Help with all expect question 2 & 3
Questions 1 - 3
| PRINCIPLES OF STATISTICS II | SPRING 2018 | |||||||||||||||||||
| ECON 262 | ||||||||||||||||||||
| FINAL EXAM | ||||||||||||||||||||
| You need to send back your answers (Excel files, PDF, Word files) in Canvas that clearly present your detailed answers. | ||||||||||||||||||||
| Since this is a take home exam, I expect a lot of detail in the answers and will set a high bar for grading (higher than Exam One). Review the answers | ||||||||||||||||||||
| to the problem sets, and Exam One posted in Canvas to get a feel for what I expect. | ||||||||||||||||||||
| ONE WORD ANSWERS WITHOUT ANALYTICAL SUPPORT WILL NOT BE SUFFICIENT TO SCORE WELL ON THIS EXAM. | ||||||||||||||||||||
| Due Date: Friday May 11, 2018 at 11:55 p.m. Test answers submitted late will receive a grade of zero. | ||||||||||||||||||||
| There are six questions located in the four workbooks. | ||||||||||||||||||||
| Make good use of the Lecture Notes, textbook and answers to the Problem Sets and Exam One. | ||||||||||||||||||||
| 100 Points Total | ||||||||||||||||||||
| (20) | 1. | A retail store manager with Petrie Stores, Inc, wants to develop a multiple regression model to predict | ||||||||||||||||||
| the amount of sales of a product per month Y from monthly advertising expenditures X1 and | ||||||||||||||||||||
| whether the month was December (coded 1) or another month (coded 0) X2. The multiple regression | Advertising | |||||||||||||||||||
| results are presented below. | Expenditures (X1) | Sales (Y) | ||||||||||||||||||
| ($) | ($) | |||||||||||||||||||
| SUMMARY OUTPUT | 2,200 | 14,800 | ||||||||||||||||||
| 3,000 | 17,300 | |||||||||||||||||||
| Regression Statistics | 2,400 | 8,200 | ||||||||||||||||||
| Multiple R | 0.8281456316444125 | 2,000 | 12,300 | |||||||||||||||||
| R Square | 0.6858251872117229 | 2,100 | 11,200 | |||||||||||||||||
| Adjusted R Square | 0.6488634445307494 | 2,400 | 16,000 | |||||||||||||||||
| Standard Error | 1779.2905623921506 | 2,700 | 11,100 | |||||||||||||||||
| Observations | 20.0 | 2,200 | 10,000 | |||||||||||||||||
| 1,100 | 14,500 | |||||||||||||||||||
| ANOVA | 2,100 | 11,900 | ||||||||||||||||||
| df | SS | MS | F | 2,400 | 14,400 | |||||||||||||||
| Regression | 2.0 | 1.174856266078978E8 | 5.87428133039489E7 | 1,300 | 5,800 | |||||||||||||||
| Residual | 17.0 | 5.38198733921022E7 | 3165874.905417776 | 1,300 | 12,200 | |||||||||||||||
| Total | 19.0 | 1.713055E8 | 2,000 | 15,300 | ||||||||||||||||
| 2,000 | 12,600 | |||||||||||||||||||
| Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | 1,300 | 12,000 | |||||||||||||
| Intercept | 4081.80939102274 | 1840.5557922459727 | 2.2177047869012627 | 0.040487672121620646 | 198.57068547602088 | 7965.048096569459 | 2,000 | 9,600 | ||||||||||||
| X Variable 1 | 2.599149950526228 | 0.8049034203187287 | 0.004928420748804941 | 0.9009498040397608 | 4.297350097012695 | 2,200 | 11,400 | |||||||||||||
| X Variable 2 | 4503.013402896468 | 836.3099302978545 | 4.943117857197039E-5 | 2738.5512198714296 | 6267.475585921506 | 2,100 | 10,100 | |||||||||||||
| 2,800 | 17,600 | |||||||||||||||||||
| (a) | Construct a scatterplot between sales (Y) and advertising expenditures (X1). See data to the right. | |||||||||||||||||||
| Provide a standard evaluation of the scatterplot. | ||||||||||||||||||||
| (b) | Which of the explanatory variables (if any) are statistically significant (at the .05 level) in explaining product | |||||||||||||||||||
| sales per month? Conduct a formal hypothesis test for each estimated regression coefficient. | ||||||||||||||||||||
| (c) | Give an interpretation (as applicable to the data) for each of the estimated regression coefficients. | |||||||||||||||||||
| (d) | How much of the variation of y around ybar can be explained by the regression model? | |||||||||||||||||||
| (e) | Calculate the F-Statistic | |||||||||||||||||||
| (f) | Conduct an F-Test (.05 level) to test for a globally statistically significant regression equation. | |||||||||||||||||||
| (g) | Find the predicted sales per month when advertising expenditures equal $2,000 and the month is July. | |||||||||||||||||||
| (g) | Find the predicted sales per month when advertising expenditures equal $2,000 and the month is December. | |||||||||||||||||||
| (i) | Provide a brief evaluation of the estimated regression equation. Would the equation be suitable for forecasting? | |||||||||||||||||||
| All calculations for Questions 2 & 3 should be performed by hand (pencil/pen and paper or by Hand in Excel = layout all the calculations). | ||||||||||||||||||||
| The only exception is the scatterplot which can be constructed using Excel. | ||||||||||||||||||||
| (10) | 2. | A sociologist was hired by a large city hospital to investigate the relationship between the number of | ||||||||||||||||||
| unauthorized days that employees are absent per year Y, and the distance (miles) X1 between home | ||||||||||||||||||||
| and work for the employees. A sample of 5 employees was chosen, and the following data were collected. | ||||||||||||||||||||
| Distance to | Number of | |||||||||||||||||||
| Work | Days Absent | |||||||||||||||||||
| (X1) | (Y) | |||||||||||||||||||
| 1.0 | 8.0 | |||||||||||||||||||
| 3.0 | 5.0 | |||||||||||||||||||
| 8.0 | 6.0 | |||||||||||||||||||
| 12.0 | 5.0 | |||||||||||||||||||
| 18.0 | 2.0 | |||||||||||||||||||
| (a) | Construct a scatterplot using Excel. Provide a standard evaluation of the scatterplot. | |||||||||||||||||||
| (b) | Estimate the slope coefficient and intercept term for the regression line that relates number | |||||||||||||||||||
| of absent days to distance to work by hand. Express the estimated equation in standard form. | ||||||||||||||||||||
| (c) | Interpret (as applicable to the data) the estimated slope coefficient and intercept term. | |||||||||||||||||||
| (d) | Compute the Errors, Sum of Squared Errors (SSE), Mean Square Error (MSE) and Regression Standard Error (SE). | |||||||||||||||||||
| (10) | 3. | Based on the estimated regression equation in Question Two and the calculated SSE, MSE & SE, does a | ||||||||||||||||||
| statistically significant (.05 level) relationship exist between the number of days absent | ||||||||||||||||||||
| and the distance to work? Hint: Perform a hypothesis test on the slope coefficient. | ||||||||||||||||||||
| HAVE FUN WITH THIS EXAM |
Question 4
| PRINCIPLES OF STATISTICS II | SPRING 2018 | |||||||
| ECON 262 | ||||||||
| FINAL EXAM | ||||||||
| On the Computer | ||||||||
| (20) | 4. The following data reports annual wages (Y) for a sample of 100 workers. Also included are explanatory variables | |||||||
| relating to years of experience of the workers (X1), age of the workers (X2), years of education (X3) and whether or not | ||||||||
| the worker is a union member (X4, 0 = non union member, 1 = union member) | ||||||||
| 1) Conduct a full regression analysis of this data set. Determine the "Best" equation to predict wages (Y) based on the potential explanatory variables. | ||||||||
| Your analysis should include (but not limited to) scatterplots and evaluations, simple regressions and evaluations that should include hypothesis tests on the slope coefficients, | ||||||||
| interpretations of the Rsquare, multiple regression analysis and hypothesis tests on the slope coefficients, Global F-Test, drop insignificant variables, re-estimated equations and re-evaluation | ||||||||
| until you find the best regression equation to predict annual wages (Y). Use a .05 significance level for hypothesis tests related to individual coefficients (t-tests) and Global F-Tests. | ||||||||
| 2) Based on you "Best" equation to predict wages (Y) in part 1, predict wages (y) based on the available forecasts of the potential explanatory variables at the bottom of the data set. | ||||||||
| Provide all estimated regression equations and scatterplots to support your analysis and answers. | ||||||||
| This question and answers will test your knowledge on how to conduct a full regression analysis on a dataset. | ||||||||
| Wage (Y) | Experience (X1) | Age (X2) | Education (X3) | Union (X4) 0 = no union 1 = union | ||||
| $19,388 | 45 | 57 | 6 | 0 | ||||
| $49,898 | 33 | 51 | 12 | 1 | ||||
| $28,219 | 12 | 30 | 12 | 0 | ||||
| $83,601 | 18 | 41 | 17 | 0 | ||||
| $29,736 | 47 | 61 | 8 | 1 | ||||
| $50,235 | 12 | 34 | 16 | 0 | ||||
| $45,976 | 43 | 61 | 12 | 1 | ||||
| $33,411 | 20 | 38 | 12 | 0 | ||||
| $21,716 | 11 | 29 | 12 | 0 | ||||
| $37,664 | 19 | 43 | 18 | 0 | ||||
| $26,820 | 33 | 57 | 18 | 1 | ||||
| $29,977 | 6 | 28 | 16 | 0 | ||||
| $33,959 | 26 | 49 | 17 | 1 | ||||
| $11,780 | 33 | 50 | 11 | 0 | ||||
| $10,997 | 0 | 20 | 14 | 0 | ||||
| $17,626 | 45 | 63 | 12 | 0 | ||||
| $22,133 | 10 | 32 | 16 | 1 | ||||
| $21,994 | 24 | 42 | 12 | 0 | ||||
| $29,390 | 18 | 37 | 13 | 0 | ||||
| $32,138 | 22 | 42 | 14 | 1 | ||||
| $30,006 | 27 | 49 | 16 | 0 | ||||
| $68,573 | 14 | 36 | 16 | 1 | ||||
| $17,694 | 38 | 52 | 8 | 0 | ||||
| $26,795 | 44 | 57 | 7 | 0 | ||||
| $19,981 | 54 | 64 | 4 | 0 | ||||
| $14,476 | 3 | 21 | 12 | 0 | ||||
| $19,452 | 3 | 22 | 13 | 0 | ||||
| $28,168 | 17 | 36 | 13 | 0 | ||||
| $19,306 | 34 | 49 | 9 | 1 | ||||
| $13,318 | 25 | 42 | 11 | 1 | ||||
| $25,166 | 10 | 28 | 12 | 0 | ||||
| $18,121 | 18 | 36 | 12 | 0 | ||||
| $13,162 | 6 | 24 | 12 | 1 | ||||
| $32,094 | 14 | 32 | 12 | 0 | ||||
| $16,667 | 4 | 22 | 12 | 0 | ||||
| $50,171 | 39 | 57 | 12 | 1 | ||||
| $31,691 | 13 | 31 | 12 | 0 | ||||
| $36,178 | 40 | 58 | 12 | 0 | ||||
| $15,234 | 4 | 22 | 12 | 0 | ||||
| $16,817 | 26 | 44 | 12 | 0 | ||||
| $22,485 | 22 | 40 | 12 | 0 | ||||
| $30,308 | 10 | 28 | 12 | 0 | ||||
| $11,702 | 6 | 26 | 14 | 0 | ||||
| $11,186 | 0 | 18 | 12 | 0 | ||||
| $12,285 | 42 | 60 | 12 | 0 | ||||
| $19,284 | 3 | 25 | 16 | 0 | ||||
| $11,451 | 8 | 26 | 12 | 0 | ||||
| $57,623 | 31 | 52 | 15 | 0 | ||||
| $25,670 | 8 | 27 | 13 | 1 | ||||
| $83,443 | 5 | 28 | 17 | 0 | ||||
| $49,974 | 26 | 48 | 16 | 1 | ||||
| $46,646 | 44 | 55 | 5 | 0 | ||||
| $31,702 | 39 | 57 | 12 | 0 | ||||
| $13,312 | 9 | 27 | 12 | 0 | ||||
| $44,543 | 10 | 34 | 18 | 0 | ||||
| $15,013 | 21 | 43 | 16 | 0 | ||||
| $33,389 | 22 | 42 | 14 | 0 | ||||
| $60,626 | 7 | 31 | 18 | 0 | ||||
| $24,509 | 15 | 35 | 14 | 0 | ||||
| $20,852 | 38 | 56 | 12 | 0 | ||||
| $30,133 | 27 | 43 | 10 | 0 | ||||
| $31,799 | 25 | 43 | 12 | 0 | ||||
| $16,796 | 14 | 32 | 12 | 0 | ||||
| $20,793 | 6 | 24 | 12 | 0 | ||||
| $29,407 | 19 | 35 | 10 | 0 | ||||
| $29,191 | 9 | 27 | 12 | 0 | ||||
| $15,957 | 10 | 28 | 12 | 0 | ||||
| $34,484 | 28 | 47 | 13 | 0 | ||||
| $35,185 | 12 | 32 | 14 | 0 | ||||
| $26,614 | 19 | 37 | 12 | 0 | ||||
| $41,780 | 9 | 27 | 12 | 0 | ||||
| $55,777 | 21 | 41 | 14 | 0 | ||||
| $15,160 | 45 | 59 | 8 | 0 | ||||
| $66,738 | 29 | 44 | 9 | 0 | ||||
| $33,351 | 4 | 26 | 16 | 0 | ||||
| $33,498 | 20 | 36 | 10 | 0 | ||||
| $29,809 | 29 | 43 | 8 | 0 | ||||
| $15,193 | 15 | 33 | 12 | 0 | ||||
| $23,027 | 34 | 54 | 14 | 1 | ||||
| $75,165 | 12 | 33 | 15 | 0 | ||||
| $18,752 | 45 | 62 | 11 | 1 | ||||
| $83,569 | 29 | 53 | 18 | 0 | ||||
| $32,235 | 38 | 56 | 12 | 0 | ||||
| $20,852 | 1 | 19 | 12 | 0 | ||||
| $13,787 | 4 | 21 | 11 | 0 | ||||
| $34,746 | 15 | 35 | 14 | 0 | ||||
| $17,690 | 14 | 32 | 12 | 0 | ||||
| $52,762 | 7 | 31 | 18 | 0 | ||||
| $60,152 | 38 | 60 | 16 | 0 | ||||
| $33,461 | 7 | 29 | 16 | 1 | ||||
| $13,481 | 7 | 25 | 12 | 0 | ||||
| $9,879 | 28 | 46 | 12 | 0 | ||||
| $16,789 | 6 | 25 | 13 | 0 | ||||
| $31,304 | 26 | 48 | 16 | 0 | ||||
| $37,771 | 5 | 26 | 15 | 0 | ||||
| $50,187 | 24 | 42 | 12 | 0 | ||||
| $39,888 | 5 | 23 | 12 | 0 | ||||
| $19,227 | 15 | 33 | 12 | 0 | ||||
| $32,786 | 37 | 54 | 11 | 1 | ||||
| $28,440 | 24 | 42 | 12 | 0 | ||||
| Forecast Variables | 15 | 33 | 14 | 1 |
Question 5
| PRINCIPLES OF STATISTICS II | SPRING 2018 | |||||||||||||
| ECON 262 | ||||||||||||||
| FINAL EXAM | ||||||||||||||
| On the Computer | ||||||||||||||
| (20) | 5. Oklahoma Land & Agronomics, Inc., is interested in increasing crop production | |||||||||||||
| and has installed a center-pivot, mobile sprinkling system to water an alfalfa crop. | ||||||||||||||
| Oklahoma has collected data for the weekly growth of alfalfa Y (in inches) and for | ||||||||||||||
| the water flow setting X1 on the mobile sprinkling system (higher settings apply greater | ||||||||||||||
| amounts of water). Other conditions are held constant. | ||||||||||||||
| Water Flow | ||||||||||||||
| Growth | Setting | |||||||||||||
| (Y) | (X1) | |||||||||||||
| 1.6 | 0.0 | |||||||||||||
| 2.9 | 0.3 | |||||||||||||
| 3.7 | 0.6 | |||||||||||||
| 3.2 | 0.9 | |||||||||||||
| 3.5 | 1.3 | |||||||||||||
| 4.2 | 1.6 | |||||||||||||
| 5.3 | 1.9 | |||||||||||||
| 5.5 | 2.2 | |||||||||||||
| 6.2 | 2.5 | |||||||||||||
| 6.3 | 2.8 | |||||||||||||
| 6.2 | 3.2 | |||||||||||||
| 6.3 | 3.5 | |||||||||||||
| 6.5 | 3.8 | |||||||||||||
| 7.1 | 4.1 | |||||||||||||
| 7.6 | 4.4 | |||||||||||||
| 6.7 | 4.7 | |||||||||||||
| 6.9 | 5.1 | |||||||||||||
| 6.4 | 5.4 | |||||||||||||
| 6.7 | 5.7 | |||||||||||||
| 6.5 | 6.0 | |||||||||||||
| (a) Construct a scattergram between growth (Y) and water flow setting (x). | ||||||||||||||
| Does there appear to be a curvilinear relationship? Evaluate the scatterplot. | ||||||||||||||
| (b) Estimate a simple linear regression equation that could be used to predict growth. | ||||||||||||||
| Evaluate the estimated regression equation conducting all necessary statistical tests (.05 level). | ||||||||||||||
| (c) Create a second explanatory variable (X2) to reflect the quardratic (non-linear) shape to the scatterplot. | ||||||||||||||
| (d) Estimate a curvilinear multiple regression equation by including both the X1 and X2 explanatory | ||||||||||||||
| variables in the model. Evaluate the estimated regression equation conducting all necessary statistical tests (.05 level). | ||||||||||||||
| (e) Which estimated regression equation provides a better fit to the data? Justify your answer. | ||||||||||||||
| (f) Calculate the amount of water flow setting that will maximize growth. | ||||||||||||||
| (g) What will growth equal at the maximizing point calculated in part f? | ||||||||||||||
| (h) Based on your Best regression equation in part e, forecast growth at a water setting of of 1.8? | ||||||||||||||
| Provide all estimated regression equations and scatterplots to support your analysis and answers. | ||||||||||||||
| You need to email me back your answers (Excel files, PDF, Word files) in Canvas that clearly present your detailed answers. | ||||||||||||||
| Since this is a take home exam, I expect a lot of detail in the answers and will set a high bar for grading. | ||||||||||||||
| Due Date: Friday May 11, 2018 at 11:55 p.m. Test answers submitted late will receive a grade of zero. | ||||||||||||||
| There are five questions located in the three workbooks. | ||||||||||||||
| Questions 2 & 3 are to be done by hand (except scatterplots). Show all work. | ||||||||||||||
| Make good use of the Lecture Notes, textbook and answers to the Problem Sets. | ||||||||||||||
Question 6
| (20) | 6. | Salsberry Realty sells homes along the east coast of the United States. One of the questions | |||||||||||||||||||||||||
| most frequently asked is "If we buy a home, home much can we expect to pay to heat in | |||||||||||||||||||||||||||
| the winter? | |||||||||||||||||||||||||||
| To investigate, two scatterplots, two simple linear regressions, and one multiple linear regression were estimated, utilizing | |||||||||||||||||||||||||||
| variables thought to be related to January heating costs. A random sample of 20 recently | Y | temp | Age of Furnace | ||||||||||||||||||||||||
| sold homes was taken to collect the data for the regression analysis. The estimated simple | 250.0 | 35.0 | 3.0 | 35.0 | 250.0 | 3.0 | 250.0 | ||||||||||||||||||||
| and multiple linear regressions are presented below: | 360.0 | 29.0 | 4.0 | 29.0 | 360.0 | 4.0 | 360.0 | ||||||||||||||||||||
| 165.0 | 36.0 | 7.0 | 36.0 | 165.0 | 7.0 | 165.0 | |||||||||||||||||||||
| Simple Linear Regression One: | 43.0 | 60.0 | 6.0 | 60.0 | 43.0 | 6.0 | 43.0 | ||||||||||||||||||||
| Y= January Heating Costs ($) | 92.0 | 65.0 | 5.0 | 65.0 | 92.0 | 5.0 | 92.0 | ||||||||||||||||||||
| X = Mean January Outside Temperature (Degrees F) | 200.0 | 30.0 | 5.0 | 30.0 | 200.0 | 5.0 | 200.0 | ||||||||||||||||||||
| 355.0 | 10.0 | 6.0 | 10.0 | 355.0 | 6.0 | 355.0 | |||||||||||||||||||||
| SUMMARY OUTPUT | 290.0 | 7.0 | 10.0 | 7.0 | 290.0 | 10.0 | 290.0 | ||||||||||||||||||||
| Regression Statistics | 230.0 | 21.0 | 9.0 | 21.0 | 230.0 | 9.0 | 230.0 | ||||||||||||||||||||
| Multiple R | 0.8115088354934338 | 120.0 | 55.0 | 2.0 | 55.0 | 120.0 | 2.0 | 120.0 | |||||||||||||||||||
| R Square | 0.6585465900839089 | 73.0 | 54.0 | 12.0 | 54.0 | 73.0 | 12.0 | 73.0 | |||||||||||||||||||
| Adjusted R Square | 0.6395769561996816 | 205.0 | 48.0 | 5.0 | 48.0 | 205.0 | 5.0 | 205.0 | |||||||||||||||||||
| Standard Error | 63.55260675759623 | ``` | 400.0 | 20.0 | 5.0 | 20.0 | 400.0 | 5.0 | 400.0 | ||||||||||||||||||
| Observations | 20.0 | 320.0 | 39.0 | 4.0 | 39.0 | 320.0 | 4.0 | 320.0 | |||||||||||||||||||
| 72.0 | 60.0 | 8.0 | 60.0 | 72.0 | 8.0 | 72.0 | |||||||||||||||||||||
| ANOVA | 272.0 | 20.0 | 5.0 | 20.0 | 272.0 | 5.0 | 272.0 | ||||||||||||||||||||
| df | SS | MS | F | Significance F | 94.0 | 58.0 | 7.0 | 58.0 | 94.0 | 7.0 | 94.0 | ||||||||||||||||
| Regression | 1.0 | 140214.94113765802 | 140214.94113765802 | 34.715830263412286 | 1.4070071114966298E-5 | 190.0 | 40.0 | 8.0 | 40.0 | 190.0 | 8.0 | 190.0 | |||||||||||||||
| Residual | 18.0 | 72700.80886234199 | 4038.9338256856663 | 235.0 | 27.0 | 9.0 | 27.0 | 235.0 | 9.0 | 235.0 | |||||||||||||||||
| Total | 19.0 | 212915.75 | 139.0 | 30.0 | 7.0 | 30.0 | 139.0 | 7.0 | 139.0 | ||||||||||||||||||
| Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | Lower 95.0% | Upper 95.0% | ||||||||||||||||||||
| Intercept | 388.8019516599528 | 34.240843053207534 | 11.35491760689962 | 1.2218404739566874E-9 | 316.864609928764 | 460.7392933911416 | 316.864609928764 | 460.7392933911416 | |||||||||||||||||||
| X Variable 1 | -4.934192248923462 | 0.8374372765317352 | -5.89201410923398 | 1.4070071114966295E-5 | -6.693582677677995 | -3.1748018201689288 | -6.693582677677995 | -3.1748018201689288 | |||||||||||||||||||
| RESIDUAL OUTPUT | |||||||||||||||||||||||||||
| Observation | Predicted Y | Residuals | Standard Residuals | ||||||||||||||||||||||||
| 1.0 | 216.10522294763163 | 33.89477705236837 | 0.5479487754296747 | ||||||||||||||||||||||||
| 2.0 | 245.71037644117243 | 114.28962355882757 | 1.8476256438158871 | ||||||||||||||||||||||||
| 3.0 | 211.1710306987082 | -46.17103069870819 | -0.7464087960394269 | ||||||||||||||||||||||||
| 4.0 | 92.75041672454512 | -49.75041672454512 | -0.804273764043705 | ||||||||||||||||||||||||
| 5.0 | 68.07945547992779 | 23.920544520072212 | 0.38670362271843667 | ||||||||||||||||||||||||
| 6.0 | 240.77618419224896 | -40.77618419224896 | -0.659194782733538 | ||||||||||||||||||||||||
| 7.0 | 339.4600291707182 | 15.539970829281799 | 0.2512218319938128 | ||||||||||||||||||||||||
| 8.0 | 354.2626059174886 | -64.2626059174886 | -1.0388803019415993 | ||||||||||||||||||||||||
| 9.0 | 285.18391443256013 | -55.18391443256013 | -0.892112619298802 | ||||||||||||||||||||||||
| 10.0 | 117.42137796916239 | 2.5786220308376073 | 0.04168644572909851 | ||||||||||||||||||||||||
| 11.0 | 122.35557021808586 | -49.35557021808586 | -0.7978906077431704 | ||||||||||||||||||||||||
| 12.0 | 151.96072371162666 | 53.039276288373344 | 0.8574420314666036 | ||||||||||||||||||||||||
| 13.0 | 290.1181066814836 | 109.8818933185164 | 1.7763695212613329 | ||||||||||||||||||||||||
| 14.0 | 196.3684539519378 | 123.6315460480622 | 1.9986487639923738 | ||||||||||||||||||||||||
| 15.0 | 92.75041672454512 | -20.75041672454512 | -0.3354547934126464 | ||||||||||||||||||||||||
| 16.0 | 290.1181066814836 | -18.118106681483596 | -0.29290041807575323 | ||||||||||||||||||||||||
| 17.0 | 102.61880122239205 | -8.618801222392051 | -0.13933301783295002 | ||||||||||||||||||||||||
| 18.0 | 191.43426170301433 | -1.4342617030143288 | -0.02318652052492161 | ||||||||||||||||||||||||
| 19.0 | 255.57876093901933 | -20.578760939019332 | -0.33267977656185105 | ||||||||||||||||||||||||
| 20.0 | 240.77618419224896 | -101.77618419224896 | -1.645331238198868 | ||||||||||||||||||||||||
| 6. Continued | |||||||||||||||||||||||||||
| Simple Linear Regression Two: | |||||||||||||||||||||||||||
| Y= January Heating Costs ($) | |||||||||||||||||||||||||||
| X = Age of Furnace | |||||||||||||||||||||||||||
| ``` | |||||||||||||||||||||||||||
| SUMMARY OUTPUT | |||||||||||||||||||||||||||
| Regression Statistics | |||||||||||||||||||||||||||
| Multiple R | 0.25710133474306734 | ||||||||||||||||||||||||||
| R Square | 0.06610109632666676 | ||||||||||||||||||||||||||
| Adjusted R Square | 0.01421782390037047 | ||||||||||||||||||||||||||
| Standard Error | 105.10359585237413 | ||||||||||||||||||||||||||
| Observations | 20.0 | ||||||||||||||||||||||||||
| ANOVA | |||||||||||||||||||||||||||
| df | SS | MS | F | Significance F | |||||||||||||||||||||||
| Regression | 1.0 | 14073.964500214497 | 14073.964500214497 | 1.2740348331067175 | 0.2738307062372321 | ||||||||||||||||||||||
| Residual | 18.0 | 198841.7854997855 | 11046.765861099195 | ||||||||||||||||||||||||
| Total | 19.0 | 212915.75 | |||||||||||||||||||||||||
| Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | Lower 95.0% | Upper 95.0% | ||||||||||||||||||||
| Intercept | 275.02917202917206 | 66.13742595445467 | 4.158449895201093 | 5.902807638291656E-4 | 136.0795961566486 | 413.97874790169556 | 136.0795961566486 | 413.97874790169556 | |||||||||||||||||||
| X Variable 1 | -10.988845988845991 | 9.735571162986636 | -1.1287315150675639 | 0.2738307062372315 | -31.442522019499688 | 9.464830041807705 | -31.442522019499688 | 9.464830041807705 | |||||||||||||||||||
| RESIDUAL OUTPUT | |||||||||||||||||||||||||||
| Observation | Predicted Y | Residuals | Standard Residuals | ||||||||||||||||||||||||
| 1.0 | 242.0626340626341 | 7.937365937365911 | 0.07758886099341475 | ||||||||||||||||||||||||
| 2.0 | 231.07378807378808 | 128.92621192621192 | 1.2602717342864573 | ||||||||||||||||||||||||
| 3.0 | 198.10725010725014 | -33.10725010725014 | -0.3236279953218475 | ||||||||||||||||||||||||
| 4.0 | 209.09609609609612 | -166.09609609609612 | -1.6236125451746024 | ||||||||||||||||||||||||
| 5.0 | 220.0849420849421 | -128.0849420849421 | -1.2520482040514511 | ||||||||||||||||||||||||
| 6.0 | 220.0849420849421 | -20.0849420849421 | -0.19633311501403666 | ||||||||||||||||||||||||
| 7.0 | 209.09609609609612 | 145.90390390390388 | 1.426231045377928 | ||||||||||||||||||||||||
| 8.0 | 165.14071214071214 | 124.85928785928786 | 1.220516983328854 | ||||||||||||||||||||||||
| 9.0 | 176.12955812955812 | 53.87044187044188 | 0.5265910957012816 | ||||||||||||||||||||||||
| 10.0 | 253.05148005148007 | -133.05148005148007 | -1.3005968065658153 | ||||||||||||||||||||||||
| 11.0 | 143.16302016302018 | -70.16302016302018 | -0.6858533248012663 | ||||||||||||||||||||||||
| 12.0 | 220.0849420849421 | -15.0849420849421 | -0.14745741644748972 | ||||||||||||||||||||||||
| 13.0 | 220.0849420849421 | 179.9150579150579 | 1.758694827647842 | ||||||||||||||||||||||||
| 14.0 | 231.07378807378808 | 88.92621192621192 | 0.8692661457540816 | ||||||||||||||||||||||||
| 15.0 | 187.11840411840413 | -115.11840411840413 | -1.1252984838306117 | ||||||||||||||||||||||||
| 16.0 | 220.0849420849421 | 51.9150579150579 | 0.5074769443442396 | ||||||||||||||||||||||||
| 17.0 | 198.10725010725014 | -104.10725010725014 | -1.0176629149668144 | ||||||||||||||||||||||||
| 18.0 | 187.11840411840413 | 2.881595881595871 | 0.028168002339896588 | ||||||||||||||||||||||||
| 19.0 | 176.12955812955812 | 58.87044187044188 | 0.5754667942678285 | ||||||||||||||||||||||||
| 20.0 | 198.10725010725014 | -59.10725010725014 | -0.5777816278678917 | ||||||||||||||||||||||||
| 6. Continued | |||||||||||||||||||||||||||
| Multiple Linear Regression One: | |||||||||||||||||||||||||||
| Y= January Heating Costs ($) | |||||||||||||||||||||||||||
| X1 = Mean January Outside Temperature (Degrees F) | |||||||||||||||||||||||||||
| X2 = Age of Furnace | |||||||||||||||||||||||||||
| SUMMARY OUTPUT | |||||||||||||||||||||||||||
| Regression Statistics | |||||||||||||||||||||||||||
| Multiple R | 0.8808337071918113 | ||||||||||||||||||||||||||
| R Square | 0.7758680197252695 | ||||||||||||||||||||||||||
| Adjusted R Square | 0.7494995514576541 | ||||||||||||||||||||||||||
| Standard Error | 52.98236592277907 | ||||||||||||||||||||||||||
| Observations | 20.0 | ||||||||||||||||||||||||||
| ANOVA | |||||||||||||||||||||||||||
| df | SS | MS | F | Significance F | |||||||||||||||||||||||
| Regression | 2.0 | 165194.52132082055 | 82597.26066041028 | 29.424083790189602 | 3.014966842563039E-6 | ||||||||||||||||||||||
| Residual | 17.0 | 47721.22867917943 | 2807.131098775261 | ||||||||||||||||||||||||
| Total | 19.0 | 212915.75 | |||||||||||||||||||||||||
| Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | Lower 95.0% | Upper 95.0% | ||||||||||||||||||||
| Intercept | 490.2859264274035 | 44.40984373520935 | 11.040028182731282 | 3.5634214322584356E-9 | 396.5893463057155 | 583.9825065490916 | 396.5893463057155 | 583.9825065490916 | |||||||||||||||||||
| X Variable 1 | -5.149883965250408 | 0.7018867096508137 | -7.3372011386459475 | 1.160619161592546E-6 | -6.630735479145865 | -3.6690324513549504 | -6.630735479145865 | -3.6690324513549504 | |||||||||||||||||||
| X Variable 2 | -14.718148491352501 | 4.933918374976396 | -2.983054718942916 | 0.008350870308799675 | -25.127806338635747 | -4.308490644069256 | -25.127806338635747 | -4.308490644069256 | |||||||||||||||||||
| RESIDUAL OUTPUT | |||||||||||||||||||||||||||
| Observation | Predicted Y | Residuals | Standard Residuals | ||||||||||||||||||||||||
| 1.0 | 265.88554216958175 | -15.885542169581754 | -0.31697355726816207 | ||||||||||||||||||||||||
| 2.0 | 282.0666974697317 | 77.93330253026829 | 1.555048979063293 | ||||||||||||||||||||||||
| 3.0 | 201.86306423892137 | -36.86306423892137 | -0.7355503815280433 | ||||||||||||||||||||||||
| 4.0 | 92.98399756426407 | -49.98399756426407 | -0.9973600740405245 | ||||||||||||||||||||||||
| 5.0 | 81.95272622936452 | 10.047273770635485 | 0.2004791573323606 | ||||||||||||||||||||||||
| 6.0 | 262.1986650131288 | -62.19866501312879 | -1.2410865109970173 | ||||||||||||||||||||||||
| 7.0 | 350.47819582678443 | 4.521804173215571 | 0.09022621568426435 | ||||||||||||||||||||||||
| 8.0 | 307.0552537571256 | -17.055253757125627 | -0.34031349989797866 | ||||||||||||||||||||||||
| 9.0 | 249.67502673497245 | -19.675026734972448 | -0.3925873695058535 | ||||||||||||||||||||||||
| 10.0 | 177.6060113559261 | -57.606011355926114 | -1.1494465939275393 | ||||||||||||||||||||||||
| 11.0 | 35.57441040765153 | 37.42558959234847 | 0.7467747804453648 | ||||||||||||||||||||||||
| 12.0 | 169.50075363862143 | 35.49924636137857 | 0.708337322036852 | ||||||||||||||||||||||||
| 13.0 | 313.6975046656329 | 86.30249533436711 | 1.7220444008285014 | ||||||||||||||||||||||||
| 14.0 | 230.56785781722763 | 89.43214218277237 | 1.7844920833779616 | ||||||||||||||||||||||||
| 15.0 | 63.54770058155907 | 8.45229941844093 | 0.16865369687469584 | ||||||||||||||||||||||||
| 16.0 | 313.6975046656329 | -41.69750466563289 | -0.8320148120836489 | ||||||||||||||||||||||||
| 17.0 | 88.5656170034124 | 5.434382996587601 | 0.10843543717912267 | ||||||||||||||||||||||||
| 18.0 | 166.54537988656722 | 23.45462011343278 | 0.46800381707865324 | ||||||||||||||||||||||||
| 19.0 | 218.77572294347004 | 16.224277056529957 | 0.3237325335083559 | ||||||||||||||||||||||||
| 20.0 | 232.76236803042383 | -93.76236803042383 | -1.8708956241606534 | ||||||||||||||||||||||||
| (a) | Develop scatterplots between January heating costs and each explanatory variable. Fully evaluate. | ||||||||||||||||||||||||||
| (b) | Fully evaluate and compare the estimated linear regressions presented above utilizing the diagnostic regression statistics | ||||||||||||||||||||||||||
| and statistical tests (α=.05 level) discussed in class. | |||||||||||||||||||||||||||
| (c) | Which of the estimated regressions (if any) would you utilize to forecast January heating costs? Briefly justify your answer. | ||||||||||||||||||||||||||
| (d) | Based on your decision related to the "Best" regression equation in part c, generate a forecast. Values of the explanatory variables | ||||||||||||||||||||||||||
| available for possible use in your forecast are provided below. | |||||||||||||||||||||||||||
| Mean January Outside Temperature (X1) | 67.0 | ||||||||||||||||||||||||||
| Age of Furnace (X2) | 11.0 | ||||||||||||||||||||||||||
| YOU NEED LOTS OF DETAIL AND ANALYSIS TO SCORE WELL ON THIS QUESTION | |||||||||||||||||||||||||||
| SEE MY ANSWERS TO EXAM ONE FOR THE LEVEL OF DETAIL RELATED TO REGRSSION EQUATION EVALUATION | |||||||||||||||||||||||||||
| You need to email me back your answers (Excel files, PDF, Word files) in Canvas that clearly present your detailed answers. | |||||||||||||||||||||||||||
| Since this is a take home exam, I expect a lot of detail in the answers and will set a high bar for grading (Higher Than Exam One) | |||||||||||||||||||||||||||
| Due Date: Friday May 11, 2018 at 11:55 p.m. Test answers submitted late will receive a grade of zero. | |||||||||||||||||||||||||||
| There are six questions located in the four workbooks. | |||||||||||||||||||||||||||
| Questions 2 & 3 are to be done by hand (except scatterplots). Show all work. | |||||||||||||||||||||||||||
| Make good use of the Lecture Notes, textbook, and answers to the Problem Sets & Exam One. | |||||||||||||||||||||||||||
| HAVE FUN WITH THIS EXAM |
Temperature vs. Heating Costs
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Temperature
Heating Costs
Age of Furnace vs. Heating Costs
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Age of furnace
Heating Costs
2
R