Z-test MCQs with Answers: Interview Questions

In this blog post, you can test your knowledge about Z-test, Z-statistics and related concepts through multiple choice questions (MCQs) and answers. Getting a good understanding of Z-tests, Z-statistics and Z-distribution is of utmost importance for data scientists at large. The following are key concepts around which the MCQs are posted:

• Z-score or Z-statistics concepts
• Estimation of population mean and proportion
• 1-sample Z-test for mean and proportion
• 2-samples Z-test for mean and proportion

Z-test Interview Questions Samples

The following is a list of interview questions that you would want to learn:

• What is Z-score? Explain with an example and formula.
• What are different types of Z-tests? Explain with formula and examples.
• What is difference between 1-sample and 2-samples Z-test for means? Explain with one example each and formula. 
• What is difference between 1-sample and 2-samples Z-test for proportions? Explain with one example each and formula.
• How do you estimate population mean at 95% confidence interval as a function of Z-score?
• How do you estimate population proportion at 95% confidence interval as a function of Z-score?
• What is standard error? How is it related to margin of error?
• When to use Z-test and when to use T-test?
• What is sampling distribution and how is it related to Z-test and Z-statistics?
• What is Z-distribution? How is this different from T-distribution?
• What is standard score? 
• How can Z-score be used to compare marks of two students in different classes?

Z-test MCQs Quiz: Questions & Answers

The following is a list of questions and answers aimed to test your knowledge of different types of Z-tests, Z-statistics, hypothesis testing etc.

 

#1. ______ is used when population standard deviation is unknown and the sample size is small?

Z-score

T-score

#2. Z-statistics can be used to estimate ________ proportion?

Population

Sample

#3. _______ will be used for estimating population mean for sample size lesser than 30

T-distribution

Z-distribution

#4. 2-sample Z-test can be used to perform hypothesis testing for ________?

Proportion

Both of the above

None of the above

Mean

#5. Margin of error can be defined as the function of ________

Both

None of the above

Z-statistics

T-statistics

#6. Margin of error can be defined as the function of ________

T-statistics

Z-statistics

Both

None of the above

#7. _______ will be used for estimating population mean for sample size lesser than 30

Z-distribution

T-distribution

#8. Z-score is used when _________ standard deviation is known?

Population

Sample

#9. Standard error is the ___________ of the ___________ in the sampling distribution?

Standard deviation, sample mean

Standard deviation, population mean

#10. Z-test can be used for __________?

None of the above

One-tailed test

Both of the above

Two-tailed test

#11. 1-sample Z-test can be used to perform hypothesis testing for ________?

Mean

Proportion

None of the above

Both of the above

#12. Margin of error can be defined as the function of ________

Z-statistics

None of the above

Both

T-statistics

#13. Estimating population mean with 95% confidence interval given a sample size of 10 would mean the value of T-score to be _______

2.262

3.25

2.821

#14. _______ can be used for hypothesis testing when the sample size is larger than 30

T-statistics

F-statistics

Z-statistics

#15. Z-statistics can be used to estimate ________ mean?

Sample

Population

#16. _______ will be used for estimating population mean for sample size greater than 30

Z-distribution

T-distribution

#17. _______ will be used for estimating population mean for sample size greater than 30

Z-distribution

T-distribution

#18. Standard error is _________ divided by the square root of ________?

Sample standard deviation, sample size

Population standard deviation, sample size

None of the above

Can be both

#19. Z-test can be used to perform hypothesis testing related to sample ________?

Both of the above

None of the above

Mean

Proportion

#20. Z-statistics can be used to estimate ________ proportion?

Sample

Population

#21. Z-test can be used for __________?

One-tailed test

None of the above

Both of the above

Two-tailed test

#22. 2-sample Z-test can be used to perform hypothesis testing for ________?

Mean

None of the above

Both of the above

Proportion

#23. Z-test can be used to perform hypothesis testing related to sample ________?

Mean

None of the above

Both of the above

Proportion

#24. _______ can be used for hypothesis testing when the sample size is larger than 30

T-statistics

Z-statistics

F-statistics

#25. Z-score is used when _________ standard deviation is known?

Sample

Population

#26. Standard error is _________ divided by the square root of ________?

Can be both

Population standard deviation, sample size

Sample standard deviation, sample size

None of the above

#27. Estimating population mean with 95% confidence interval would mean the value of Z-score to be _______

1.96

1.645

2.576

#28. 1-sample Z-test can be used to perform hypothesis testing for ________?

Mean

Both of the above

Proportion

None of the above

#29. Estimating population mean with 95% confidence interval would mean the value of Z-score to be _______

1.645

2.576

1.96

#30. Standard error is _________ divided by the square root of ________?

Can be both

None of the above

Population standard deviation, sample size

Sample standard deviation, sample size

#31. Standard error is the ___________ of the ___________ in the sampling distribution?

Standard deviation, sample mean

Standard deviation, population mean

#32. Z-statistics can be used to estimate ________ mean?

Population

Sample

#33. Z-score is used when _________ standard deviation is known?

Sample

Population

#34. ______ is used when population standard deviation is unknown and the sample size is small?

Z-score

T-score

#35. Estimating population mean with 95% confidence interval given a sample size of 10 would mean the value of T-score to be _______

3.25

2.821

2.262

#36. Standard error is the ___________ of the ___________ in the sampling distribution?

Standard deviation, population mean

Standard deviation, sample mean

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Ajitesh Kumar

I have been recently working in the area of Data analytics including Data Science and Machine Learning / Deep Learning. I am also passionate about different technologies including programming languages such as Java/JEE, Javascript, Python, R, Julia, etc, and technologies such as Blockchain, mobile computing, cloud-native technologies, application security, cloud computing platforms, big data, etc. I would love to connect with you on Linkedin.
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