A-level · Hypothesis testing

Setting up a hypothesis testExam-style questions

The language and structure of a binomial hypothesis test: the population proportion p, the null hypothesis H0 : p = p0 and the alternative hypothesis H1, deciding between a one-tailed (p < p0 or p > p0) and a two-tailed (p ≠ p0) test from the wording, the test statistic X ~ B(n, p0) under H0, and what the significance level means.

9 questions · A-level level · mark scheme and worked solution on each · no sign-up to try

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  1. 1
    A coin is suspected of being biased (in either direction). It is tossed 3030 times to test this. Write down suitable hypotheses for a test of the probability pp of heads.
    Level 3 · 2 marksTry it
  2. 2
    A treatment normally succeeds for 40%40\% of patients. A trial on 2525 patients is run to test whether a new version has a lower success rate. State the hypotheses and the distribution of the test statistic under H0H_0.
    Level 3 · 2 marksTry it
  3. 3
    Explain why the alternative hypothesis H1:p>0.2H_1: p > 0.2 leads to a one-tailed test, whereas H1:p≠0.2H_1: p \ne 0.2 leads to a two-tailed test.
    Level 3 · 2 marksTry it
  4. 4
    A spinner should land on red 14\tfrac14 of the time. In 4040 spins it lands on red 1616 times. A test is carried out to see whether red is more likely than it should be. Write down the hypotheses and the distribution of the test statistic under H0H_0, and state the observed value.
    Level 3 · 3 marksTry it