Statistical inference — Question 1

QCAA 2024, Paper 1 · 1 mark

Q1 · 2024 · Technology-freeSimple familiar1 mark

QUESTION 1

Repeated random samples will be used to calculate a large number of 90% confidence intervals for a population mean

\mu

. Which statement best describes the possible outcomes?

(A)

Approximately 90% of the intervals will contain

\mu

(B)

More than 90% of the intervals will contain

\mu

(C)

Less than 90% of the intervals will contain

\mu

(D)

Exactly 90% of the intervals will contain

\mu

ABCD

Question linkOriginal paper

WORKED SOLUTION

Answer A

1 mark

ANSWER

Worked solution

A 90% confidence procedure has 90% long-run coverage: over a large number of repeated random samples, approximately 90% of the resulting intervals contain the fixed population mean

\mu

Selects option A.

[1 mark]

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

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