Answers are given in blue. Please solve ONLY USING EXCEL
a] Using technology, censtruet a regression model using all three independent variables, where y: Cost, 31 =Age, x2 = Days, and x3 = ICU. A 1 ' 1 ' y: 435 +[113]}{1+(1218)}{2+ 2187K3 (Round to the nearest integer as needed.) b] Test the significance of each independent variable using 0:: 0.05. Identify the general form of the null and alternative hypotheses, where [3]- is the population regression coefficient forthejth independent variable. Find the p-value for the coefficient of each independent variable. Variable p-value X1 0.003 0.000 X3 0.062 (Round to three decimal places as needed. )Interpret the p-value for the hypothesis test corresponding to X1 . Since the p-value associated with x, is less than ( = 0.05, reject the null hypothesis. There is sufficient evidence to conclude that there is a relationship between x, and y. Interpret the p-value for the hypothesis test corresponding to x2. Since the p-value associated with *2 is less than a = 0.05, reject the null hypothesis. There is sufficient evidence to conclude that there is a relationship between x2 and y. Interpret the p-value for the hypothesis test corresponding to x3. Since the p-value associated with *; is greater than @=0.05, do not reject the null hypothesis. There is insufficient evidence to conclude that there is a relationship between x3 and y.c) Interpret the p-value for each independent variable. Choose the correct answer below. O A. According to the p-values, only the independent variable *; has a relationship with y. B. According to the p-values, only the independent variable x2 has a relationship with y. O C. According to the p-values, the independent variables x1 , *, and x have a relationship with y. D. According to the p-values, the independent variables x, and *, have a relationship with y.d] Construct a 95% confidence interval forthe regression coefficient forthe ICU variable x3, in terms of expected costs. . . . ' ' The 95% confidence interval is from 119 to 4.492 . (Round to the nearest integer as needed.) State the 95% confidence interval fer the regressmn CDefflCleht for the ICU variable In terms of expected EDStS Choose the correct answer below One can be 95% confident that a 1% increase in the average total hospital bill Will cause the bill to be between the lower confidence limit and the upper confidence limit. in dollars. if all other variables are held constant One can be 95% confident that the average total hospital bill will be between the lower confidence limit and the upper confidence limit. in dollars. if all othervariables are held constant. The confidence interval indicates the range of the average total hospital bill if the value of the ICU variable is D, with 95% confidence, if all other variables are held constant. One can be 95% confident that an extra 1 day stay in the hospital's ICU will change the average total hospital bill between the lower confidence limit and the upper confidence limit, in dollars, if all other variables are held constant. e) Using the results from part (d), comment on the significance of the x3 variable. Since the confidence interval includes 0, there is insufficient evidence to conclude that the true population coefficient, By , is not 0 and that there is a relationship between the number of days spent in the ICU and the total hospital bill
