Concept explainers
Jack Lawler, a financial analyst, wants to prepare an article on the Shadow Stock portfolio developed by the American Association of Individual Investors (AAII). A list of the 30 companies in the Shadow Stock portfolio as of March 2014 is contained in the DATAfile named ShadowStocks (AAII website March 27, 2014). Jack would like to select a simple random sample of 5 of these companies for an interview concerning management practices.
- a. In the DATAfile the Shadow Stock companies are listed in column A of an Excel worksheet. In column B we have generated a random number for each of the companies. Use these random numbers to select a simple random sample of 5 of these companies for Jack.
- b. Generate a new set of random numbers and use them to select a new simple random sample. Did you select the same companies?
a.
Draw a random sample of 5 of the companies of Jack.
Answer to Problem 42SE
The random sample of 5 of these companies are tabulated below,
Company |
Random Number |
Hardinge Inc. (HDNG) | 0.4298384 |
Medical Action Industries (MDCI) | 0.3792011 |
Mitcham Industries, Inc. (MIND) | 0.4257654 |
Rocky Brands Inc (RCKY) | 0.7556817 |
Willis Lease Finance Corporati (WLFC) | 0.9063183 |
Explanation of Solution
Calculation:
Answers may vary. One of the possible answers is given:
The given data represents the Shadow Stock of 30 companies.
Software procedure:
Step-by-step software procedure to obtain a random samples using MINITAB software:
- Click on Calc > Random Data > Sample from columns.
- In Number of rows to sample, enter 5.
- In the Store in column, enter column C2.
- Click OK.
- Click on Data > Display Data
- Select C2.
- Click Ok.
Output using MINITAB software is as follows:
Therefore, the random sample of 5 of these companies is,
Company |
Random Number |
Hardinge Inc. (HDNG) | 0.4298384 |
Medical Action Industries (MDCI) | 0.3792011 |
Mitcham Industries, Inc. (MIND) | 0.4257654 |
Rocky Brands Inc (RCKY) | 0.7556817 |
Willis Lease Finance Corporati (WLFC) | 0.9063183 |
b.
Generate a new simple random sample and compare it with the sample in part (a).
Answer to Problem 42SE
The random sample of 5 of these companies is,
Company |
Random Number |
Marlin Business Services Corp. (MRLN) | 0.6827254 |
International Shipholding Corp (ISH) | 0.227759457 |
VOXX International Corp (VOXX) | 0.629674789 |
Hardinge Inc. (HDNG) | 0.429838402 |
Rocky Brands Inc (RCKY) | 0.755681737 |
The random samples in these data set does not match with the random samples of part (a).
Explanation of Solution
Calculation:
Software procedure:
Step-by-step software procedure to obtain a random sample using MINITAB software is as follows,
- Click on Calc > Random Data > Sample from columns.
- In Number of rows to sample, enter 5.
- In the Store in column, enter column C2.
- Click OK
- Click on Data > Display Data
- Select C2.
- Click Ok.
Output using MINITAB software is as follows,
Therefore the random sample of 5 of these companies is,
Company |
Random Number |
Marlin Business Services Corp. (MRLN) | 0.6827254 |
International Shipholding Corp (ISH) | 0.227759457 |
VOXX International Corp (VOXX) | 0.629674789 |
Hardinge Inc. (HDNG) | 0.429838402 |
Rocky Brands Inc (RCKY) | 0.755681737 |
Here, it is observed that the drawn sample is not same as the sample drawn in part (a).
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Chapter 7 Solutions
CENGAGENOW FOR ANDERSON/SWEENEY/WILLIAM
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