fattening Samman Enhla bivariate • • air oftast control Regression -0 Huvudantagande " mer ✗ = C (* , AX + , ) U , = + u 0 problemet : y ✗ = conditional good as → precision " Xz makes ☒ , Y : er causalitet kroivs Vid selection • regression P + X, , mean Pz Xz + u independence randomized as + " " E -0 /u/ × , , ) Xz kontrollera for Xz giir , E = × , ( ) Xz) U random RCT =ʰ eftersom • → niojligt att skatta regression antagande starlet • randomiserat Sample 200,300 size randomiserat inte annars , IV • ( ◦ ↳ (2 , U ) C. X =D Za restriction : 2) =/ 0 Randomiserat . fair inte Instrumentet form skatta reduced , instrument relevance , Exclusion 2. b. , restriction fettermen 2 correlerad med Exclusion ↳ ( Instrument diir ha effektpa outcome noir detta inte that/er oftast utfall ej hitter DD Potential outcome E( Yo / ↳ : 1- = 1 A- l - , ) trends Parallel - E / Yo / 1- = 1, A- O - ) = E( Yo / 1- = 0 , A--1 ) - E / Yo / T -0 - A- O - , ) assumption Panel data ✗ ✗ = it + P , ✗ it + Uit +×i± C , / ✗ it , his / = 0 for alla s . t strict exogeneity vid brytpunkten Individual dummies RD ✗ Griinsviirdetniir ↳ tim ✗ ↑ Xo Elyot ×) = T running variable gcirmot Iim ✗ to Xo Xo E(Yolx) = noir X goir her motto " randomiserade "