A scientist suspects there is a positive correlation between the concentration of a certain nutrient in soil and the height of the plants grown in it.
He calculates the product moment correlation coefficient for a random sample of 12 plants and obtains r=0.468r = 0.468r=0.468.
Carry out a suitable test to investigate the scientist's suspicion at a 5% level of significance.
State clearly
316 exam-style questions on OCR A Level Maths 2.5 Statistical Hypothesis Testing, covering 2.5.1 The language of hypothesis testing, 2.5.2 Hypothesis test for a binomial proportion, 2.5.3 Inference and significance level, 2.5.4 Sample mean as a random variable (A-level only), 2.5.5 Hypothesis test for the mean of a normal distribution (A-level only), 2.5.6 Pearson's product-moment correlation coefficient, and 2.5.7 Hypothesis test using Pearson's coefficient (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.