Exercise · ZW-ESTIMATOR-001 · ★☆☆ Basic
With the sample \(4,\ 8,\ 6,\ 10\), \(\bar X\) is used to estimate \(\mu\). What estimate is obtained?
Choose one option.
Show answer
- B. \(7\)
Explanation
The estimate is \(\bar x=(4+8+6+10)/4=7\). Dividing by \(n\) is what turns the sum into an average.
Review the concept: Estimator
An estimator \(\hat\theta\) is a rule \(T\), a function of the random sample \(X_i\), that produces a value used to approximate an unknown population parameter \(\theta\).
\[\hat\theta=T(X_1,\dots,X_n)\]
More practice problems: estimator
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- ZW-ESTIMATOR-009 If μ=3 and hatμ=2bar X is used, what is the bias?