Exercise · ZW-RANDOM-SAMPLE-006 · ★☆☆ Basic
A random sample of the students of a school is wanted. Which procedure comes closest to that ideal?
Choose one option.
Show answer
- A. Draw each student at random and separately from the complete list
Explanation
Drawing from the complete list gives every student the same chance and choices that do not influence each other. The other methods bring in bias or dependence.
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.
\[X_1,\dots,X_n\ \text{independent and identically distributed}\]
More practice problems: random sample
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- ZW-RANDOM-SAMPLE-008 If X_1,dots,X_n is a random sample, what holds for P(X_1≤ a,\ X_2≤ a)?
- ZW-RANDOM-SAMPLE-009 The heights of 3 siblings are called a random sample of the adult population. What goes wrong?