| Exam Board | Edexcel |
|---|---|
| Module | S1 (Statistics 1) |
| Year | 2001 |
| Session | June |
| Marks | 5 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Bivariate data |
| Type | Calculate summary statistics (Sxx, Syy, Sxy) |
| Difficulty | Easy -1.2 This is a straightforward computational question requiring direct application of standard formulas (Sxx = Σx² - (Σx)²/n and PMCC = Sxy/√(SxxSyy)). All necessary values are provided, requiring only substitution and arithmetic with no conceptual insight or problem-solving beyond formula recall. |
| Spec | 2.02c Scatter diagrams and regression lines2.02d Informal interpretation of correlation |
2. On a particular day in summer 1993 at 0800 hours the height above sea level, $x$ metres, and the temperature, $y ^ { \circ } \mathrm { C }$, were recorded in 10 Mediterranean towns. The following summary statistics were calculated from the results.
$$\Sigma x = 7300 , \Sigma x ^ { 2 } = 6599600 , S _ { x y } = - 13060 , S _ { y y } = 140.9 .$$
\begin{enumerate}[label=(\alph*)]
\item Find $S _ { x x }$.
\item Calculate, to 3 significant figures, the product moment correlation coefficient between $x$ and $y$.
\item Give an interpretation of your coefficient.
\end{enumerate}
\hfill \mbox{\textit{Edexcel S1 2001 Q2 [5]}}