Statistical inference — Question 5

QCAA 2023, Paper 1 · 1 mark

Q5 · 2023 · Technology-freeSimple familiar1 mark

QUESTION 5

A confidence interval for a parameter is a range of values within which the

(A)

sample estimate of the parameter always lies.

(B)

sample estimate of the parameter never lies.

(C)

parameter always lies.

(D)

parameter never lies.

ABCD

Question linkOriginal paper

WORKED SOLUTION

Answer A

1 mark

ANSWER

Worked solution

A standard confidence interval is constructed around the sample estimate, so that estimate lies within the interval. The unknown population parameter is not guaranteed to lie in any particular realised interval.

Selects option A.

[1 mark]

Worked explanation by QCE Vault; correct option verified against the QCAA answer key.

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