For positive variables x x\,x and yyy, the correlation coefficient between x x\,x and log10y\log_{10}ylog10y is 0.980. The regression line is log10y=2.60+0.127x\log_{10}y=2.60+0.127xlog10y=2.60+0.127x.
Explain why the value 0.980 supports an exponential model for y y\,y in terms of xxx.
Find the model in the form y=abxy=ab^xy=abx, giving a a\,a and b b\,b to 3 significant figures.
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.