文档介绍：1 Silver ’ s Gym: Student Coaching Slides Silver ’ s Gym: Student Coaching Slides 2 Question 1: Regression Analysis Question 1: Regression Analysis Y = a + bX, X is given, Y is predicted Y = a + bX, X is given, Y is predicted 3 Question 1: Excel Steps Question 1: Excel Steps ? Go to web site to get data ? Click Data, then Data Analysis on right (If not in menu, click Add-ins, Analysis Tool Pak) ? Regression, OK ? Click labels ? Enter two columns of numbers ? Note: dialog box has Y before X ? Go to web site to get data ? Click Data, then Data Analysis on right (If not in menu, click Add-ins, Analysis Tool Pak) ? Regression, OK ? Click labels ? Enter two columns of numbers ? Note: dialog box has Y before X 4 Question 1: Regression Equation Question 1: Regression Equation ? Bottom table, Column = Coefficients ? Row = intercept =a ? Row = cholesterol = b = slope ? Interpret slope: If X increases by 1 unit, Y changes (increases? decreases?) by b units ? Bottom table, Column = Coefficients ? Row = intercept =a ? Row = cholesterol = b = slope ? Interpret slope: If X increases by 1 unit, Y changes (increases? decreases?) by b units 5 Question 1: Coefficient of Determination Question 1: Coefficient of Determination ? Top table ? Row = R square ? Interpret: R-square per cent of total variation in Y is explained by variation in X ? Top table ? Row = R square ? Interpret: R-square per cent of total variation in Y is explained by variation in X 6 Questions 2: Expected Value Questions 2: Expected Value ? E(X) = Σ xP(x) ? Hint: Add constant value to E(x) to get total cost ? E(X) = Σ xP(x) ? Hint: Add constant value to E(x) to get total cost 7 Question 3: Find Mean Question 3: Find Mean ? Mean = age at which average person experiences incident = μ ? Normal: Z = (x- μ )/σ? Value of Z from normal table in statistics book ? Use algebra to solve for μ ? Mean = age at which average person experiences incident = μ ? Normal: Z = (x- μ )/σ? Value of Z from normal tabl