Exercise · ZW-RANDOM-SAMPLE-003 · ★☆☆ Basic
Which two properties define a random sample \(X_1,\dots,X_n\)?
Choose one option.
Show answer
- D. They are independent and have the same distribution
Explanation
The two conditions are independence and identical distribution (i.i.d.). Being equal or dependent is not required.
Review the concept: Random sample
A random sample of size \(n\) is a set of \(n\) independent random variables \(X_i\), all with the same distribution, that represent \(n\) observations from a population.
\[X_1,\dots,X_n\ \text{independent and identically distributed}\]
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