OCR S1 2006 June — Question 1

Exam BoardOCR
ModuleS1 (Statistics 1)
Year2006
SessionJune
TopicLinear regression
TypeFind means from regression lines

1 Some observations of bivariate data were made and the equations of the two regression lines were found to be as follows. $$\begin{array} { c c } y \text { on } x : & y = - 0.6 x + 13.0
x \text { on } y : & x = - 1.6 y + 21.0 \end{array}$$
  1. State, with a reason, whether the correlation between \(x\) and \(y\) is negative or positive.
  2. Neither variable is controlled. Calculate an estimate of the value of \(x\) when \(y = 7.0\).
  3. Find the values of \(\bar { x }\) and \(\bar { y }\).