stat analysis homework and excel lab
Question 1 Prob 10-22
| Tutorial | EXCEL INSTRUCTIONS: | JMP INSTRUCTIONS: | |||||||||||||||
| DS 123 Lab #4 | 1. Under File, select Page Setup. Select the top tab: Sheet. | To add the JMP output for Problem 10.22: | |||||||||||||||
| In the Print window, select Gridlines and Row and Column Headers. | a. Open JMP. | ||||||||||||||||
| 2. Set column A to width 10 and column C to 16. | b. File – New – Data Table. | ||||||||||||||||
| 3. Insert a page break above row 46. | c. Column 1 enter Miller's in cells 1 – 10, Albert's in cells 11 - 20. | ||||||||||||||||
| d. Rename column 1 Markets. | |||||||||||||||||
| Question 1. | Problem 10.10, pp. 389 - 390 | e. Go back to this Excel spreadsheet. Copy Miller's values from Excel. On JMP table, double click on column 2 cell 1, Control-V to paste the ten values. | |||||||||||||||
| Miller's | t-Test: Two-Sample Assuming Equal Variances | f. Go back to this Excel spreadsheet. Copy Albert's values from Excel. On JMP table, paste the values in column 2 cells 11-20. | |||||||||||||||
| $119.25 | Go to the Data ribbon and select Data Analysis. | g. Rename column Grocery Expenses. | |||||||||||||||
| $121.32 | Miller's | Albert's | Select t-Test: Two-Sample Assuming Equal Variances | h. Highlight Grocery Expenses title, select Col-Column info. In the window, format – Dec should show 2, not 0. Click OK. | |||||||||||||
| $122.34 | Mean | 121.916 | 114.807 | Select the data streams for each variable, including their labels. | i. Analyze-Fit Y by X. | ||||||||||||
| $120.14 | Variance | 1.9550044444 | 3.3867122222 | Change the alpha level to .01 | j. Move Grocery Expenses to Y, Response. Move Markets to X, Factor. Click OK. | ||||||||||||
| $122.19 | Observations | 10 | 10 | Mark that labels were included. | k. Click the red diamond next to Oneway Analysis. | ||||||||||||
| $123.71 | Pooled Variance | 2.6708583333 | Place the output in cell C8. | Select Means/Anova/Pooled t. | |||||||||||||
| $121.72 | Hypothesized Mean Difference | 0 | It will prompt you that you are overwriting | l. ALT-Edit-Copy. | |||||||||||||
| $122.42 | df | 18 | material. Click 'Ok'. | m. Go back to this Excel spreadsheet. In cell M23, paste the JMP report. | |||||||||||||
| $123.63 | t Stat | 9.7267575315 | n. From the JMP report, right click on the Oneway Analysis graphic. Edit-Copy graph. | ||||||||||||||
| $122.44 | P(T<=t) one-tail | 0.0000000068 | o. On this Excel spreadsheet, paste the graph with the upper left corner located on P27. | ||||||||||||||
| t Critical one-tail | 2.5523786462 | p. From the JMP report, right click on the t-Test assuming equal variances graphic. Edit – Copy graph. | |||||||||||||||
| Albert's | P(T<=t) two-tail | 0.0000000137 | q. On this Excel spreadsheet, paste the graph with the upper left corner located on cell R48. | ||||||||||||||
| $111.99 | t Critical two-tail | 2.8784415917 | |||||||||||||||
| $114.88 | JMP OUTPUT | ||||||||||||||||
| $115.11 | t-Statistic | p-value | |||||||||||||||
| $117.02 | |||||||||||||||||
| $116.89 | Hypotheses: | Oneway Analysis of Grocery Expenses By Markets | |||||||||||||||
| $116.62 | |||||||||||||||||
| $115.38 | |||||||||||||||||
| $114.40 | Rejection Region: | a = 0.01 | a = 0.01 | ||||||||||||||
| $113.91 | df = 18 | Rej H0 if p-value < 0.01 | |||||||||||||||
| $111.87 | t-coeff = | 2.8784404727 | Oneway Anova | ||||||||||||||
| Rej H0 if t > 2.878 or | |||||||||||||||||
| t < - 2.878 | |||||||||||||||||
| Test Statistic: | t = | 9.7267575315 | p-value = | 0.0000000137 | Summary of Fit | ||||||||||||
| Conclusion: | |||||||||||||||||
| Since the test statistic of t = 9.727 falls | Since the test statistic of | Rsquare | 0.840156 | ||||||||||||||
| WAY above the upper critical value | p-value = 1.37 x 10^-8 falls below | Adj Rsquare | 0.831276 | ||||||||||||||
| of t = 2.878, we reject H0 | alpha=0.01,we reject | Root Mean Square Error | 1.634276 | ||||||||||||||
| with at least 99% confidence. | H0 with at least 99% confidence. | Mean of Response | 118.3615 | ||||||||||||||
| Implication: | Observations (or Sum Wgts) | 20 | |||||||||||||||
| There is enough evidence to | There is enough evidence to | ||||||||||||||||
| conclude that the mean weekly expenses | conclude that the mean weekly | ||||||||||||||||
| at Miller's and Albert's differ. | expenses at Miller's and Albert's | ||||||||||||||||
| differ. | |||||||||||||||||
| t Test | |||||||||||||||||
| Miller's-Albert's | |||||||||||||||||
| Assuming equal variances | |||||||||||||||||
| Difference | 7.109 | t Ratio | 9.726758 | ||||||||||||||
| Std Err Dif | 0.73087 | DF | 18 | ||||||||||||||
| Upper CL Dif | 8.6445 | Prob > |t| | <.0001 | ||||||||||||||
| Lower CL Dif | 5.5735 | Prob > t | <.0001 | ||||||||||||||
| Confidence | 0.95 | Prob < t | 1 | ||||||||||||||
| Analysis of Variance | |||||||||||||||||
| Source | DF | Sum of Squares | Mean Square | F Ratio | Prob > F | ||||||||||||
| Markets | 1 | 252.6894 | 252.689 | 94.6098 | <.0001 | ||||||||||||
| Error | 18 | 48.07545 | 2.671 | ||||||||||||||
| C. Total | 19 | 300.76485 | |||||||||||||||
| Means for Oneway Anova | |||||||||||||||||
| Level | Number | Mean | Std Error | Lower 95% | Upper 95% | ||||||||||||
| Albert's | 10 | 114.807 | 0.5168 | 113.72 | 115.89 | ||||||||||||
| Miller's | 10 | 121.916 | 0.5168 | 120.83 | 123 | ||||||||||||
| Std Error uses a pooled estimate of error variance |
Question 2
| JMP INSTRUCTIONS | |||||||||||||||||||
| Question 2. | Problem Given on Assignment | To add the JMP output for question 2: | |||||||||||||||||
| Branch A | F-Test Two-Sample for Variances | Go to the Data ribbon and select Data Analysis. | a. Open JMP. | ||||||||||||||||
| $307,000 | Select F-Test Two-Sample for Variances | b. File – New – Data Table. | |||||||||||||||||
| $316,000 | Branch A | Branch B | Select the data streams for each variable, including their labels. | c. Column 1 enter Branch A in cells 1 – 14, Branch B in cells 15 – 30. | |||||||||||||||
| $307,000 | Mean | 301500 | 290312.5 | Mark that labels were included. | d. Rename column 1 Branches | ||||||||||||||
| $305,000 | Variance | 269653846.153846 | 97562500 | Change the alpha level to 0.10 -- so the one-tailed critical bound will be at 0.05. | e. Go back to this Excel spreadsheet. Copy Branch A loan values from Excel. On JMP table, double click on column 2 cell 1, Control-V to paste the fourteenvalues. | ||||||||||||||
| $294,000 | Observations | 14 | 16 | Place the output in cell C47. | f. Go back to this Excel spreadsheet. Copy Branch B loan values from Excel. On JMP table, paste the values in column 2 cells 15 – 30. | ||||||||||||||
| $303,000 | df | 13 | 15 | It will prompt you that you are overwriting | g. Rename column Loans. | ||||||||||||||
| $297,000 | F | 2.763908737 | material. Click 'Ok'. | h. Analyze-Fit Y by X. | |||||||||||||||
| $286,000 | P(F<=f) one-tail | 0.0314249074 | Notice: you will REJECT H0. There IS enough evidence to say the variances are different! | i. Move Loans to Y, Response. Move Branches to X, Factor. Click OK. | |||||||||||||||
| $265,000 | F Critical one-tail | 2.0001493795 | j. Click the red diamond next to Oneway Analysis. | ||||||||||||||||
| $320,000 | Select t-Test. | ||||||||||||||||||
| $315,000 | t-Test: Two-Sample Assuming Unequal Variances | k. ALT-Edit-Copy. | |||||||||||||||||
| $328,000 | Go to the Data ribbon and select Data Analysis. | l. Go back to this Excel spreadsheet. In cell P20, paste the JMP report. | |||||||||||||||||
| $285,000 | Branch A | Branch B | Since you rejected H0 on the F-test above, you will | m. From the JMP report, right click on the t-Test assuming unequal variances graphic. Edit – Copy graph. | |||||||||||||||
| $293,000 | Mean | 301500 | 290312.5 | select t-Test: Two-Sample Assuming Unequal Variances | n. On this Excel spreadsheet, paste the graph with the upper left corner located on cell U27. | ||||||||||||||
| Variance | 269653846.153846 | 97562500 | Select the data streams for each variable, including their labels. | ||||||||||||||||
| Branch B | Observations | 14 | 16 | Mark that labels were included. | JMP OUTPUT | ||||||||||||||
| $304,000 | Hypothesized Mean Difference | 0 | Place the output in cell C58. | ||||||||||||||||
| $289,000 | df | 21 | It will prompt you that you are overwriting | ||||||||||||||||
| $296,000 | t Stat | 2.2216212668 | material. Click 'Ok'. | Oneway Analysis of Loans By Branches | |||||||||||||||
| $283,000 | P(T<=t) one-tail | 0.0187168709 | Notice: the df is NOT equal to n1 + n2 - 2. | ||||||||||||||||
| $281,000 | t Critical one-tail | 1.7207435121 | |||||||||||||||||
| $301,000 | P(T<=t) two-tail | 0.0374337418 | |||||||||||||||||
| $298,000 | t Critical two-tail | 2.0796142053 | |||||||||||||||||
| $303,000 | t Test | ||||||||||||||||||
| $301,000 | t-Statistic | p-value | Branch B-Branch A | ||||||||||||||||
| $288,000 | |||||||||||||||||||
| $298,000 | Hypotheses: | Assuming unequal variances | |||||||||||||||||
| $286,000 | |||||||||||||||||||
| $284,000 | |||||||||||||||||||
| $283,000 | Rejection Region: | a = 0.05 | a = 0.05 | ||||||||||||||||
| $277,000 | df = 21 | Rej H0 if p-value < 0.05 | Difference | -11188 | t Ratio | -2.22162 | |||||||||||||
| $273,000 | t-coeff = | 2.0796138447 | Std Err Dif | 5036 | DF | 20.73312 | |||||||||||||
| Rej H0 if t < -2.08 or | Upper CL Dif | -707 | Prob > |t| | 0.0376 | |||||||||||||||
| t > 2.08 | Lower CL Dif | -21668 | Prob > t | 0.9812 | |||||||||||||||
| Test Statistic: | t = | 2.2216212668 | p-value = | 0.0374337432 | Confidence | 0.95 | Prob < t | 0.0188 | |||||||||||
| Conclusion: | |||||||||||||||||||
| Since the test statistic of t = 2.222 falls | Since the test statistic of | ||||||||||||||||||
| abovethe upper critical | p-value = .037 falls below | ||||||||||||||||||
| value of t = 2.080, we reject | a = 0.05, we reject | Tests that the Variances are Equal | |||||||||||||||||
| H0 with at least 95% confidence. | H0 with at least 95% confidence. | ||||||||||||||||||
| Implication: | |||||||||||||||||||
| There is enough evidence to | There is enough evidence to | Level | Count | Std Dev | MeanAbsDif to Mean | MeanAbsDif to Median | |||||||||||||
| conclude that the average weekly | to conclude that the average | Branch A | 14 | 16421.14 | 12714.29 | 12500 | |||||||||||||
| expenses differs for the two stores. | weekly expenses differ | Branch B | 16 | 9877.37 | 8601.56 | 8437.5 | |||||||||||||
| for the two stores. | |||||||||||||||||||
| Test | F Ratio | DFNum | DFDen | p-Value | |||||||||||||||
| O'Brien[.5] | 2.7 | 1 | 28 | 0.1115 | |||||||||||||||
| Brown-Forsythe | 1.9358 | 1 | 28 | 0.1751 | |||||||||||||||
| Levene | 2.3234 | 1 | 28 | 0.1387 | |||||||||||||||
| Bartlett | 3.4123 | 1 | . | 0.0647 | |||||||||||||||
| F Test 2-sided | 2.7639 | 13 | 15 | 0.0628 | |||||||||||||||
| Welch's Test | |||||||||||||||||||
| Welch Anova testing Means Equal, allowing Std Devs Not Equal | |||||||||||||||||||
| F Ratio | DFNum | DFDen | Prob > F | ||||||||||||||||
| 4.9356 | 1 | 20.733 | 0.0376 | ||||||||||||||||
| t Test | |||||||||||||||||||
| 2.2216 |
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