In a regression model y=β0+β1x+ϵy = \beta_0 + \beta_1x + \epsilony=β0+β1x+ϵ, what does the coefficient β1\beta_1β1 represent?
The value of yyy when x=0x=0x=0.
The change in yyy for a one-unit increase in xxx.
The variance of the error term.
The correlation coefficient.