Ch. 1 Defining and Collecting Data (cont) BUS 352 GCU

A study is under way in Yosemite National Forest to determine the adult height of American pine trees. Specifically, the study is attempting to determine what factors aid a tree in reaching heights greater than 60 feet tall. It is estimated that the forest contains 25,000 adult American pines. The study involves collecting heights from 250 randomly selected adult American pine trees and analyzing the results. Identify the sample in the study. a) The 250 randomly selected adult American pine trees. b) The 25,000 adult American pine trees in the forest. c) All the adult American pine trees taller than 60 feet. d) All American pine trees, of any age, in the forest. ANSWER: a

a

A summary measure that is computed to describe a characteristic of an entire population is called a) a parameter. b) an ordered array. c) a statistic. d) a summary table. ANSWER: a

a

Jared was working on a project to look at global warming and accessed an Internet site where he captured average global surface temperatures from 1866. Which of the four methods of data collection was he using? a) Published sources b) Experimentation c) Surveying d) Observation ANSWER: a

a

The chancellor of a major university was concerned about alcohol abuse on her campus and wanted to find out the proportion of students at her university who visited campus bars on the weekend before the final exam week. Her assistant took a random sample of 250 students. The answer on "whether you visited campus bars on the weekend before the final exam week" from students in the sample is an example of __________. a) a categorical variable. b) a discrete variable. c) a continuous variable. d) a table of random numbers. ANSWER: a

a

The classification of student class designation (freshman, sophomore, junior, senior) is an example of a) a categorical variable. b) a discrete variable. c) a continuous variable. d) a table of random numbers. ANSWER: a

a

The classification of student major (accounting, economics, management, marketing, other) is an example of a) a categorical variable. b) a discrete variable. c) a continuous variable. d) a table of random numbers. ANSWER: a

a

The evening host of a dinner dance reached into a bowl, mixed all the tickets around, and selected the ticket to award the grand door prize. What sampling method was used? a) Simple random sample b) Systematic sample c) Stratified sample d) Cluster sample ANSWER: a

a

The manager of the customer service division of a major consumer electronics company is interested in determining whether the customers who have purchased a Blu-ray player made by the company over the past 12 months are satisfied with their products. The population of interest is a) all the customers who have bought a Blu-ray player made by the company over the past 12 months. b) all the customers who have bought a Blu-ray player made by the company and brought itin for repair over the past 12 months. c) all the customers who have used a Blu-ray player over the past 12 months. d) all the customers who have ever bought a Blu-ray player made by the company. ANSWER: a

a

The personnel director at a large company studied the eating habits of the company's employees. The director noted whether employees brought their own lunches to work, ate at the company cafeteria, or went out to lunch. The goal of the study was to improve the food service at the company cafeteria. This type of data collection would best be considered as a) an observational study. b) a designed experiment. c) a random sample. d) a quota sample. ANSWER: a

a

The portion of the universe that has been selected for analysis is called a) a sample. b) a frame. c) a primary data source. d) a secondary data source. ANSWER: a

a

Tim was planning for a meeting with his boss to discuss a raise in his annual salary. In preparation, he wanted to use the Consumer Price Index to determine the percentage increase in his real (inflation-adjusted) salary over the last three years. Which of the 4 methods of data collection was involved when he used the Consumer Price Index? a) Published sources b) Experimentation c) Surveying d) Observation ANSWER: a

a

Which of the following yields a systematic sample? a) All students in a class are divided into groups of 15. One student is randomly chosen from the 1st group, the remaining observations are every 15th student thereafter. b) The best 15 students, according to the opinion of the instructor, in a class are selected. c) All students in a class are grouped according to their gender. A random sample of 8 is selected from the males and a separate random sample of 7 is drawn from the females. d) A random sample of 15 students is selected from a class without replacement. ANSWER: a

a

A company selling apparel online sends out emails every Monday to all its customers who made a purchase. This is an example of a a) systematic sample b) convenience sample c) simple random sample d) stratified sample ANSWER: b

b

A marketing research firm, in conducting a comparative taste test, provided three types of peanut butter to a sample of households randomly selected within the state. Which of the 4 methods of data collection is involved when people are asked to compare the three types of peanut butter? a) Published sources b) Experimentation c) Surveying d) Observation ANSWER: b

b

A population frame for a survey contains a listing of 6,179 names. Using a table of random numbers, which of the following code numbers will appear on your list? a) 06 b) 0694 c) 6946 d) 61790 ANSWER: b

b

A sample of 300 subscribers to a particular magazine is selected from a population frame of 9,000 subscribers. If, upon examining the data, it is determined that no subscriber had been selected in the sample more than once, a) the sample could not have been random. b) the sample may have been selected without replacement or with replacement. c) the sample had to have been selected with replacement. d) the sample had to have been selected without replacement. ANSWER: b

b

A study is under way in Yosemite National Forest to determine the adult height of American pine trees. Specifically, the study is attempting to determine what factors aid a tree in reaching heights greater than 60 feet tall. It is estimated that the forest contains 25,000 adult American pines. The study involves collecting heights from 250 randomly selected adult American pine trees and analyzing the results. Identify the population from which the study was sampled. a) The 250 randomly selected adult American pine trees. b) The 25,000 adult American pine trees in the forest. c) All the adult American pine trees taller than 60 feet. d) All American pine trees, of any age, in the forest. ANSWER: b

b

A telemarketer set the company's computerized dialing system to contact every 25th person listed in the local telephone directory. What sampling method was used? a) Simple random sample b) Systematic sample c) Stratified sample d) Cluster sample ANSWER: b

b

Since a _______ is not a randomly selected probability sample, there is no way to know how well it represents the overall population. a) Simple random sample b) Convenience sample c) Stratified sample d) Cluster sample ANSWER: b

b

The universe or "totality of items or things" under consideration is called a) a sample. b) a population. c) a primary data source. d) a secondary data source. ANSWER: b

b

To gather information on the preferences of instructors at universities on topics for a business statistics textbook that it will publish, a publishing company invited 10 faculty members who have adopted one of the textbooks that it has published. This is an example of a a) systematic sample b) judgment sample c) simple random sample d) stratified sample ANSWER: b

b

To monitor campus security, the campus police office is taking a survey of the number of students in a parking lot each 30 minutes of a 24-hour period with the goal of determining when patrols of the lot would serve the most students. If X is the number of students in the lot each period of time, then X is an example of a) a categorical variable. b) a discrete variable. c) a continuous variable. d) a statistic. ANSWER: b

b

Which of the following can be reduced by proper interviewer training? a) Sampling error b) Measurement error c) Both of the above d) None of the above ANSWER: b

b

Which of the following is most likely a parameter as opposed to a statistic? a) The average score of the first five students completing an assignment. b) The proportion of females registered to vote in a county. c) The average height of people randomly selected from a database. d) The proportion of trucks stopped yesterday that were cited for bad brakes. ANSWER: b

b

Which of the following scenarios will yield a nonprobability sample? a) The subjects of the sample are chosen on the basis of known probability. b) Items or individuals are chosen without regard to their probability of occurrence. c) Every individual or item from the frame has an equal chance of being selected. Selection may be with replacement or without replacement. d) Decide on a sample size, n; divide the frame of N individuals into groups of k individuals where k = N/n; randomly select one individual from the first group; select every kth individual thereafter. ANSWER: b

b

A population frame for a survey contains a listing of 72,345 names. Using a table of random numbers, how many digits will the code numbers for each member of your population contain? a) 3 b) 4 c) 5 d) 6 ANSWER: c

c

A study attempted to estimate the proportion of Florida residents who were willing to spend more tax dollars on protecting the beaches from environmental disasters. Twenty-five hundred Florida residents were surveyed. What type of data collection procedure was most likely used to collect the data for this study? a) A designed experiment b) A published source c) A random sample d) Observational data ANSWER: c

c

A summary measure that is computed to describe a characteristic from only a sample of the population is called a) an ordered array. b) a summary table. c) a statistic. d) a parameter. ANSWER: c

c

Most analysts focus on the cost of tuition as the way to measure the cost of a college education. But incidentals, such as textbook costs, are rarely considered. A researcher at Drummand University wishes to estimate the textbook costs of first-year students at Drummand. To do so, she monitored the textbook cost of 250 first-year students and found that their average textbook cost was $600 per semester. Identify the population of interest to the researcher. a) All Drummand University students. b) All college students. c) All first-year Drummand University students. d) The 250 students that were monitored. ANSWER: c

c

Researchers are concerned that the weight of the average American school child is increasing implying, among other things, that children's clothing should be manufactured and marketed in larger sizes. If X is the weight of school children sampled in a nationwide study, then X is an example of a) a categorical variable. b) a discrete variable. c) a continuous variable. d) a table of random numbers. ANSWER: c

c

Researchers suspect that the average number of units earned per semester by college students is rising. A researcher at Calendula College wishes to estimate the number of units earned by students during the spring semester at Calendula. To do so, he randomly selects 100 student transcripts and records the number of units each student earned in the spring term. He found that the average number of semester units completed was 12.96 units per student. Identify the population of interest to the researcher. a) All Calendula College students. b) All college students. c) All Calendula College students enrolled in the spring. d) All college students enrolled in the spring. ANSWER: c

c

The British Airways Internet site provides a questionnaire instrument that can be answered electronically. Which of the 4 methods of data collection is involved when people complete the questionnaire? a) Published sources b) Experimentation c) Surveying d) Observation ANSWER: c

c

The Dean of Students mailed a survey to a total of 400 students. The sample included 100 students randomly selected from each of the freshman, sophomore, junior, and senior classes on campus last term. What sampling method was used? a) Simple random sample b) Systematic sample c) Stratified sample d) Cluster sample ANSWER: c

c

The chancellor of a major university was concerned about alcohol abuse on her campus and wanted to find out the proportion of students at her university who visited campus bars on the weekend before the final exam week. Her assistant took a random sample of 250 students and computed the portion of students in the sample who visited campus bars on the weekend before the final exam. The portion of all students at her university who visited campus bars on the weekend before the final exam week is an example of a) a categorical variable. b) a discrete variable. c) a parameter. d) a statistic. ANSWER: c

c

The manager of the customer service division of a major consumer electronics company is interested in determining whether the customers who have purchased a Blu-ray player made by the company over the past 12 months are satisfied with their products. Which of the following will be a good frame for drawing a sample? a) Telephone directory. b) Voting registry. c) The list of customers who returned the registration card. d) A list of potential customers purchased from a database marketing company. ANSWER: c

c

To find out the potential impact of a new zoning law on a neighborhood, the legislators conduct a focus group interview by inviting the members of the housing owners association of that neighborhood. This is an example of a a) systematic sample b) simple random sample c) judgment sample d) cluster sample ANSWER: c

c

Which of the following is NOT a reason for selecting a sample? a) A sample is less time consuming than a census. b) A sample is less costly to administer than a census. c) A sample is usually not a good representation of the target population. d) A sample is less cumbersome and more practical to administer. ANSWER: c

c

Which of the following is a continuous quantitative (numerical) variable? a) The color of a student's eyes b) The number of employees of an insurance company c) The amount of milk in a 2-liter carton. d) The number of gallons of milk sold at the local grocery store yesterday ANSWER: c

c

Which of the following sampling methods is a probability sample? a) Convenience sample b) Quota sample c) Stratified sample d) Judgment sample ANSWER: c

c

Which of the following sampling methods will more likely be susceptible to ethical violation when used to form conclusions about the entire population? a) Simple random sample b) Cluster sample c) Judgment sample d) Stratified sample ANSWER: c

c

Which of the following sampling methods will more likely be susceptible to ethical violation? a) Simple random sample b) Cluster sample c) Convenience sample d) Stratified sample ANSWER: c

c

Which of the following yields a simple random sample? a) All students in a class are divided into groups of 15. One student is randomly chosen from the 1st group, the remaining observations are every 15th student thereafter. b) The best 15 students, according to the opinion of the instructor, in a class are selected. c) The names of 50 students in a class are written on 50 different pieces of paper and put in a hat. The first 15 pieces of paper are selected blindly one at a time without replacing them back in the hat after shuffling the papers thoroughly. d) All students in a class are divided into groups according to the rows that they are seated. One of the groups is randomly selected. ANSWER: c

c

Which of the following yields a simple random sample? a) All students in a class are grouped according to their gender. A random sample of 8 is selected from the males and a separate random sample of 7 is drawn from the females. b) The best 15 students, according to the opinion of the instructor, in a class are selected. c) The names of 50 students in a class are written on 50 different pieces of paper and put in a hat. The first 15 pieces of paper are selected blindly one at a time after shuffling the papers thoroughly and each of the selected pieces is placed back into the hat before the next piece is selected. d) All students in a class are divided into groups according to the rows that they are seated. One of the groups is randomly selected. ANSWER: c

c

Which of the following yields a stratified sample? a) All students in a class are divided into groups of 15. One student is randomly chosen from the 1st group, the remaining observations are every 15th student thereafter. b) The best 15 students, according to the opinion of the instructor, in a class are selected. c) All students in a class are grouped according to their gender. A random sample of 8 is selected from the males and a separate random sample of 7 is drawn from the females. d) The first 15 students in a class are selected without replacement. ANSWER: c

c

A statistics student found a reference in the campus library that contained the median family incomes for all 50 states. She would report her data as being collected using a) a designed experiment. b) observational data. c) a random sample. d) a published source. ANSWER: d

d

At US Data Corporation's web site, they advertised that "Because of our commitment to quality and our vast amount of industry knowledge and experience, we have grown to be one of America's leading providers of mailing lists, marketing data, sales leads and research data. We maintain databases of information on consumers and businesses nationwide that set industry standards for mission critical currency, reliability and accuracy." Trying to reach 500 potential donors for their annual phone donation campaign, a local fire department purchased a list of donors from the company. This list is an example of a a) stratified sample b) systematic sample c) judgment sample d) frame ANSWER: d

d

For a population frame containing N = 1,007 individuals, what code number should you assign to the first person on the list in order to use a table of random numbers? a) 0 b) 1 c) 01 d) 0001 ANSWER: d

d

Most analysts focus on the cost of tuition as the way to measure the cost of a college education. But incidentals, such as textbook costs, are rarely considered. A researcher at Drummand University wishes to estimate the textbook costs of first-year students at Drummand. To do so, she monitored the textbook cost of 250 first-year students and found that their average textbook cost was $600 per semester. Identify the sample in the study. a) All Drummand University students. b) All college students. c) All first-year Drummand University students. d) The 250 students that were monitored. ANSWER: d

d

The chancellor of a major university was concerned about alcohol abuse on her campus and wanted to find out the proportion of students at her university who visited campus bars on the weekend before the final exam week. Her assistant took a random sample of 250 students. The portion of students in the sample who visited campus bars on the weekend before the final exam week is an example of __________. a) a summary table. b) a categorical variable. c) a parameter. d) a statistic ANSWER: d

d

To demonstrate a sampling method, the instructor in a class picked the first 5 students sitting in the last row of the class. This is an example of a a) systematic sample b) simple random sample c) stratified sample d) convenience sample ANSWER: d

d

To obtain a sample of 10 books in the store, the manager walked to the first shelf next to the cash register to pick the first 10 books on that shelf. This is an example of a a) systematic sample b) simple random sample c) stratified sample d) convenience sample ANSWER: d

d

Which of the 4 methods of data collection is involved when a person counts the number of cars passing designated locations on the Los Angeles freeway system? a) Published sources b) Experimentation c) Surveying d) Observation ANSWER: d

d

Which of the following is NOT a reason for the need for sampling? a) It is usually too costly to study the whole population. b) It is usually too time consuming to look at the whole population. c) It is sometimes destructive to observe the entire population. d) It is always more informative by investigating a sample than the entire population. ANSWER: d

d

Which of the following is a discrete quantitative (numerical) variable? a) The Dow Jones Industrial average b) The volume of water released from a dam c) The distance you drove yesterday. d) The number of employees of an insurance company ANSWER: d

d

Which of the following is most likely a population as opposed to a sample? a) respondents to a newspaper survey. b) the first 5 students completing an assignment. c) every third person to arrive at the bank. d) registered voters in a county. ANSWER: d

d

Which of the following sampling methods will more likely be susceptible to ethical violation when used to form conclusions about the entire population? a) Simple random sample b) Cluster sample c) Systematic sample d) Convenience sample ANSWER: d

d

Which of the following types of samples can you use if you want to make valid statistical inferences from a sample to a population? a) A judgment sample b) A quota sample c) A convenience sample d) A probability sample ANSWER: d

d

Which of the following yields a cluster sample? a) All students in a class are divided into groups of 15. One student is randomly chosen from the 1st group, the remaining observations are every 15th student thereafter. b) The best 15 students, according to the opinion of the instructor, in a class are selected. c) All students in a class are grouped according to their gender. A random sample of 8 is selected from the males and a separate random sample of 7 is selected from the females. d) All students in a class are divided into groups according to the rows that they are seated. One of the groups is randomly selected. ANSWER: d

d