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HW11
MGMT 650 Summer 2019 Week 11 Homework Answers (Last updated 3/18/2019)
Chi Square
| Saeko has a yarn shop and wants to test her theory on what types of colors she is selling. | ||||||||||
| She believes that Black, White, the Primary Colors, and Tertiary colors sell in equal amounts. | ||||||||||
| Test Saeko's theory using the 5 step hypothesis testing analysis and Chi Square at the .10 level of significance. | ||||||||||
| (optional) | Use the "Pivot Table Data" tab to create a pivot table that shows Saeko the number of yards that were sold in the various yarn types during the busiest weekend of her shop last year. | |||||||||
| The pivot table should contain Color Type, Sum of Yards and Count of Color Type as Column Titles. | ||||||||||
| Color Type | Sum of Yards | Count of Color Type | Here is the pivot table that you should have created. It is optional so that you can practice your pivot table skills. | |||||||
| Black | 19,762.00 | 23 | Color Type | Sum of Yards | Count of Color Type | |||||
| Blue | 8,127.00 | 20 | Black | 19,762.00 | 23 | |||||
| Brown | 8,027.00 | 13 | Blue | 8,127.00 | 20 | |||||
| Green | 6,533.00 | 12 | Brown | 8,027.00 | 13 | |||||
| Purple | 7,243.00 | 12 | Green | 6,533.00 | 12 | |||||
| Red | 5,194.00 | 10 | Purple | 7,243.00 | 12 | |||||
| White | 17,649.00 | 26 | Red | 5,194.00 | 10 | |||||
| Yellow | 7,229.00 | 14 | White | 17,649.00 | 26 | |||||
| Grand Total | 79,764.00 | 130 | Yellow | 7,229.00 | 14 | |||||
| Grand Total | 79,764.00 | 130 | ||||||||
| 1) | Using the pivot table that you just created, fill in the blanks in the following table: | |||||||||
| Primary Colors consists of the sum of Blue, Red, and Yellow yarn sold | ||||||||||
| Tertiary Colors consists of the sum of Brown, Green, and Purple Colors Sold. | ||||||||||
| The Total in this chart must equal the Grand Total, Cell D16 in the above table. | ||||||||||
| Color Type | Sum of Yards | |||||||||
| Black | 19762 | |||||||||
| White | 17649 | |||||||||
| Primary Colors | 20550 | |||||||||
| Tertiary Colors | 21803 | |||||||||
| Total | 79764 | |||||||||
| This table represents the observed data in the Chi Square analysis. | Color Type | Sum of Yards | Count of Color Type | |||||||
| Black | 19,762.00 | 23 | ||||||||
| Subtract the Expected values from the observed values | Blue | 8,127.00 | 20 | |||||||
| Color Type | Sum of Yards | expected value | 9970.5 | Brown | 8,027.00 | 13 | ||||
| Black | 9,791.50 | Green | 6,533.00 | 12 | ||||||
| White | 7,678.50 | Purple | 7,243.00 | 12 | ||||||
| Primary Colors | 10,579.50 | Red | 5,194.00 | 10 | ||||||
| Tertiary Colors | 11,832.50 | White | 17,649.00 | 26 | ||||||
| Total | 39,882.00 | Yellow | 7,229.00 | 14 | ||||||
| Grand Total | 79,764.00 | 130 | ||||||||
| Square the values just found | ||||||||||
| Color Type | Sum of Yards | |||||||||
| Black | ||||||||||
| White | ||||||||||
| Primary Colors | ||||||||||
| Tertiary Colors | ||||||||||
| Divide each square by the expected value and add together | ||||||||||
| Color Type | Sum of Yards | |||||||||
| Black | ||||||||||
| White | ||||||||||
| Primary Colors | ||||||||||
| Tertiary Colors | ||||||||||
| Total | ||||||||||
| This total is your Chi Square test statistic | ||||||||||
| 2) | Use the 5 step hypothesis testing procedure to determine if Saeko's hypothesis that the colors sell in equal amounts is true. | |||||||||
| What is the null hypothesis? | ||||||||||
| What is the alternative hypothesis? | ||||||||||
| What is the level of significance? | ||||||||||
| What is the Chi Square test statistic? | - 0 | |||||||||
| 3) | What is the Chi Square critical Value? | Use =CHISQ.INV() | ||||||||
| 4) | What is your answer to Saeko? | |||||||||
Pivot Table Data
| Customer | Color Name | Color Type | Yards | Meters |
| 1 | Coriander | White | 1,067.00 | 975.66 |
| 2 | Black | Black | 917.00 | 838.50 |
| 3 | Daffodil | Yellow | 762.00 | 696.77 |
| 4 | Black | Black | 735.00 | 672.08 |
| 5 | Opal | Blue | 551.00 | 503.83 |
| 6 | Toffee | Brown | 709.00 | 648.31 |
| 7 | Ruby | Red | 792.00 | 724.20 |
| 8 | Ash | Blue | 830.00 | 758.95 |
| 9 | Black | Black | 670.00 | 612.65 |
| 10 | Ash | Blue | 292.00 | 267.00 |
| 11 | Black | Black | 744.00 | 680.31 |
| 12 | Whirlpool | Blue | 943.00 | 862.28 |
| 13 | Verde | Green | 947.00 | 865.94 |
| 14 | Regal | Purple | 945.00 | 864.11 |
| 15 | Lynx | Brown | 774.00 | 707.75 |
| 16 | Yellow Rose | Yellow | 801.00 | 732.43 |
| 17 | Chocolate | Brown | 750.00 | 685.80 |
| 18 | Mist | White | 629.00 | 575.16 |
| 19 | Whirlpool | Blue | 113.00 | 103.33 |
| 20 | Alfalfa | Green | 344.00 | 314.55 |
| 21 | Ruby | Red | 162.00 | 148.13 |
| 22 | Verde | Green | 964.00 | 881.48 |
| 23 | Sky | White | 517.00 | 472.74 |
| 24 | Black | Black | 1,223.00 | 1,118.31 |
| 25 | Whirlpool | Blue | 200.00 | 182.88 |
| 26 | Black | Black | 879.00 | 803.76 |
| 27 | Mist | White | 999.00 | 913.49 |
| 28 | Alfalfa | Green | 598.00 | 546.81 |
| 29 | Jade | Green | 662.00 | 605.33 |
| 30 | Yellow Rose | Yellow | 368.00 | 336.50 |
| 31 | Cream | White | 529.00 | 483.72 |
| 32 | Black | Black | 1,100.00 | 1,005.84 |
| 33 | Ruby | Red | 870.00 | 795.53 |
| 34 | Mist | White | 342.00 | 312.72 |
| 35 | Yellow Rose | Yellow | 747.00 | 683.06 |
| 36 | Black | Black | 1,160.00 | 1,060.70 |
| 37 | Sky | White | 628.00 | 574.24 |
| 38 | Periwinkle | Purple | 185.00 | 169.16 |
| 39 | Coriander | White | 978.00 | 894.28 |
| 40 | Black | Black | 607.00 | 555.04 |
| 41 | Yellow Rose | Yellow | 387.00 | 353.87 |
| 42 | Black | Black | 255.00 | 233.17 |
| 43 | Periwinkle | Purple | 742.00 | 678.48 |
| 44 | Black | Black | 414.00 | 378.56 |
| 45 | Blush | Red | 345.00 | 315.47 |
| 46 | Black | Black | 892.00 | 815.64 |
| 47 | Mist | White | 727.00 | 664.77 |
| 48 | Coriander | White | 584.00 | 534.01 |
| 49 | Cream | White | 321.00 | 293.52 |
| 50 | Verde | Green | 478.00 | 437.08 |
| 51 | Black | Black | 931.00 | 851.31 |
| 52 | Daffodil | Yellow | 539.00 | 492.86 |
| 53 | Chocolate | Brown | 767.00 | 701.34 |
| 54 | Daffodil | Yellow | 369.00 | 337.41 |
| 55 | Regal | Purple | 378.00 | 345.64 |
| 56 | Daffodil | Yellow | 376.00 | 343.81 |
| 57 | Coriander | White | 957.00 | 875.08 |
| 58 | Black | Black | 929.00 | 849.48 |
| 59 | Black | Black | 959.00 | 876.91 |
| 60 | Lynx | Brown | 994.00 | 908.91 |
| 61 | Periwinkle | Purple | 714.00 | 652.88 |
| 62 | Daffodil | Yellow | 912.00 | 833.93 |
| 63 | Coriander | White | 776.00 | 709.57 |
| 64 | Verde | Green | 895.00 | 818.39 |
| 65 | Lynx | Brown | 706.00 | 645.57 |
| 66 | Alfalfa | Green | 105.00 | 96.01 |
| 67 | Cream | White | 165.00 | 150.88 |
| 68 | Daffodil | Yellow | 505.00 | 461.77 |
| 69 | Periwinkle | Purple | 661.00 | 604.42 |
| 70 | Cream | White | 226.00 | 206.65 |
| 71 | Black | Black | 472.00 | 431.60 |
| 72 | Opal | Blue | 184.00 | 168.25 |
| 73 | Cream | White | 191.00 | 174.65 |
| 74 | Cream | White | 238.00 | 217.63 |
| 75 | Coriander | White | 894.00 | 817.47 |
| 76 | Mist | White | 488.00 | 446.23 |
| 77 | Verde | Green | 400.00 | 365.76 |
| 78 | Black | Black | 1,618.00 | 1,479.50 |
| 79 | Blush | Red | 374.00 | 341.99 |
| 80 | Opal | Blue | 359.00 | 328.27 |
| 81 | Daffodil | Yellow | 553.00 | 505.66 |
| 82 | Mist | White | 439.00 | 401.42 |
| 83 | Alfalfa | Green | 448.00 | 409.65 |
| 84 | Jade | Green | 290.00 | 265.18 |
| 85 | Ruby | Red | 907.00 | 829.36 |
| 86 | Verde | Green | 402.00 | 367.59 |
| 87 | Cream | White | 123.00 | 112.47 |
| 88 | Black | Black | 981.00 | 897.03 |
| 89 | Chocolate | Brown | 247.00 | 225.86 |
| 90 | Regal | Purple | 805.00 | 736.09 |
| 91 | Sky | White | 358.00 | 327.36 |
| 92 | Regal | Purple | 461.00 | 421.54 |
| 93 | Yellow Rose | Yellow | 540.00 | 493.78 |
| 94 | Lynx | Brown | 964.00 | 881.48 |
| 95 | Regal | Purple | 317.00 | 289.86 |
| 96 | Ash | Blue | 190.00 | 173.74 |
| 97 | Periwinkle | Purple | 423.00 | 386.79 |
| 98 | Black | Black | 1,761.00 | 1,610.26 |
| 99 | Black | Black | 912.00 | 833.93 |
| 100 | Blush | Red | 258.00 | 235.92 |
| 101 | Regal | Purple | 968.00 | 885.14 |
| 102 | Sapphire | Blue | 517.00 | 472.74 |
| 103 | Whirlpool | Blue | 362.00 | 331.01 |
| 104 | Yellow Rose | Yellow | 125.00 | 114.30 |
| 105 | Whirlpool | Blue | 504.00 | 460.86 |
| 106 | Sapphire | Blue | 427.00 | 390.45 |
| 107 | Chocolate | Brown | 557.00 | 509.32 |
| 108 | Toffee | Brown | 498.00 | 455.37 |
| 109 | Sapphire | Blue | 216.00 | 197.51 |
| 110 | Whirlpool | Blue | 174.00 | 159.11 |
| 111 | Black | Black | 470.00 | 429.77 |
| 112 | Regal | Purple | 644.00 | 588.87 |
| 113 | Opal | Blue | 436.00 | 398.68 |
| 114 | Blush | Red | 768.00 | 702.26 |
| 115 | Coriander | White | 1,456.00 | 1,331.37 |
| 116 | Whirlpool | Blue | 385.00 | 352.04 |
| 117 | Ash | Blue | 869.00 | 794.61 |
| 118 | Blush | Red | 416.00 | 380.39 |
| 119 | Black | Black | 634.00 | 579.73 |
| 120 | Ruby | Red | 302.00 | 276.15 |
| 121 | Mist | White | 892.00 | 815.64 |
| 122 | Chocolate | Brown | 240.00 | 219.46 |
| 123 | Opal | Blue | 523.00 | 478.23 |
| 124 | Toffee | Brown | 710.00 | 649.22 |
| 125 | Yellow Rose | Yellow | 245.00 | 224.03 |
| 126 | Sky | White | 736.00 | 673.00 |
| 127 | White | White | 2,389.00 | 2,184.50 |
| 128 | Black | Black | 499.00 | 456.29 |
| 129 | Chocolate | Brown | 111.00 | 101.50 |
| 130 | Ash | Blue | 52.00 | 47.55 |
ANOVA
| Saeko owns a yarn shop and want to expands her color selection. | ||||
| Before she expands her colors, she wants to find out if her customers prefer one brand | ||||
| over another brand. Specifically, she is interested in three different types of bison yarn. | ||||
| As an experiment, she randomly selected 21 different days and recorded the sales of each brand. | ||||
| At the .01 significance level, can she conclude that there is a difference in preference between the brands? | ||||
| Misa's Bison | Yak-et-ty-Yaks | Buffalo Yarns | ||
| 343 | 365 | 360 | ||
| 308 | 368 | 346 | ||
| 349 | 351 | 381 | ||
| 304 | 339 | 306 | ||
| 348 | 366 | 314 | ||
| 346 | 331 | 307 | ||
| Total | 1,998.00 | 2,120.00 | 2,014.00 | |
| 5) | What is the null hypothesis? | H0:μ1=μ2=μ3 | ||
| What is the alternative hypothesis? | H1:at least one is different | |||
| What is the level of significance? | 0.01 | |||
| 6) | Use Tools - Data Analysis - ANOVA:Single Factor | |||
| to find the F statistic: | ||||
| 7) | From the ANOVA ooutput: What is the F value? | 1.31 | ||
| 8) | What is the F critical value? | |||
| 9) | What is your decision? | do not reject H0 | ||
Regression
| Studies have shown that the frequency with which shoppers browse Internet retailers is related to the frequency with which they actually purchase products and/or services online. The following data show respondents age and answer to the question “How many minutes do you browse online retailers per week?” | ||||||||||
| Age (X) | Time (Y) | |||||||||
| 13 | 5662 | |||||||||
| 19 | 4549 | |||||||||
| 16 | 3772 | |||||||||
| 44 | 1872 | |||||||||
| 32 | 2799 | |||||||||
| 52 | 1355 | |||||||||
| 39 | 1966 | |||||||||
| 15 | 5682 | |||||||||
| 40 | 1602 | |||||||||
| 53 | 1186 | |||||||||
| 48 | 1832 | |||||||||
| 37 | 2253 | |||||||||
| 36 | 2241 | |||||||||
| 42 | 1001 | |||||||||
| 30 | 2474 | |||||||||
| 42 | 1943 | |||||||||
| 28 | 3021 | |||||||||
| 11 | 5682 | |||||||||
| 32 | 2192 | |||||||||
| 39 | 1784 | |||||||||
| 23 | 2707 | |||||||||
| 37 | 1801 | |||||||||
| 17 | 4827 | |||||||||
| 11 | 2693 | |||||||||
| 18 | 4340 | |||||||||
| 50 | 1399 | |||||||||
| 52 | 1593 | |||||||||
| 9 | 9154 | |||||||||
| 41 | 1504 | |||||||||
| 26 | 2627 | |||||||||
| 30 | 2575 | |||||||||
| 32 | 2711 | |||||||||
| 53 | 2368 | |||||||||
| Column 1 | Column 2 | |||||||||
| 10) | Use Data > Data Analysis > Correlation to compute the correlation checking the Labels checkbox. | Column 1 | 1 | |||||||
| Column 2 | -0.811224516 | 1 | ||||||||
| 11) | Use the Excel function =CORREL to compute the correlation. If answers for #1 and 2 do not agree, there is an error. | -0.8112 | ||||||||
| The strength of the correlation motivates further examination. | ||||||||||
| 12) | a) Insert Scatter (X, Y) plot linked to the data on this sheet with Age on the horizontal (X) axis. | |||||||||
| b) Add to your chart: the chart name, vertical axis label, and horizontal axis label. | ||||||||||
| c) Complete the chart by adding Trendline and checking boxes | ||||||||||
| Read directly from the chart: | ||||||||||
| 13) | a) Intercept = | 6,223 | ||||||||
| b) Slope = | 103.27 | |||||||||
| c) R2 = | 0.6581 | |||||||||
| Perform Data > Data Analysis > Regression. | ||||||||||
| 14) | Highlight the Y-intercept with yellow. Highlight the X variable in blue. Highlight the total standard error in orange | |||||||||
| SUMMARY OUTPUT | ||||||||||
| Regression Statistics | ||||||||||
| Multiple R | 0.811224516 | |||||||||
| R Square | 0.6580852154 | |||||||||
| Adjusted R Square | 0.6470557062 | |||||||||
| Standard Error | 1032.1123255325 | |||||||||
| Observations | 33 | |||||||||
| ANOVA | ||||||||||
| df | SS | MS | F | Significance F | ||||||
| Regression | 1 | 63559412.8144274 | 63559412.8144274 | 59.6658658709 | 0.0000000103 | |||||
| Residual | 31 | 33022931.4279968 | 1065255.85251603 | |||||||
| Total | 32 | 96582344.2424242 | ||||||||
| Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | Lower 95.0% | Upper 95.0% | |||
| Intercept | 6223.0419255764 | 468.1432087866 | 13.2930304419 | 0 | 5268.2575564169 | 7177.8262947359 | 5268.2575564169 | 7177.8262947359 | ||
| Age (X) | -103.27402394 | 13.3698989644 | -7.7243683153 | 0.0000000103 | -130.542112655 | -76.0059352251 | -130.542112655 | -76.0059352251 | ||
| Use Excel to predict the number of minutes spent by a 37-year old shopper. Enter = followed by the regression formula. | ||||||||||
| 15) | Enter the intercept and slope into the formula by clicking on the cells in the regression output with the results. | |||||||||
| 16) | Is it appropriate to use this data to predict the amount of time that a 68-year-old will be on the Internet? | |||||||||
| If yes, what is the amount of time, if no, why? | ||||||||||
Minutes spent online window shopping
Time (Y)
13 19 16 44 32 52 39 15 40 53 48 37 36 42 30 42 28 11 32 39 23 37 17 11 18 50 52 9 41 26 30 32 53 5662 4549 3772 1872 2799 1355 1966 5682 1602 1186 1832 2253 2241 1001 2474 1943 3021 5682 2192 1784 2707 1801 4827 2693 4340 1399 1593 9154 1504 2627 2575 2711 2368
Age (Years)
Time (mins)
Cleaning Data with Outlier
| 17) | On this worksheet, make an XY scatter plot linked to the following data: | |
| X | Y | |
| 92 | 22 | |
| 87 | 23 | |
| 102 | 23 | |
| 80 | 25 | |
| 91 | 27 | |
| 100 | 20 | |
| 95 | 21 | |
| 109 | 19 | |
| 77 | 28 | |
| 100 | 221 | |
| 98 | 25 | |
| 89 | 27 | |
| 97 | 23 | |
| 93 | 22 | |
| 89 | 27 | |
| 91 | 22 | |
| 97 | 21 | |
| 105 | 21 | |
| 88 | 22 | |
| 83 | 24 | |
| 86 | 27 | |
| 89 | 26 | |
| 79 | 30 | |
| 88 | 22 | |
| 94 | 24 | |
| 18) | Add trendline, regression equation and r squared to the plot. | |
| Add this title. ("Scatterplot of X and Y Data") | ||
| 19) | The scatterplot reveals a point outside the point pattern. Copy the data to a new location in the worksheet. You now have 2 sets of data. | |
| Data that are more tha 1.5 IQR below Q1 or more than 1.5 IQR above Q3 are considered outliers and must be investigated. | ||
| It was determined that the outlying point resulted from data entry error. Remove the outlier in the copy of the data. | ||
| Make a new scatterplot linked to the cleaned data without the outlier, and add title ("Scatterplot without Outlier,") trendline, and regression equation label. | ||
| Compare the regression equations of the two plots. How did removal of the outlier affect the slope and R2? | ||
| 20) | ||
Scatterplot of X and Y Data
Y
92 87 102 80 91 100 95 109 77 100 98 89 97 93 89 91 97 105 88 83 86 89 79 88 94 22 23 23 25 27 20 21 19 28 221 25 27 23 22 27 22 21 21 22 24 27 26 30 22 24