Two properties of r ①r2>0 ②0≤r2≤1 RSS ■ Computer2 ∑ 6.41) ∑ (6.42) ∑ The coefficient of Correlation ∑x1-x Xiyi (644) ∑∝1-x2∑-Y 2x2Σ (6.45) I (6.46) ■△ r has the same sign as the slope coefficient◼ Two properties of r 2 : ① r 2>0 ② 0≤r 2≤1 ◼ Compute r 2 : (6.41) (6.42) ◼ The coefficient of Correlation,r r= = （6.44） (6.45) r=± (6.46) ◼ △ r has the same sign as the slope coefficient  = +  = + 2 i 2 2 i 2 y e r TSS RSS 1 r   = − 2 i 2 2 i y e r 1    − − − − 2 i 2 i i i (X X) (Y Y) (X X)(Y Y)    2 i 2 i i i χ y χ y 2 r