Question 1

Which of the following best describes the difference between a population parameter and a sample statistic?

Accepted Answer

A population parameter is a numerical measurement describing a characteristic of the population, while a sample statistic describes a characteristic of a sample.

Question 2

A university wants to estimate the proportion of students who commute to campus. They randomly select 200 students from the entire student list and survey them. Which sampling method is being used?

Accepted Answer

Simple random sampling

Question 3

Which of the following is an example of response bias in a survey?

Accepted Answer

Survey participants give answers they believe are more socially acceptable rather than their true opinions.

Question 4

Suppose a company wants to check the accuracy of its accounting process. It divides all transactions into five groups based on transaction type and randomly selects 20 transactions from each group for review. What sampling method is this?

Accepted Answer

Stratified sampling

Question 5

Which of the following formulas correctly represents the population variance?

Accepted Answer

$$\$$sigma^2$$ = \frac{1}{N} \sum (x_i - \mu)^2$

Question 6

A researcher wants to survey employees in a large company. She randomly selects 10 departments and surveys every employee in those departments. Which sampling method is this?

Accepted Answer

Cluster sampling

Question 7

Which of the following best describes systematic sampling?

Accepted Answer

Selecting every $$kth $$individual from a list after a random start.

Question 8

A sample statistic is said to be unbiased if:

Accepted Answer

Its expected value equals the population parameter.

Question 9

Which of the following is NOT a potential source of bias in sample surveys?

Accepted Answer

Pilot survey bias

Question 10

Suppose a population consists of 1000 individuals. You want to select a sample of 50 using systematic sampling. What is the sampling interval $$k$$ you should use?

Accepted Answer

$$k = 20$$

Question 11

A company wants to estimate the average salary of its employees. It divides employees into management and non-management, then randomly samples from each group. This is an example of:

Accepted Answer

Stratified sampling

Question 12

Which of the following statements about cluster sampling is TRUE?

Accepted Answer

Clusters should be representative of the population as a whole.

Question 13

If a survey is conducted only among volunteers who choose to participate, which type of bias is most likely to occur?

Accepted Answer

Self-selection bias

Question 14

Which of the following is the correct formula for the sample standard deviation?

Accepted Answer

$$s = \sqrt{\frac{1}{n-1} \sum (x_i - \bar{x})^2$}$$

Question 15

A pilot survey is conducted before the main survey in order to:

Accepted Answer

Test the survey procedures and identify potential errors.

Question 16

Which of the following best describes multistage sampling?

Accepted Answer

Sampling that combines several sampling methods in stages.

Question 17

A researcher uses a table of random numbers to select individuals for a survey. This method is most closely associated with:

Accepted Answer

Simple random sampling

Question 18

Which of the following is a key advantage of stratified sampling over simple random sampling?

Accepted Answer

It ensures representation from all subgroups of the population.

Question 19

Suppose a survey is conducted to estimate the average commute time of employees in a city. The city is divided into neighborhoods, and a random sample of neighborhoods is selected. All employees in those neighborhoods are surveyed. Which sampling method is this?

Accepted Answer

Cluster sampling

Question 20

Which of the following statements about bias in sample surveys is correct?

Accepted Answer

Bias refers to systematic errors that lead to inaccurate estimates of population parameters.

Sampling Methods and Sample Surveys in Statistics

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