SAT Scores Educational researchers desired to find out if a relationship exists between the average SAT verbal score and the average SAT mathematical score. Several states were randomly selected and their SAT average scores are recorded below. Verbal.x 585 526 589 503 594 606 517 530 589 588 Math y Send data to Excel

Predicting final exams How well do exams given duringthe semester predict performance on the final? One classhad three tests during the semester. Computer output ofthe regression givesDependent variable is Finals = 13.46 R-Sq = 77.7, R-Sq(adj) = 74.1,Predictor Coeff SE(Coeff) t-Ratio P-ValueIntercept -6.72 14.00 -0.48 0.636Test1 0.2560 0.2274 1.13 0.274Test2 0.3912 0.2198 1.78 0.091Test3 0.9015 0.2086 4.32 60.0001Analysis of VarianceSource DF SS MS F-Ratio P-ValueRegression 3 11961.8 3987.3 22.02 60.0001Error 19 3440.8 181.1Total 22 15402.6a) Write the equation of the regression model.b) How much of the variation in final exam scores isaccounted for by the regression model?c) Explain in context what the coefficient of Test3 scoresmeans.d) A student argues that clearly the first exam doesn’t helpto predict final performance. She suggests that this examnot be given at all. Does Test1 have no effect on the finalexam score? Can you tell from this model? (Hint: Doyou think test scores are…

What does the residual plot tell you about the linear regression model? * 20 10 -10 -20 20 30 40 50 60 70 Fitted Value The plot suggests that the residuals having a constant variance. The linear model could not be used for prediction. O we can conclude that there is significant relationship between the variables. O The linear model is appropriate to explain the relationship between the variables. Residual

Interperting Regression Results (Continuation of Exercise 8-39) The following table showsadditional regression results presented by the researchers in the study described in Exercise 8-39.There are two regressions. The right-hand column shows the results for all patients, including thosetreated with laparoscopic surgery. The left-hand column shows the results for the sample of patientswho were treated without the laparoscopic surgery.Nonlaparoscopic Patients Only All PatientsCoefficients for Independent VariablesRegression intercept $8,043 $3,719 Length of stay Coefficient* Not significant 861 Standard error for the coefficient Not applicable 80 Number of complications Coefficient 3,393 1,986 Standard error for the coefficient 1,239 406 Laparascopic Coefficient Not applicable 908 Standard error for the coefficient Not applicable 358 R-squared 0.11 0.53 *All independent variables are significant at the level of p = .05 (and t-value >2) except for the length of stay variable in the…