Conditions for Z-test
Z-test (or) Large sample test is used to compare the sample mean & population mean only when-
- Sample size is large (Sample size > 30)
- Population standard deviation or population variance is known
- Both conditions must be fulfilled — Correct Answer
- None
Explanation:
Correct Answer: Both conditions must be fulfilled
The Z-test requires both conditions to be satisfied simultaneously: (1) sample size > 30 AND (2) population standard deviation (or variance) is known.
Z-test vs T-test Comparison
| Feature | Z-test (Large Sample Test) | T-test (Small Sample Test) |
|---|---|---|
| Sample size | n > 30 | n < 30 |
| Population SD | Known | Unknown |
| Application | Compare sample mean with population mean | Compare sample mean with population mean |
| T-test types | — | Paired T-test and Unpaired T-test |
Other Statistical Tests
- F-test/ANOVA: Compare two variances OR more than two sample means.
- Chi-square test: Non-parametric; goodness of fit; test for independence; always positive.
📚 About this Topic — Animal Genetics & Breeding
This multiple choice question is from Animal Genetics & Breeding, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Genetics & Breeding to strengthen your preparation.
