An environmental scientist studied the relationship between the daily average temperature, xxx (in ∘C^{\circ}\text{C}∘C), and the daily electricity consumption, yyy (in MWh), for a small town over 15 days in summer. The following summary statistics were calculated:
Sxx=450.4Syy=1240.2Sxy=652.8 S_{xx} = 450.4 \quad S_{yy} = 1240.2 \quad S_{xy} = 652.8 Sxx=450.4Syy=1240.2Sxy=652.8Calculate the product moment correlation coefficient (PMCC) for these data.
Interpret the value of the PMCC in the context of the study.
A student later coded the data by multiplying the temperature figures by 1.8 and adding 32 (to convert to Fahrenheit). Write down the value of the PMCC calculated using the coded data.
202 exam-style questions on Edexcel A Level Maths Regression, Correlation and Hypothesis Testing, covering 1.1 Exponential Models, 1.2 Measuring Correlation, and 1.3 Hypothesis Testing for Zero Correlation. Each one has a worked solution and a mark scheme showing where the marks go.