Statistics Assignment
Assignment 1
1. Below we list several variables. Which of these variables are quantitative and which are qualitative? Explain.
a. The dollar amount on an accounts receivable invoice.
b. The net profit for a company in 2005.
c. The stock exchange on which a company’s stock is traded.
d. The national debt of the United States in 2005.
e. The advertising medium (radio, television, or print) used to promote a product.
2. Classify each of the following qualitative variables as ordinal or nominative. Explain your answers. Qualitative Variables
Categories
Statistics course letter grade
A B C D F
Door choice on Let’s Make A Deal
Door﹟1 Door﹟2
Personal computer ownership
Yes No
Restaurant rating
***** **** *** ** *
Incoming tax filing status
Married filing jointly; Married filing separately;
Single; Head of household; Qualifying widow(er)
3. Explain how to take a systematic sample of 100 companies from the 1,853 companies that are members of an industry trade association.
4. Explain how a stratified random sample is selected.
5. Marketing researchers often use city blocks as clusters in cluster sampling. Using this fact, explain how a market researcher might use multistage cluster sampling to select a sample of consumers from all cities having a population of more than 10,000 in a large state having many such cities.
6. Forbes magazine publishes the Forbes Platinum 400 –a list of the “Best Big Companies in
America” as selected by the magazine’s writers and editors. Table above gives the best companies in the retailing industry as given in this list on the Forbes website on March 16, 2005.
a. Construct a stem-and-leaf display of the profit margin percentages for the best performing retailers as given in Table. Use the whole numbers from 1 to 24 as the stems. Then describe the distribution of profit margins.
b. Construct a stem-and leaf display of the return on capital percentages for the retailers in Table.
Use the whole numbers from 0 to
1. Below we list several variables. Which of these variables are quantitative and which are qualitative? Explain.
a. The dollar amount on an accounts receivable invoice.
b. The net profit for a company in 2005.
c. The stock exchange on which a company’s stock is traded.
d. The national debt of the United States in 2005.
e. The advertising medium (radio, television, or print) used to promote a product.
2. Classify each of the following qualitative variables as ordinal or nominative. Explain your answers. Qualitative Variables
Categories
Statistics course letter grade
A B C D F
Door choice on Let’s Make A Deal
Door﹟1 Door﹟2
Personal computer ownership
Yes No
Restaurant rating
***** **** *** ** *
Incoming tax filing status
Married filing jointly; Married filing separately;
Single; Head of household; Qualifying widow(er)
3. Explain how to take a systematic sample of 100 companies from the 1,853 companies that are members of an industry trade association.
4. Explain how a stratified random sample is selected.
5. Marketing researchers often use city blocks as clusters in cluster sampling. Using this fact, explain how a market researcher might use multistage cluster sampling to select a sample of consumers from all cities having a population of more than 10,000 in a large state having many such cities.
6. Forbes magazine publishes the Forbes Platinum 400 –a list of the “Best Big Companies in
America” as selected by the magazine’s writers and editors. Table above gives the best companies in the retailing industry as given in this list on the Forbes website on March 16, 2005.
a. Construct a stem-and-leaf display of the profit margin percentages for the best performing retailers as given in Table. Use the whole numbers from 1 to 24 as the stems. Then describe the distribution of profit margins.
b. Construct a stem-and leaf display of the return on capital percentages for the retailers in Table.
Use the whole numbers from 0 to