| Exam Board | Edexcel |
|---|---|
| Module | S1 (Statistics 1) |
| Marks | 8 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Modelling and Hypothesis Testing |
| Type | Distribution selection for modeling |
| Difficulty | Easy -1.2 This is a straightforward S1 question testing basic understanding of statistical models and properties of the normal distribution. Part (a) requires simple recall of a definition, while part (b) asks students to apply basic knowledge about when normal distributions are appropriate (continuous vs discrete data, symmetry, range). No calculations or complex reasoning required—just recognition of standard criteria. |
| Spec | 2.04e Normal distribution: as model N(mu, sigma^2)2.04h Select appropriate distribution |
| Answer | Marks | Guidance |
|---|---|---|
| e.g. using a distribution or other simplified way of representing a real situation that allows predictions to be made about it | B2 | |
| (i) not suitable e.g. discrete etc. / +ve skew | B2 | |
| (ii) suitable e.g. likely to be similar time most days, sometimes fair but more, sometimes fair bit less | B2 | |
| (iii) not suitable e.g. very different values in winter / summer | B2 | (8) |
e.g. using a distribution or other simplified way of representing a real situation that allows predictions to be made about it | B2 |
(i) not suitable e.g. discrete etc. / +ve skew | B2 |
(ii) suitable e.g. likely to be similar time most days, sometimes fair but more, sometimes fair bit less | B2 |
(iii) not suitable e.g. very different values in winter / summer | B2 | (8)2. (a) Explain briefly what is meant by a statistical model.\\
(b) State, with a reason, whether or not the normal distribution might be suitable for modelling each of the following:
\begin{enumerate}[label=(\roman*)]
\item The number of children in a family;
\item The time taken for a particular employee to cycle to work each day using the same route;
\item The quarterly electricity bills for a particular house.
\end{enumerate}
\hfill \mbox{\textit{Edexcel S1 Q2 [8]}}