| Exam Board | Edexcel |
|---|---|
| Module | S4 (Statistics 4) |
| Marks | 9 |
| Paper | Download PDF ↗ |
| Topic | T-tests (unknown variance) |
| Type | Paired sample t-test |
| Difficulty | Standard +0.3 This is a straightforward application of a paired t-test with clear data provided. Students need to calculate differences, find mean and standard deviation, compute the test statistic, and compare to critical values. While it requires multiple computational steps (8 marks), it's a standard textbook procedure with no conceptual challenges or novel problem-solving required. Slightly easier than average due to being a routine statistical test application. |
| Spec | 5.05c Hypothesis test: normal distribution for population mean |
A medical student is investigating two methods of taking a person's blood pressure. He takes a random sample of 10 people and measures their blood pressure using an arm cuff and a finger monitor. The table below shows the blood pressure for each person, measured by each method.
\includegraphics{figure_1}
\begin{enumerate}[label=(\alph*)]
\item Use a paired $t$-test to determine, at the 10\% level of significance, whether or not there is a difference in the mean blood pressure measured using the two methods. State your hypotheses clearly. [8]
\item State an assumption about the underlying distribution of measured blood pressure required for this test. [1]
\end{enumerate}
\hfill \mbox{\textit{Edexcel S4 Q1 [9]}}