机效应模型的估计会产生偏误。 如果采用固定效应模型进行估计,固定效应模型假设个体效应 uiui...
stata sdid outcome_variable group_variable time_variable treatment_variable, vce(bootstrap) covariates(covariate_list) 动态合成DID的灵活性使得这一方法在处理异质性干预效果方面展现了更为显著的优越性。 三、经典案例应用 为了更好地展示sdid的实际应用,以下提供了一个经典案例,基于提案99(Abadie et al., 20...
使用sdid进行估计,导出权重和趋势图: . sdid packspercapita state year treated, vce(placebo) seed(1213) graph g1_opt(xtitle("")) g2_ 可以使用 and 输出结果:eststoesttab *create a uniform variable to use as a control gen r=runiform ...
display “error: variable not found” display “{txt}the variable mpg has mean {res:21.3} in the sample” display “When using the {cmd:summarize} command, specify” display “{cmdab:su:mmarize}[{it:varlist}][{it:weight}][{cmdab:if} {it:exp}]” ...
regress gp100m weight foreing variable foreing not found r(111); . end of do-file The do "/tmp/. . . " command is how Stata executes the commands in the Do-file Editor. Stata saves the commands from a do-file with unsaved changes to a temporary file and issues the do ...
{text}the variable mpg has mean {result: 21.3} in the sample" display "{text}mpg {c |} {result}21.3" display "{text}mpg {c |} {result:21.3}" display "error: variable not found" display "{txt}the variable mpg has mean {res:21.3} in the sample" display "When using the {cmd:...
For example, we have no variable called y. Let us ask Mata to show us the contents of y : : y <istmt>: 3499 y not found r(3499); : _ In this case, what we typed made perfect sense—show me y—but y has never been defined. This ugly message is called an run-time error...