| Exam Board | Edexcel |
|---|---|
| Module | S4 (Statistics 4) |
| Marks | 6 |
| Paper | Download PDF ↗ |
| Topic | F-test and chi-squared for variance |
| Type | F-test two variances hypothesis |
| Difficulty | Standard +0.3 This is a standard F-test for comparing two variances with straightforward application of the test procedure. While it requires knowledge of the F-distribution and hypothesis testing framework, it's a routine S4 question with clear setup, standard hypotheses, and direct calculation—slightly easier than average due to its textbook nature and minimal computational complexity. |
| Spec | 5.05c Hypothesis test: normal distribution for population mean |
The standard deviation of the length of a random sample of 8 fence posts produced by a timber yard was 8 mm. A second timber yard produced a random sample of 13 fence posts with a standard deviation of 14 mm.
\begin{enumerate}[label=(\alph*)]
\item Test, at the 10\% significance level, whether or not there is evidence that the lengths of fence posts produced by these timber yards differ in variability. State your hypotheses clearly. [5]
\item State an assumption you have made in order to carry out the test in part (a). [1]
\end{enumerate}
(Total 6 marks)
\hfill \mbox{\textit{Edexcel S4 Q2 [6]}}