Question

An article In the Journal of Environmentas Engineening (vol. 115, No. 3, 1989, pp. 608-619) reported the results of a study on the occurrence of sodlum and chlorlde in surface streams In central Rhode Island. The following data are chloride concentration y (in milligrams per liter) and roadway area in the watershed X (in percentage). 44 6.6 9.7 10.6 10,8 10.9 1112143 14.7 1517.3 19.2 22.9 272 2.531.5 39.3 y 4.4 6.6 9.7 10.6 10.8 10.9 11'E 12.1 14.3 14.7 15 17.3 19.2 22.9 27.2 27.6 31.5 39.3 X 0.19 0.15 0.57 0.7 0.67 0.63 0.47 0.7 0.5 0.78 | 0.81 0.78 0.69 1.3 1.05 1.06 1.74 1.62 (a) Calculate the coefflclent of determination for this model. Round your answer to 3 declmal places. R2 =1 (b) Prepare a normal probability plot of the residuals from the least squares ㎜odel. Does the nor ality assu ption see The normallty assumption seems to be to be satisfied? the absolute tolerance is t/-0.002 Reserve Problems Chapter 11 Section 7 Problem 3 It is known that carbon monoxide has a great influence on health. The following data are the carbon monoxide concentration (x in milligrams per cubic meter) and allergic morbidity y) 8.47 9.59 8.46 9.45 6.22 9,33 6.26 5.65 4.38 3,54 6.29 14.6 16,4 16.9 16.3 13.5 15,8 16.1 14.7 10.4 11.4 13.1 (a) Fit the linear regression model by least squares, find the estimates of the slope and intercept. Round your answer to two declmal places (e.g. 93.76) Bo 8.51093 Round your answer to three decimal places (e.g. 98.765) 4.38 3.54 6.29 10.4 11.4 13.1 (a) Fit the linear regression model by least squares, find the estimates of the slope and intercept. Round your answer to two decimal places (e.g. 98.76) 8.51093 Round your answer to three decimal places (e.g. 98.765) -84575 (b) Find the value of R2 Round your answer to one decimal place (e.g. 98.7).

Answer 1

r EXCEL Mega Stat) output Regression Analysis 0.851 r 0.923 Std. Error 3.699 n 18 Dep. Var.y ANOVA table Source df 1 1,252.1357 91.52 5.07E-08 16 17 MS value Regression 1252.1357 Residual 218.9043 Total 1471.0400 13.6815 confidence interval Regression out vanables Intercept coefficients t (df:16) std. error 0.5604 1.9269 x 20.3938 2.1318 0.291 9.567 5.07E-08 158746 24.9129 p-value 95% lower 95% upper std. coeff 5246 4.6453 0.000 0.923 7749 3.5 The value of coefficient of determination is R0.851 The normality assumption seems to be satisfied

EXCEL Mega Stat) output: Regression Analysis 0.691 r 0.831 Std. Error 1.260 Dep. Var.y ANOVA table Source df 1 31.9834 20.13 MS value 0015 Regression 31.9834 Residual 4.2984 Total 46.2818 1.5887 10 Regression out vanables Intercept confidence interval coefficients t (df-9 95% lower-95% upper-std., coeff. 0.000 0.831 std. error p-value 8.5032 1.3837 6.145 0002 5.3732 11.6333 0.8458 0.1885 4.487 0015 0.4193 1.2722 8.50 月= 0.85 (b). The e value of coefficient of determination is R0.691