ECON15A
Pollsters regularly conduct opinion polls to determine the popularity rating of the current president. Suppose a poll is to be conducted tomorrow in which 6,000 individuals will be asked whether the president is doing a good or bad job. The 6,000 individuals will be selected by random-digit telephone dialing and asked the question over the phone. What is the inference of interest to the pollster? A. Estimate the proportion of all citizens who believe the president is doing a good job B. Estimate the number of people in the country C. Estimate the number of people surveyed D. Estimate the number of people who will respond to the survey
A
Pollsters regularly conduct opinion polls to determine the popularity rating of the current president. Suppose a poll is to be conducted tomorrow in which 6,000 individuals will be asked whether the president is doing a good or bad job. The 6,000 individuals will be selected by random-digit telephone dialing and asked the question over the phone. What is the relevant population? A. All people in the country B. The 6,000 individuals surveyed C. All people who respond that the president is doing a good job D. All people who do not respond to the survey
A
Pollsters regularly conduct opinion polls to determine the popularity rating of the current president. Suppose a poll is to be conducted tomorrow in which 6,000 individuals will be asked whether the president is doing a good or bad job. The 6,000 individuals will be selected by random-digit telephone dialing and asked the question over the phone. What is the variable of interest? A. The president's job performance B. If the question was answered C. The number of people surveyed D. The number of people in the country
A
Pollsters regularly conduct opinion polls to determine the popularity rating of the current president. Suppose a poll is to be conducted tomorrow in which 6,000 individuals will be asked whether the president is doing a good or bad job. The 6,000 individuals will be selected by random-digit telephone dialing and asked the question over the phone. What is the sample? A. The 6,000 individuals surveyed B. All people in the country C. All people who respond that the president is doing a good job D. All people who do not respond to the survey
A
Suppose you're given a data set that classifies each sample unit into one of four categories: A, B, C, or D. You plan to create a computer database consisting of these data, and you decide to code the data as A=1, B=2, C=3, and D=4. Are the data consisting of the classifications A, B, C, and D qualitative or quantitative? A. Quantitative, because they can only be classified into categories. B. Qualitative, because they can only be classified into categories. C. Qualitative, because they are measured on a naturally occurring numerical scale. D. Quantitative, because they are measured on a naturally occurring numerical scale.
B
Suppose you're given a data set that classifies each sample unit into one of four categories: A, B, C, or D. You plan to create a computer database consisting of these data, and you decide to code the data as A=1, B=2, C=3, and D=4. After the data are input as 1, 2, 3, or 4, are they qualitative or quantitative? A. Qualitative, because they are measured on a naturally occurring numerical scale. B. Qualitative, because they cannot be meaningfully added, subtracted, multiplied, or divided. C. Quantitative, because they cannot be meaningfully added, subtracted, multiplied, or divided. D. Quantitative, because they are measured on a naturally occurring numerical scale.
B
What is a representative sample? What is its value? A. A representative sample is a sample that is selected at random from the population of interest. It is valuable because its unbiased nature allows descriptive statistics to be applied. B. A representative sample is a sample that exhibits characteristics typical of those possessed by the population of interest. It is valuable because these characteristics allow inferential statistics to be applied. C. A representative sample is a sample that exhibits characteristics typical of those possessed by the population of interest. It is valuable because these characteristics allow descriptive statistics to be applied. D. A representative sample is a sample that is selected at random from the population of interest. It is valuable because its unbiased nature allows inferential statistics to be applied.
B
Explain the difference between descriptive and inferential statistics. Choose the correct answer below. A. Descriptive statistics are measurements that are recorded on a naturally occurring numerical scale. Inferential statistics are measurements that cannot be measured on a natural number scale; they can only be classified into one of a group of categories. B. Descriptive statistics is a characteristic or property of an individual experimental unit. Inferential statistics is the process used to assign numbers to variables of individual population units. C. Descriptive statistics describes sets of data. Inferential statistics draws conclusions about the sets of data based on sampling. D. Descriptive statistics draws conclusions about the sets of data based on sampling. Inferential statistics summarizes the information revealed in data sets.
C
Pollsters regularly conduct opinion polls to determine the popularity rating of the current president. Suppose a poll is to be conducted tomorrow in which 6,000 individuals will be asked whether the president is doing a good or bad job. The 6,000 individuals will be selected by random-digit telephone dialing and asked the question over the phone. How likely is the sample to be representative? A. Very likely, because the sample contains people who have telephones and the sample size is large. B. Very likely, because the sample is a simple random sample and the sample size is large. C. Not very likely, because only people with telephones that are willing to answer a survey will be counted in the results. D. Not very likely, because the sample is a simple random sample and the sample size is large.
C
Pollsters regularly conduct opinion polls to determine the popularity rating of the current president. Suppose a poll is to be conducted tomorrow in which 6,000 individuals will be asked whether the president is doing a good or bad job. The 6,000 individuals will be selected by random-digit telephone dialing and asked the question over the phone. Is the variable quantitative or qualitative? A. The variable is a quantitative variable. Its values can be expressed on a naturally occurring numerical scale. B. The variable is a quantitative variable. Its values cannot be expressed on a naturally occurring numerical scale. C. The variable is a qualitative variable. Its values cannot be expressed on a naturally occurring numerical scale. D. The variable is a qualitative variable. Its values can be expressed on a naturally occurring numerical scale.
C