The t Test(cont) Knowing the sampling distribution for the standardized estimator allows us to carry out hypothesis tests Start with a null hypothesis ◆For example,Ho:BO If accept null,then fail to reject that x,has no effect on y,controlling for other x's Econometrics 15-Zhuxi@SJTU 11Econometrics 15 - Zhuxi@SJTU 11 The t Test (cont) Knowing the sampling distribution for the standardized estimator allows us to carry out hypothesis tests Start with a null hypothesis For example, H0 : bj=0 If accept null, then fail to reject that xj has no effect on y, controlling for other x’s