In a simple linear regression y=β0+β1x+ϵy = \beta_0 + \beta_1x + \epsilony=β0+β1x+ϵ, what does testing H0:β1=0H_0: \beta_1 = 0H0:β1=0 accomplish?
Testing if the intercept is zero.
Testing if there is a linear relationship between xxx and yyy.
Testing if the variance of residuals is constant.
Testing if the mean of yyy is zero.