An oceanographic researcher investigates the relationship between the water depth, ddd (in metres), and the dissolved oxygen concentration, ccc (in mg/L), at 22 specific sites along a vertical transect. The following summary statistics were obtained from the collected data:
Sdd=18240Scc=64.8Sdc=−846.5 S_{dd} = 18240 \quad S_{cc} = 64.8 \quad S_{dc} = -846.5 Sdd=18240Scc=64.8Sdc=−846.5Calculate the product moment correlation coefficient (rrr) for these data, giving your answer to 3 significant figures.
Interpret your value of rrr in the context of the investigation.
The researcher decides to express the depth in feet (fff) and the oxygen concentration in grams per cubic metre (ggg), using the coding f=3.28d+15f = 3.28d + 15f=3.28d+15 and g=1.0cg = 1.0cg=1.0c. State the value of the PMCC for the coded data.
355 exam-style questions on OCR (MEI) A Level Maths 2.5 Statistical Hypothesis Testing, covering 2.5.1 Process and language of hypothesis testing, 2.5.2 When to apply 1-tail and 2-tail tests, 2.5.3 Significance level and incorrect rejection, 2.5.4 Null and alternative hypotheses (binomial), 2.5.5 Conduct a binomial hypothesis test, 2.5.6 Critical and acceptance regions (binomial), 2.5.7 Distribution of the sample mean (A-level only), 2.5.8 Hypothesis test for a single mean (A-level only), 2.5.9 Critical and acceptance regions (mean) (A-level only), 2.5.10 Correlation as closeness to a straight line (A-level only), 2.5.11 Inference using a correlation coefficient (A-level only), and 2.5 Statistical Hypothesis Testing. Each one has a worked solution and a mark scheme showing where the marks go.