Qnt 561 week 1 practice problems

QNT 561 Week 1 Practice Quiz

1. What is statistics?

A. It is the science that deals with collection, classification, analysis, and interpretation of information or data.

B. It is the process used to assign numbers to variables of individual population units.

C. It is an estimate or prediction or some other generalization about a population based on information contained in a sample.

D. It is a characteristic or property of an individual experimental unit.

2. Choose the correct answer below.

A. Descriptive statistics is a characteristic of an individual experimental unit. Inferential statistics is the process used to assign numbers to variable of individual population units.

B. Descriptive statistics describes sets of data. Inferential statistics draws conclusion about the sets of data based on sampling.

C. Descriptive statistics are measurements that are recorded on a naturally occurring numerical scale; they can only be classified into one of a group of categories.

D. Descriptive statistics draws conclusions about the sets of data based on sampling. Inferential statistics summarizes the information revealed in data sets.

3. Choose the correct answer below.

A. Qualitative data are data from a population, while qualitative data are data from a sample.

B. Quantitative data are categorical in nature, while qualitative data are numerical in nature.

C. Quantitative data are collected from an observational study, while qualitative data are from a designed experiment.

D. Quantitative data are numerical in nature, while qualitative data are categorical in nature.

E. Quantitative data are collected from a designed experiment, while qualitative data are from an observational study.

F. Quantitative data are data from a sample, while qualitative data are data from a population.

4. Choose the correct answer below.

A. A population is a set of units of interest to a study. A variable is a subset of the units of a population.

B. A population is a set of units of interest of a study. A variable is an object upon which data is collected.

C. A population is a set of units of interest of a study. A variable is a characteristics or property of the units being studied.

D. A variable is a set of units of interest to study. A population is a characteristic or property of the units being studied.

5. Choose the correct answer below.

A. A sample is a set of measurements that are recorded on a naturally occurring numerical scale. A population is a set of measurements that cannot be measured on a natural numerical scale; they can only be classified into one of a group of categories.

B. A sample is a set of units of interest to a study. A population is a subset of the units of a sample.

C. A population is a set of units of interest of a study. A sample is a subset of the units of a population.

D. A population is an object upon which data is collected. A sample is a characteristics or property of an individual experimental unit.

6. Choose the correct answer below.

A. A representative sample is a subset of the units of a population.

B. A representative sample is a sample that exhibits characteristics typical of those possessed by the population of interest.

C. A representative sample is a set of units of interest of study.

D. A representative sample of n experimental unites is a sample from the population in such a way that every different sample of size n has an equal chance of selection.

7. Choose the correct answer below.

A. A process is categorical in nature. A population is numerical in nature.

B. A process produces or generates output over time. A population is a process whose operations or actions are unknown or unspecified.

C. A population is a set of existing units. A process produces or generates output over time.

D. A population is a set of existing units. A process is a subset of population.

8. Choose the correct answer below.

A. Statistical thinking is a series of actions or operations that transforms inputs or outputs.

B. Statistical thinking is a statement about the degree of uncertainty associated with statistical inference.

C. Statistical thinking utilizes sample data to make estimates, decisions, predictions, or other generalizations about a larger set of data.

D. Statistical thinking involves applying rational thought and the science of statistics to critically assess data and inferences.

9. Suppose you’re given a data set that classifies each sample unit into one of the 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, D qualitative or quantitative? After the data are input as 1, 2, 3, or 4, are they qualitative or quantitative?

Are the data consisting of the classification A, B, C, D qualitative or quantitative?

A. Qualitative, because they are measured on a naturally occurring numerical scale.

B. Quantitative, because they can only be classified into categories.

C. Qualitative, because they can only be classified into categories.

D. Quantitative, because they are measured on a naturally occurring numerical scale.

After the data are input as 1, 2, 3, or 4, are they qualitative or quantitative.

A. Qualitative, because they cannot be meaningfully added, subtracted, multiplied, or divided.

B. Quantitative, because they are measured on a naturally occurring numerical scale.

C. Qualitative, because they are measured on a naturally occurring numerical scale.

D. Quantitative, because they cannot be meaningfully added, subtracted, multiplied, or divided.

10. Identify each of the following variables as qualitative or quantitative.

a. Number of children in family.

b. Native language

c. Number of pets in family

d. Lucky day of the week

A. Is the variable qualitative or quantitative? Why?

A. Number of children in family is a quantitative variable. Its values are numerical.

B. Number of children in family is a qualitative variable. Its values are numerical.

C. Number of children in family is a quantitative variable. Its values are not numerical.

D. Number of children in family is a qualitative variable. Its values are not numerical.

B. Is the variable qualitative or quantitative? Why?

A. Native language is a qualitative variable. Its values are numerical.

B. Native language is a quantitative variable. Its values are numerical.

C. Native language is a qualitative variable. Its values are not numerical.

D. Native language is a quantitative variable. Its values are not numerical.

C. Is the variable qualitative or quantitative? Why?

A. Number of pets in family is a quantitative variable. Its values are numerical.

B. Number of pets in family is a qualitative variable. Its values are numerical.

C. Number of pets in family is a qualitative variable. Its values are not numerical.

D. Number of pets in family is a quantitative variable. Its values are not numerical.

D. Is the variable qualitative or quantitative? Why?

A. Lucky day of the week is a qualitative variable. Its values are not numerical.

B. Lucky day of the week is a quantitative variable. Its values are not numerical.

C. Lucky day of the week is a quantitative variable. Its values are numerical.

D. Lucky day of the week is a qualitative variable. Its values are numerical.

10b. Identify each of the following variables as qualitative or quantitative.

a. Profession

b. Size of home

c. Distance of commute to work

d. Gender

A. Is the variable qualitative or quantitative? Why?

Profession is a qualitative variable. Its values are numerical.

Profession is a quantitative variable. Its values are not numerical.

Profession is a quantitative variable. Its values are numerical.

Profession is a qualitative variable. Its values are not numerical.

B. Is the variable qualitative or quantitative? Why?

Size of home is a quantitative variable. Its values are numerical.

C. Is the variable qualitative or quantitative? Why?

Distance of commute to work is a quantitative variable. Its values are numerical.

D. Is the variable qualitative or quantitative? Why?

Gender is a qualitative variable. Its values are not. Numerical.

11. Each month interviewers visit about 39,000 of the 93 million households in the region and question the occupants over 18 years of age about their marriage status. Their responses enable the interviewers to estimate the percentage of people in the labor force who are married. Complete parts a through c.

a. Define the population of interest to the interviewers.

A. All people in the region who are over 18 years old.

B. Marriage status

C. The 93 million households in the region

D. The 39,000 households visited in the region

b. What variable is being measured?

A. The 93 million households in the region.

B. The 39,000 households visited in the region

C. All people in the region who are over 18 years old.

D. Marriage status

Is it quantitative or qualitative?

Qualitative

Quantitative

c. Is the problem of interest to the interviewers descriptive or inferential?

Descriptive

Inferential

20. The salaries of superstar professional athletes receive much attention in the media. The multimillion-dollar long-term contract is now commonplace among this elite group. Nevertheless, rarely does a season pass without negotiations between one or more of the players’ associations and team owners for additional salary and fringe benefits for all players in their particular sports. Complete parts a and b below.

a. If a players association wanted to support its argument for higher “average” salaries, which measure of central tendency do you think it should use? Why?

A. The players’ association would want to use the mode to support its argument for higher “average” salaries because the mode is the value that occurs most often. This is the preferred measure of center because it most accurately depicts the players’ salaries and would be most likely to result in a higher pay increase.

B. The players’ association would want to use the mean to support its argument for higher “average” salaries the mean is the average value of all salaries. This is the preferred measure of center because it most accurately depicts the players’ salaries and would be most likely to result in a higher pay increase.

C. The players’ association would want to use the median to support its argument for higher “average” salaries the median is the value at which half of the data values are higher than it. This is the preferred measure of center because it most accurately depicts the players’ salaries and would be most likely to result in a higher pay increase.

b. To refute the argument, which measure of central tendency should the owners apply to the player’ salaries?

A. To refute the argument, the owners should use the median because the median is the value at which half of the data values are higher than it. The median is affected by extreme values, so using the median would most likely result is a lower pay increase.

B. To refute the argument, the owners should use the mean because the mean is the average value of all the player’s salaries. The mean is affected by extreme values, so using the mean would most likely result in a lower pay increase.

C. To refute the argument, the owners should use the mode is the value that occurs most often. The mode is affected by extreme values, so using the mode would most likely result in a lower pay increase.