7. Determine whether the underlined value is a parameter or a statistic. One of the greatest baseball hitters of all time has a career batting average

of 0.366.

Is the value a parameter or a​ statistic?

1. The value is a parameter because the career at-bats of a baseball player are a population.
2. The value is a parameter because the career at-bats of a baseball player are a sample.
3. The value is a statistic because the career at-bats of a baseball player are a population.
4. The value is a statistic because the career at-bats of a baseball player are a sample.

 

8. Determine whether the underlined numerical value is a parameter or a statistic. Explain your reasoning In a poll of a sample of 12,000 adults in a certain city, 12% said they left for work before 6 a.m.

Choose the correct answer below.

1. Statistic​, because the data set of all adults in a city is a population.
2. Parameter​, because the data set of all adults in a city is a sample.
3. Statistic​, because the data set of a sample of 12,000 adults in a city is a sample.
4. Parameter​, because the data set of a sample of 12,000 adults in a city is a population.
5. Statistic​, because the data set of a sample of 12,000 adults in a city is a population.
6. Parameter​, because the data set of all adults in a city is a population.
7. Parameter​, because the data set of a sample of 12,000 adults in a city is a sample.
8. Statistic​, because the data set of all adults in a city is a sample.

 

9.  Determine whether the variable is qualitative or quantitative.  Favorite color

Is the variable qualitative or​ quantitative?

1. The variable is quantitative because it is an attribute characteristic.
2. The variable is qualitative because it is an attribute characteristic.
3. The variable is quantitative because it is a numerical measure.
4. The variable is qualitative because it is a numerical measure.

 

10.  Determine whether the variable is qualitative or quantitative.  Model of car driven

Is the variable qualitative or​ quantitative?

1. The variable is quantitative because it is an attribute characteristic.
2. The variable is quantitative because it is a numerical measure.
3. The variable is qualitative because it is a numerical measure.
4. The variable is qualitative because it is an attribute characteristic.

 

 

11.  Determine whether the variable is qualitative or quantitative.  Distance in miles to nearest outdoor stadium

Is the variable qualitative or​ quantitative?

1. The variable is quantitative because it is an attribute characteristic.
2. The variable is quantitative because it is a numerical measure.
3. The variable is qualitative because it is an attribute characteristic.
4. The variable is qualitative because it is a numerical measure.

 

12.  Determine whether the variable is qualitative or quantitative. Number of cars owned

Is the variable qualitative or​ quantitative?

1. The variable is quantitative because it is a numerical measure.
2. The variable is qualitative because it is a numerical measure.
3. The variable is quantitative because it is an attribute characteristic.
4. The variable is qualitative because it is an attribute characteristic.

 

13.  Determine whether the quantitative variable is discrete or continuous.  Number of cars owned

Is the variable discrete or​ continuous?

1. The variable is continuous because it is countable.
2. The variable is discrete because it is countable.
3. The variable is discrete because it is not countable.
4. The variable is continuous because it is not countable.

 

14.  Determine whether the quantitative variable is discrete or continuous.  Number of pieces of lumber used to make a deck

Is the variable discrete or​ continuous?

1. The variable is continuous because it is not countable.
2. The variable is discrete because it is countable.
3. The variable is discrete because it is not countable.
4. The variable is continuous because it is countable.

 

15.  Determine whether the quantitative variable is discrete or continuous.  Temperature on a randomly selected day in your home town

Is the variable discrete or​ continuous?

1. The variable is discrete because it is countable.
2. The variable is discrete because it is not countable.
3. The variable is continuous because it is not countable.
4. The variable is continuous because it is countable.

 

16.  Determine whether the quantitative variable is discrete or continuous.  Length of a nail.

Is the variable discrete or​ continuous?

1. The variable is continuous because it is countable.
2. The variable is discrete because it is not countable.
3. The variable is continuous because it is not countable.
4. The variable is discrete because it is countable.

 

17.  Determine the level of measurement of the variable. The rankings of songs in the top 100

Choose the correct level of measurement.

1. Ratio
2. Interval
3. Ordinal
4. Nominal

 

18.  Determine the level of measurement of the variable below.  Year of birth of college students

Choose the correct answer below.

1. Nominal
2. Ratio
3. Ordinal
4. Interval

 

19.  Determine the level of measurement of the variable below.  Movie ratings of one star through five stars

Choose the correct answer below.

1. Ordinal
2. Ratio
3. Interval
4. Nominal

 

20.  Determine the level of measurement of the variable below.  Nation of origin

Choose the correct answer below.

1. Ordinal
2. Interval
3. Nominal
4. Ratio

 

21.  Determine the level of measurement of the variable.  Monthly temperatures: 64° F, 70° F, 76° F, 82° F, and 88° F

Choose the correct answer below.

1. Ordinal
2. Nominal
3. Interval
4. Ratio

 

22.  A polling organization contacts 1977 adults who are 20 to 90 years of age and live in Europe and asks whether or not they had voted in the last federal election.

What is the population in the​ study?

1. Adults who are 20 to 90 years of age.
2. Adults who are 20 to 90 years of age and have voted.
3. Adults who are 20 to 90 years of age and live in Europe.
4. Adults who are 20 to 90 years of age and live in Europe and have voted.

 

What is the sample in the​ study?

1. Adults who are 20 to 90 years of age.
2. The 1977 adults who are 20 to 90 years of age and live in Europe.
3. The 1977 adults who are 20 to 90 years of age and have voted.
4. Adults who are 20 to 90 years of age and live in Europe.

 

23. A​ quality-control manager randomly selects 90 bottles of apple juice that were filled on December 19 to assess the calibration of the filling machine.

What is the population in the​ study?

1. All bottles of apple juice produced in the plant in the given year.
2. The 90 bottles of apple juice selected in the plant on December 19.
3. The 90 bottles of apple juice selected in the plant.
4. All bottles of apple juice produced in the plant on December 19.

 

What is the sample in the​ study?

1. The 90 bottles of apple juice selected in the plant in December.
2. All bottles of apple juice produced in the plant in the given year.
3. All bottles of apple juice produced in the plant on December 19.
4. The 90 bottles of apple juice selected in the plant on December 19.

 

24.  The data on the right relate to characteristics of​ high-definition televisions A through E. Identify the​ individuals, variables, and data corresponding to the variables. Determine whether each variable is​ qualitative, continuous, or discrete.

What are the individuals being​ studied?

1. Plasma and projection widescreen​ high-definition televisions.
2. Television setups that include more than 100 channels.
3. Televisions with screen sizes between 40 in and 60 in.
4. The​ high-definition television setups A through E.

 

What are the variables and their corresponding data being​ studied?

1. Size ​(43​, 57​, 59​, 53​, 40​) and number of channels available ​(300​, 114​, 423​, 269​, 290​)
2. Setup ​(A, B,​ C, D,​ E), size ​(43​, 57​, 59​, 53​, 40​), screen type ​(Projection​, Projection, Plasma​,Projection​, Plasma​), and number of channels available ​(300​, 114​, 423​, 269​, 290​)
3. Size ​(43​, 57​, 59​, 53​, 40​), screen type ​(Projection​, Projection​, Plasma​, Projection, Plasma​), and number of channels available ​(300​, 114​, 423​, 269​, 290​)

 

Determine whether each variable is​ qualitative, continuous, or discrete.

Size is a ________ variable. Screen type is a __________variable.

Number of channels available is a ________variable.

 

25.  A study conducted by researchers was designed​ “to determine if application of duct tape is as effective as cryotherapy in the treatment of common​ warts.” The researchers randomly divided 54 patients into two groups. The 27 patients in group 1 had their warts treated by applying duct tape. The 27 patients in group 2 had their warts treated by cryotherapy. Once the treatments were​ complete, it was determined that 70​% of the patients in group 1 and 52​% of the patients in group 2 had complete resolution of their warts. The researchers concluded that duct tape is significantly more effective in treating warts than cryotherapy. Complete parts​ (a) through​ (d) below.

​(a) What is the research​ objective?

1. To determine if cryotherapy is effective in the treatment of warts
2. To determine if duct tape is as effective as cryotherapy in the treatment of warts
3. To determine if duct tape is effective in the treatment of warts
4. To determine if cryotherapy is as effective as duct tape in the treatment of warts

​

(b) What is the population being​ studied? What is the​ sample?

What is the population being​ studied?

1. The 27 patients in group 2
2. The 54 patients with warts
3. All people who have warts
4. The 27 patients in group 1
5. The total number of patients with complete resolution of their warts

 

What is the​ sample?

1. The 27 patients in group 2
2. All people who have warts
3. The total number of patients with complete resolution of their warts
4. The 54 patients with warts
5. The 27 patients in group 1

​

(c) What are the descriptive​ statistics?

1. There are 54 patients with warts.
2. There are 27 patients in group 1 and 27 patients in group 2.
3. 70​% of all patients treated with duct tape and 52​% of all patients treated with cryotherapy will have resolution of their warts.
4. 70​% of patients in group 1 and 52​% of patients in group 2 had resolution of their warts.

 

​(d) What is the conclusion of the​ study?

1. Duct tape is significantly more effective than cryotherapy in treating warts.
2. Duct tape is effective in the treatment of warts.
3. Cryotherapy is significantly more effective than duct tape in treating warts.
4. Duct tape and cryotherapy are equally effective in treating warts.
5. Cryotherapy is effective in the treatment of warts.

 

26.  Explain what is meant when it is said that​ “data vary”. How does the variability affect the results of statistical​ analysis?

Choose the correct answer below.

1. Saying​ “data vary” means that examining different types of subjects will yield different​ data, such as examining a person and examining a car. Because data​ vary, it is impossible to compare different types of​ subjects, such as comparing people and cars.
2. Saying​ “data vary” means that observations can be measured with fractions or decimals instead of only integers. Because data​ vary, it is important to make sure to accurately account for fractional observations.
3. Saying​ “data vary” means that the values of the variable change from individual to individual. In​ addition, certain variables can change over time for certain individuals. Because data​ vary, two different statistical analysis of the same variable can lead to different results.
4. Saying​ “data vary” means that the values of the variable change every time they are observed. Because data​ vary, each statistical analysis of a given variable will lead to different results.

 

27.  Are the following statements true or​ false? Justify your answers. Complete parts​ (a) through​ (c) below. ​(This is a reading assessment question. Be certain of your answer because you only get one attempt on this​ question.)

​(a) In​ statistics, results are always reported with​ 100% certainty. Choose the correct answer below.

1. True. Statistics is the science of​ collecting, organizing,​ summarizing, and analyzing information to draw conclusions or answer questions. Since it is a​ science, results are always reported with​ 100% certainty.
2. True. Statistics would not be useful if they were not presented with​ 100% certainty. Statistics is a form of​ mathematics, which means that as long as correct procedures are​ used, all results must be correct.
3. False. In​ statistics, results are always reported with​ 100% certainty only when discrete variables are measured. Results cannot be reported with​ 100% certainty when continuous variables are measured.
4. False. In​ statistics, results are not reported with​ 100% certainty. Because statistical studies draw on​ samples, and because there is variation within​ groups, results cannot be reported with​ 100% certainty.

 

​(b) Statistical studies are not concerned with understanding the sources of variability in​ data, only with describing the variability in the data. Choose the correct answer below.

1. False. Statistical studies are concerned with neither understanding the sources of variability in data nor describing the variability in the data. Finding measures of the middle and trends are the only research objectives in statistical studies.
2. False. Statistical studies are concerned with both describing the variability in the data and understanding the sources of variability in data. Understanding the sources allows researchers to control it and reach better conclusions.
3. False. Statistical studies are not concerned with describing the variability in the​ data, only with understanding the sources of variability in the data. Understanding the sources allows researchers to determine what statistical methods to use in their studies.
4. True. Statistical studies are not concerned with understanding the sources of variability in​ data, only with describing the variability in the data. Descriptive statistics help researchers determine the type of statistical methods to use in their research.

​

(c) Suppose three different individuals conduct the same statistical​ study, such as estimating the average commute time of students at a college. It is possible that all three studies end up with different results. Choose the correct answer below.

1. True. If at least two of the individuals made different errors in their​ studies, then it is possible that all three studies end up with different results. This is the only way for all three studies to end up with different results.
2. False. Only two results are possible for any statistical study.​ Therefore, if all three individuals conduct the same statistical​ study, at least two of the three individuals must obtain matching results.
3. False. Statistics is a form of​ mathematics, which means that as long as correct procedures are​ used, all studies should obtain the same​ results, even if different studies used different procedures.
4. True. Statistical studies typically look at samples rather than entire populations. Since each study is likely to draw different​ samples, it is quite possible that each study ends up with different​ results, due to variability in the data.