greater than I The Empirical Rule (the distribution is symmetric and bell-shaped) 7% 2基本概念和知识点 Chebyshev's Theorem,The Empirical Rule 3.问题与应用 (1)Apply Chebyshev's Theorem and the Empirical Rule Section7 Summarizing Grouped Data 1.主要内容 Sample Population Mean:r.∑以 Mean:F=∑mf N Variane:s-∑m-yi Varance:r=∑m-HPf n-1 N 2.基本概念和知识点 Grouped data 3.问题与应用 1.主要内容 The objective numerical measure that reveals the direction of the linear relationship between two variables Sample Covariance Population Covariance 与，=s-0,-刃 n- 0,=∑-40-4) Sample Correlation Coefficient Population Correlation Coefficient S Ps=Gy11 greater than 1 The Empirical Rule (the distribution is symmetric and bell-shaped) 2.基本概念和知识点 Chebyshev’s Theorem, The Empirical Rule 3.问题与应用 (1)Apply Chebyshev’s Theorem and the Empirical Rule Section7 Summarizing Grouped Data 1.主要内容 2 2 Sample Mean: ( ) Variance: 1 i i i i m f x n m x f s n = − = −   2 2 Population Mean: ( ) Variance: i i i i m f x N m f s N  = − =   2.基本概念和知识点 Grouped data 3.问题与应用 (1) Calculate the mean and variance for grouped data Section8. Covariance and Correlation 1.主要内容 The objective numerical measure that reveals the direction of the linear relationship between two variables Sample Covariance ( )( ) 1 i i xy x x y y s n − − = −  Population Covariance ( )( ) i x i y xy x y N    − − =  Sample Correlation Coefficient xy xy x y s r s s = Population Correlation Coefficient xy xy x y     =