Question 1

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience.
-The name of each contestant is written on a separate card, the cards are placed in a bag, and three names are
Picked from the bag.

Accepted Answer

This method is an example of random sampling because each contestant has an equal chance of being selected, and the selection is made randomly from the bag.

Question 2

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience.
-A pollster uses a computer to generate 500 random numbers, then interviews the voters corresponding to those
Numbers.

Accepted Answer

The use of computer-generated random numbers to select participants indicates the use of random sampling, where each member of the population has an equal chance of being selected.

Question 3

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience.
-An education researcher randomly selects 48 middle schools and interviews all the teachers at each school.

Accepted Answer

This is an example of cluster sampling because the researcher selects entire groups (in this case, schools) and then collects data from all members within those selected groups.

Question 4

Provide an appropriate response.
-A questionnaire is sent to 10,000 persons. 5000 responded to the questionnaire. 3000 of the respondents say that
"They love chocolate ice cream." We conclude that 60% of people love chocolate ice cream. What is wrong with
this survey?

Accepted Answer

The answer of Provide an appropriate response.
-A questionnaire is sent...

Question 5

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience.
-A researcher interviews 19 work colleagues who work in his building.

Accepted Answer

The researcher is using convenience sampling because they are selecting participants who are easily accessible to them (i.e., work colleagues in the same building), rather than using a method that ensures each member of a population has an equal chance of being included.

Question 6

Provide an appropriate response.
-You plan to make a survey of 200 people. The plan is to talk to every 10th person coming out of the school
library. Is there a problem with your plan?

Accepted Answer

The answer of Provide an appropriate response.
-You plan to make...

Question 7

Provide an appropriate response.
-The graph shows the increases in a certain expenditure over a four-year period. What is wrong with the graph?

Accepted Answer

The answer of Provide an appropriate response.
-The graph shows the...

Question 8

Provide an appropriate response.
-"38% of adults in the United States regularly visit a doctor." This conclusion was reached by a college student
after she had questioned 520 randomly selected members of her college. What is wrong with her survey?

Accepted Answer

The answer of Provide an appropriate response.
-"38% of adults in...

Question 9

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience.
-A tax auditor selects every 1000th income tax return that is received.

Accepted Answer

Systematic sampling is used here, as the tax auditor selects every 1000th income tax return, which is a methodical selection process.

Question 10

Provide an appropriate response.
-A political researcher wishes to gauge political sentiment regarding a proposed tax cut. He obtains a list of 1000 email addresses from an internet provider, uses a random number table to select a random sample of 100 of these addresses, emails the people in the sample and requests that they respond to his questions by email. Do you think that the group of people who respond is likely to be representative of all registered voters? Explain
your answer.

Accepted Answer

The answer of Provide an appropriate response.
-A political researcher wishes...

Question 11

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience.
-A sample consists of every 49th student from a group of 496 students.

Accepted Answer

This is an example of systematic sampling because it involves selecting members from a larger group at a regular interval (every 49th student), which is a characteristic of systematic sampling.

Question 12

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience.
-A market researcher selects 500 drivers under 30 years of age and 500 drivers over 30 years of age.

Accepted Answer

The market researcher is using stratified sampling by dividing the population into two distinct groups (drivers under 30 years of age and drivers over 30 years of age) and then sampling from each group. This ensures representation from each subgroup.

Question 13

Provide an appropriate response.
-"7 out of 10 dentists recommend Brand X toothpaste." This finding is based on the results of a survey of 10
randomly selected dentists. What is wrong with this survey?

Accepted Answer

The answer of Provide an appropriate response.
-"7 out of 10...

Question 14

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience.
-49, 34, and 48 students are selected from the Sophomore, Junior, and Senior classes with 496, 348, and 481
Students respectively.

Accepted Answer

Stratified sampling is used here because the population is divided into subgroups (Sophomore, Junior, and Senior classes) and samples are taken from each subgroup to ensure representation of the entire population.

Question 15

Provide an appropriate response.
-A college lecturer has devised a new method of teaching a particular mathematical concept and wishes to try out this teaching method on a representative sample of his students. There are 76 students in his class and he wishes to obtain a simple random sample of 25 of them. Describe a method he could use to obtain the sample.

Accepted Answer

The answer of Provide an appropriate response.
-A college lecturer has...

Question 16

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience.
-A market researcher selects 500 people from each of 10 cities.

Accepted Answer

The sampling method described is stratified sampling because the researcher selects a specific number of people (500) from each of the 10 cities, which are considered as strata.

Question 17

Provide an appropriate response.
-A researcher published this survey result: "74% of people would be willing to spend 10 percent more for energy
from a non-polluting source." The survey question was announced on a national radio show and 1200 listeners
responded by calling in. What is wrong with this survey?

Accepted Answer

The answer of Provide an appropriate response.
-A researcher published this...

Question 18

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience.
-To avoid working late, a quality control analyst simply inspects the first 100 items produced in a day.

Accepted Answer

This is an example of convenience sampling because the analyst is choosing the sample based on what is easiest or most convenient to sample, in this case, the first 100 items produced in a day.

Question 19

Provide an appropriate response.
-Identify four major flaws in the following: The host of a conservative talk show ran a survey by asking his
listeners to respond to the following question: "Do you think that environmental laws which restrict growth
should be weakened?" Twenty people responded, and the next day the talk show host announced that the
results of his survey suggested that 76% of Americans feel that environmental laws should be weakened.

Accepted Answer

The answer of Provide an appropriate response.
-Identify four major flaws...

Question 20

Answer the question.
-A concerned parent wants to determine the amount of time spent on the phone by her child's friends. Which
Sample is likely to bias the results of the study by reporting less than the actual time?

Accepted Answer

The answer of Answer the question.
-A concerned parent wants to...

Quiz 1: Speaking of Statistics

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience. -The name of each contestant is written on a separate card, the cards are placed in a bag, and three names are Picked from the bag.

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience. -A pollster uses a computer to generate 500 random numbers, then interviews the voters corresponding to those Numbers.

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience. -An education researcher randomly selects 48 middle schools and interviews all the teachers at each school.

Provide an appropriate response. -A questionnaire is sent to 10,000 persons. 5000 responded to the questionnaire. 3000 of the respondents say that "They love chocolate ice cream." We conclude that 60% of people love chocolate ice cream. What is wrong with this survey?

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience. -A researcher interviews 19 work colleagues who work in his building.

Provide an appropriate response. -You plan to make a survey of 200 people. The plan is to talk to every 10th person coming out of the school library. Is there a problem with your plan?

Provide an appropriate response. -The graph shows the increases in a certain expenditure over a four-year period. What is wrong with the graph?

Provide an appropriate response. -"38% of adults in the United States regularly visit a doctor." This conclusion was reached by a college student after she had questioned 520 randomly selected members of her college. What is wrong with her survey?

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience. -A tax auditor selects every 1000th income tax return that is received.

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience. -A sample consists of every 49th student from a group of 496 students.

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience. -A market researcher selects 500 drivers under 30 years of age and 500 drivers over 30 years of age.

Provide an appropriate response. -"7 out of 10 dentists recommend Brand X toothpaste." This finding is based on the results of a survey of 10 randomly selected dentists. What is wrong with this survey?

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience. -49, 34, and 48 students are selected from the Sophomore, Junior, and Senior classes with 496, 348, and 481 Students respectively.

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience. -A market researcher selects 500 people from each of 10 cities.

Identify which of these types of sampling is used: random, stratified, systematic, cluster, convenience. -To avoid working late, a quality control analyst simply inspects the first 100 items produced in a day.

Answer the question. -A concerned parent wants to determine the amount of time spent on the phone by her child's friends. Which Sample is likely to bias the results of the study by reporting less than the actual time?