Concept explainers
Let x and y be random variables of the continuous type having the joint
Draw a graph that illustrates the domain of this pdI.
(a) Find the marginal pdfs of X and Y.
(b) Compute
(c) Determine the equation of the least squares regression line and draw it on your graph. Does the line make sense to you intuitively?
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- Which pair of data points are always on the regression line: Y = a + bx? (0, 0) (0, b) (X, Y) (a,0)arrow_forwardA Perodua dealer has hired you to analyze automobile demand in 30 regional markets for MyVi Model. A regression analysis was conducted using the following model. Q, = a + b, P, + b, Y +b, P + b, A Where, Q, = quantity demanded per year of MyVi automobiles. P,= average price of MyVi automobiles in thousands, (RM40) Y = household income in thousands, (RM24) P= average price of Kia Rio automobiles in thousands, (RM45) A = advertising expenditures per year in thousands, (RM400) The results of the computer analysis based on data collected in 30 regional markets are shown below: Variable Coefficient Std Error t-statistics Intercept 2,000 1000 2.00 Pp -10 2.5 -4.00 Y 0.025 0.02 1.25 PM 1.5 3.33 А 0.0825 0.025 3.3 Coefficient of determination, R = 0.96 %3D Standard error of estimate, SEE = 5.0 c) Based on 95% confidence level, identify the independent variables which can significantly influence demand for MyVi (t 2s. a s005 = 2.06). d) Calculate the price elasticity of demand. Would a…arrow_forwardFind the least-squares regression line ŷ = bo + b1r through the points %3D (-1,2), (2, 6), (5, 13), (7, 20), (10, 23), and then use it to find point estimates y corresponding to x = 3 and x = 6. For = 3, y = %3D For I = 6, y = %3Darrow_forward
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- Elementary Linear Algebra (MindTap Course List)AlgebraISBN:9781305658004Author:Ron LarsonPublisher:Cengage Learning