A-level · Hypothesis testing

Hypothesis testing for zero correlationExam-style questions

Testing whether a population has any linear correlation by comparing the sample PMCC r against a critical value from tables — choosing one- or two-tailed hypotheses on ρ, and concluding in context.

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

DifficultyAllLevel 3Level 4Level 5
  1. 1
    A sample of n=10n = 10 gives a PMCC of r=0.72r = 0.72. Test, at the 5%5\% significance level, whether there is positive correlation in the population. The critical value is 0.54940.5494.
    Level 3 · 3 marksTry it
  2. 2
    A sample of n=12n = 12 gives r=−0.62r = -0.62. Test at the 5%5\% level whether there is correlation in the population. For this two-tailed test the critical value is 0.57600.5760.
    Level 3 · 3 marksTry it
  3. 3
    A sample of n=10n = 10 gives r=0.40r = 0.40. Test at the 5%5\% level whether there is positive correlation. The critical value is 0.54940.5494.
    Level 3 · 3 marksTry it
  4. 4
    For 55 pairs of data, ∑x=15\sum x = 15, ∑y=20\sum y = 20, ∑xy=69\sum xy = 69, ∑x2=55\sum x^2 = 55, ∑y2=90\sum y^2 = 90.
    (a) Show that r=0.900r = 0.900.
    (b) Test at the 5%5\% level for positive correlation. The critical value is 0.80540.8054.
    Level 3 · 5 marksTry it
  5. 5
    A sample of n=15n = 15 pairs gives a product moment correlation coefficient of r=0.52r = 0.52.

    Test, at the 5%5\% significance level, whether there is evidence of positive correlation in the population. The critical value for n=15n = 15 is 0.44090.4409. (4 marks)
    Level 3 · 4 marksTry it

8 more questions on hypothesis testing for zero correlation

Free with an account — just an email, no card. The whole bank, every mark scheme and worked solution.

Start free