Stats Chapter 1

A study was done to determine the age, number of times per week, and the duration (amount of time) of residents using a local park in Toronto. The first house in the neighborhood around the park was selected randomly and then every eighth house in the neighborhood around the park was interviewed. The sampling method was:

systematic

stratified

cluster

simple random

systematic

The heights of everyone in the class

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Qualitative

Quantitative, Discrete

Quantitative, Continuous

Quantitative, Continuous

The number of books you own

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Qualitative

Quantitative, Discrete

Quantitative, Continuous

Quantitative, Discrete

The type of phone you own

\
Qualitative

Quantitative, Discrete

Quantitative, Continuous

Qualitative

The distance from your home to school

\
Qualitative

Quantitative, Discrete

Quantitative, Continuous

Quantitative, Continuous

The number of courses you have gotten A's in

\
Qualitative

Quantitative, Discrete

Quantitative, Continuous

Quantitative, Discrete

The number of years that the average temperature was above 25 degrees

\
Qualitative

Quantitative, Discrete

Quantitative, Continuous

Quantitative, Discrete

The city you were born in

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Qualitative

Quantitative, Discrete

Quantitative, Continuous

Qualitative

"Number of times per week" is what type of data?

\
quantitative, discrete

qualitative, continuous

quantitative, continuous

qualitative, discrete

Quantitative, Discrete

Which one of the following variables is not qualitative?

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Age of a person

Gender of a person

Choice of true or false on a test

marital status of a person

Age of a person

A study was done to compare the lung capacity of coal miners to the lung capacity of farm workers. The researcher studied 200 workers of each type. Other factors that might affect lung capacity are smoking habits and exercise habits. The smoking habits of the two worker types are similar, but the coal miners generally exercise less than the farm workers.

Which of the following might interfere with the results of the study? (called the confounding variable)

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occupation

lung capacity

exercise

smoking or not

exercise

A study was done to compare the lung capacity of coal miners to the lung capacity of farm workers. The researcher studied 200 workers of each type. Other factors that might affect lung capacity are smoking habits and exercise habits. The smoking habits of the two worker types are similar, but the coal miners generally exercise less than the farm workers.

Which of the following is the sample  in this study?

\
 all coal miners

all farm workers

all coal miners and farm workers

200 coal miners and 200 farm workers

200 coal miners and 200 farm workers

A study was done to compare the lung capacity of coal miners to the lung capacity of farm workers. The researcher studied 200 workers of each type. Other factors that might affect lung capacity are smoking habits and exercise habits. The smoking habits of the two worker types are similar, but the coal miners generally exercise less than the farm workers.

Which of the following is a response variable in this study?

\
exercise

smoking or not

lung capacity

occupation

lung capacity

A study was done to compare the lung capacity of coal miners to the lung capacity of farm workers. The researcher studied 200 workers of each type. Other factors that might affect lung capacity are smoking habits and exercise habits. The smoking habits of the two worker types are similar, but the coal miners generally exercise less than the farm workers.

Which of the following is the population  in this study?

\
 all coal miners

all farm workers

200 coal miners and 200 farm workers

all coal miners and farm workers

all coal miners and farm workers

A study was done to compare the lung capacity of coal miners to the lung capacity of farm workers. The researcher studied 200 workers of each type. Other factors that might affect lung capacity are smoking habits and exercise habits. The smoking habits of the two worker types are similar, but the coal miners generally exercise less than the farm workers.

Which of the following is the explanatory variable in this study?

\
occupation

smoking or not

lung capacity

exercise

occupation

The shoe size was determined for all female students in a class. 

What proportion of the students have size 8 or 8.5 shoe size?

Question 7 options:

0.85

0.7

0.3

1.2

0.3

The sum of relative frequencies will always be

Question 8 options:

1

different depending on the data

the total number of outcomes

between 0 and 1

1

The sum of frequencies will always be 

Question 6 options:

between 0 and 1

different depending on the data

1

the total number of outcomes

the total number of outcomes

The relative frequency is computed by

Question 5 options:

dividing the frequency by the midpoint

dividing the midpoint by the sample size

dividing the sample size by the frequency

dividing the frequency by the sample size

dividing the frequency by the sample size

The shoe size was determined for all female students in a class.

What proportion of the students have size 8 or more shoe size?

Question 4 options:

0.5

1

0.6

0.7

0.6

The shoe size was determined for all female students in a class. 

What proportion of the students have size 8 or less shoe size?

Question 3 options:

0.1

0.5

1.2

0.7

0.5

The shoe size was determined for all female students in a class.

What proportion of the students have size 11  shoe size?

Question 1 options:

can't answer

1

0

0.95

0

A cumulative relative frequency distribution shows

Question 2 options:

the total of the relative frequencies before the current row

the total of the relative frequencies before and including the current row

the total of the relative frequencies after the current row

the total of the relative frequencies before and including the current row

All samples lead to a good prediction about an entire population.

False

To find out what the preferred juice is, wait outside the cafeteria and ask every 4th person leaving to name their favourite flavour until you get 25 responses is an example of…

Simple Random Sampling

Convenience Sampling

Systematic Sample

Stratified Random Sample

Systematic Sample

To study the amount of time students spend doing homework each day, use a random number generator to select 25 students from the student enrollment database to survey.

Convenience Sampling

Systematic Sample

Simple Random Sampling

Stratified Random Sample

Simple Random Sampling

To determine the average number of students who study at the library,  the first 25 students who arrive to the library are asked their if they study there.  This is a good representative sample?

False

To study the amount of time students spend doing homework each day, Randomly select 4 classrooms and survey everyone in those rooms.

Simple Random Sampling

Cluster Sampling

Stratified Random Sample

Systematic Sample

Cluster Sampling

A Sample of 100 undergrad San Jose State students is taken by organizing the students names by classification (freshmen, sophomore, junior and senior) and then selecting 25 students from each.

Stratified

A random number generator is used to select a student from the alphabetical listing of all undergrads students in the fall semester. Every 50th student is chosen until 75 students are included in the sample

Systemic

A completely random method is used to select 75 students. Each undergrad student in the fall semester has the same probability of being chosen at any stage of the sampling process.

Simple random

The freshmen, sophomore, junior, and senior years are numbered 1;2;3;4 respectively. A random number generator is used to pick 2 of those years/groups. All students in those two years are in the sample.

Cluster

An admin assistant is asked to stand in front of the library on Wednesday and ask the first 100 undergrad students he encounters what they paid for tuition the Fall semester. Those 100 are the sample.

Convenience

Two possible wordings for a questionnaire on gun control are as follow:

I. The United States has the highest rate of murder by handguns among all countries. Most of these murders are known to be crimes of passion or crimes provoked by anger between acquaintances. Are you in favor of a 7- day cooling-off period between the filing of an application to purchase a handgun and the resulting sale?

II. The United States has one of the highest violent crime rates among all countries. Many people want to keep handguns in their homes for self-protection. Are you in favor of a 7-day waiting period between the filing of an application to purchase a needed handgun and the resulting sale?

One of these questions showed that 25% of the population favored a 7-day waiting period between application for purchase of a handgun and the resulting sale, while the other question showed that 70% of the population favored the waiting period. Which produced which result and why?

Question 1 options:

The first question probably showed 25% and the second question 70% because of a placebo effect due to the wording of the questions.

The first question probably showed 70% and the second question 25% because of the lack of randomization in the choice of pro-gun and anti-gun subjects as evidenced by the wording of the questions.

The first question probably showed 25% and the second question 70% because of response bias due to the wording of the questions.

The first question probably showed 70% and the second question 25% because of the lack of a control group.

The first question probably showed 70% and the second question 25% because of response bias due to the wording of the questions.

The first question probably showed 70% and the second question 25% because of response bias due to the wording of the questions.

The CRA decides to audit 26 companies.  The auditor lists all the companies that start with A, assigns each a number, and used a random number generator to pick one of the numbers and thus one company.  The auditor does the same for all letters of the alphabet.  Which of the following are true?  Select all that apply.

Question 2 options:

This is an example of stratified sampling

Each company has an equal probability of being audited

This is a simple random sample

The procedure makes use of chance.

This is an example of stratified sampling

The procedure makes use of chance.