1、1Difference in Difference ModelsBill EvansSpring 20082Difference in difference models Maybe the most popular identification strategy in applied work today Attempts to mimic random assignment with treatment and “comparison” sample Application of two-way fixed effects model 3Problem set up Cross-sec...
双重差分模型differenceindifferencesmodels.ppt,Difference in Difference Models Bill Evans Spring 2008 Difference in difference models Maybe the most popular identification strategy in applied work today Attempts to mimic random assignment with treatment a
Key concept: can control for the fact that the intervention is more likely in some types of states 6 Three different presentations ? Tabular ? Graphical ? Regression equation 7 Difference in Difference Before Change Group 1 (Treat) Group 2 (Control) Difference Yt1 Yc1 After Change Yt2 Yc2 ...
双重差分模型幻灯片+-+difference+in+differences+models
Linearization of difference equation model, 视频播放量 478、弹幕量 0、点赞数 11、投硬币枚数 4、收藏人数 9、转发人数 2, 视频作者 董水水不划水, 作者简介 ,相关视频:Stochastic Model — Stochastic Differential Equations (SDE),NPDE - Finite Difference Metho
古埃及人相信他们死后会到死后世界去。他们认为身体是灵魂的容器,灵魂每天晚上会离开自己的身体,早上再回来1DifferenceinDifferenceModelsBillEvansSpr..
(Y c2 -Y c1 ) 9 KeyAssumption •Controlgroupidentifiesthetimepathof outcomesthatwouldhavehappenedin theabsenceofthetreatment •Inthisexample,YfallsbyY c2 -Y c1 even withouttheintervention •Notethatunderlying‘levels’ofoutcomes arenotimportant(returntothisinthe regressionequation) 10 time Y t ...
–Crosssectionandtimefixedeffects •Usetimeseriesofuntreatedgrouptoestablishwhatwouldhaveoccurredintheabsenceoftheintervention •Keyconcept:cancontrolforthefactthattheinterventionismorelikelyinsometypesofstates 6 Threedifferentpresentations •Tabular•Graphical•Regressionequation 7 DifferenceinDifference ...
•Basictwo-wayfixedeffectsmodel –Crosssectionandtimefixedeffects •Usetimeseriesofuntreatedgrouptoestablishwhatwouldhaveoccurredintheabsenceoftheintervention•Keyconcept:cancontrolforthefactthattheinterventionismorelikelyinsometypesofstates 6 Threedifferentpresentations •Tabular•Graphical•Regressionequation ...
Hence, in our example, the effect of afternoon lessons on student learning is identified by comparing the gains in average test scores over the school year between the two classes. Sign in to download full-size image Fig. 1.2. Stylized exposition of identification in the DiD model. The idea...