Chris is investigating the relationship between the length of time an employee has worked at his company, x x\,x years, and the amount of time it takes them to complete a task, y y\,y hours.
Chris records the time it takes 12 employees to complete the task and finds the product moment correlation coefficient between the length of time the employee has worked at the company and the time taken to complete the task to be -0.47
Chris codes the data using the coding m=log10xm = \log_{10}xm=log10x and n=log10yn = \log_{10}yn=log10y and obtains the model n=1−0.5mn = 1 - 0.5mn=1−0.5m
Show that the relationship between x x\,x and y y\,y can be written in the form y=axby = ax^by=axb where a a\,a and b b\,b are constants to be found.
340 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.