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-score is used when _________ standard deviation is known?

Sample

Population

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

Z-distribution

T-distribution

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

Two-tailed test

None of the above

Both of the above

One-tailed test

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

Z-statistics

T-statistics

F-statistics

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

Standard deviation, population mean

Standard deviation, sample mean

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

Both of the above

Mean

None of the above

Proportion

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

T-score

Z-score

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

2.262

2.821

3.25

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

Standard deviation, sample mean

Standard deviation, population mean

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

Both

Z-statistics

None of the above

T-statistics

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

Sample

Population

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

Standard deviation, sample mean

Standard deviation, population mean

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

Sample

Population

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

Both of the above

Proportion

Mean

None of the above

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

1.96

2.576

1.645

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

Sample

Population

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

Can be both

Sample standard deviation, sample size

Population standard deviation, sample size

None of the above

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

Population

Sample

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

Z-distribution

T-distribution

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

None of the above

Both

Z-statistics

T-statistics

#22. 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

#23. 1-sample Z-test can be used to perform hypothesis testing for ________?

None of the above

Mean

Both of the above

Proportion

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

Population

Sample

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

Two-tailed test

One-tailed test

Both of the above

None of the above

#26. 2-sample Z-test can be used to perform hypothesis testing for ________?

Both of the above

Proportion

Mean

None of the above

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

2.821

2.262

3.25

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

Z-statistics

Both

T-statistics

None of the above

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

Z-distribution

T-distribution

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

Z-distribution

T-distribution

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

Sample standard deviation, sample size

None of the above

Population standard deviation, sample size

Can be both

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

T-statistics

Z-statistics

F-statistics

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

2.576

1.645

1.96

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

Population

Sample

#35. 2-sample Z-test can be used to perform hypothesis testing for ________?

Both of the above

Proportion

None of the above

Mean

#36. 1-sample Z-test can be used to perform hypothesis testing for ________?

None of the above

Proportion

Both of the above

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 and BI. I would love to connect with you on Linkedin.
Check out my books titled as Designing Decisions, and First Principles Thinking.

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