| Exam Board | OCR MEI |
|---|---|
| Module | AS Paper 2 (AS Paper 2) |
| Year | 2024 |
| Session | June |
| Marks | 3 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Bivariate data |
| Type | Identify outliers or unusual points |
| Difficulty | Easy -1.8 This is a straightforward interpretation question requiring only basic scatter diagram reading skills. Students simply need to describe visible patterns (positive/negative correlation, strength) and comment on representativeness—no calculations, statistical tests, or deep conceptual understanding required. This is well below average difficulty for A-level, being purely descriptive data interpretation. |
| Spec | 2.01d Select/critique sampling: in context2.02c Scatter diagrams and regression lines2.02d Informal interpretation of correlation |
| Answer | Marks | Guidance |
|---|---|---|
| Answer | Mark | Guidance |
| Positive association or positive correlation | B1 | May be a contextual interpretation e.g. 'as the mobile phone subscribers per 100 population increases, real GDP per capita also increases.' Ignore references to 'strong/weak' etc. 'Linear' not required. Contradictory statements lose the mark. |
| Answer | Marks | Guidance |
|---|---|---|
| Answer | Mark | Guidance |
| Negative association or negative correlation | B1 | Accept 'as the mobile phone subscribers per 100 population increases, real GDP per capita decreases' o.e. Ignore references to 'strong/weak' etc. Contradictory statements lose the mark. |
| Answer | Marks | Guidance |
|---|---|---|
| Answer | Mark | Guidance |
| Neither/None of them – samples are same size and different samples can lead to different conclusions. Or 'Neither as the patterns of the data contrast/are different'. | B1 | Allow e.g. neither since combining results suggests no correlation. SC: IF they interpret (b) as 'little/no correlation' then they can score for a correct FT reason e.g. superimposing (a) onto (b) implies no real relationship. SC: From pre-release material/large data set accept 'the first scatter diagram is more representative of the true relationship as the PMCC is positive for this data when all countries in Africa are considered'. Any reference to sample size being too small is B0. 'Neither as the patterns of the data contrast/are different' is B1 |
## Question 5:
### Part (a):
| Answer | Mark | Guidance |
|--------|------|----------|
| Positive association or positive correlation | B1 | May be a contextual interpretation e.g. 'as the mobile phone subscribers per 100 population increases, real GDP per capita also increases.' Ignore references to 'strong/weak' etc. 'Linear' not required. Contradictory statements lose the mark. |
### Part (b):
| Answer | Mark | Guidance |
|--------|------|----------|
| Negative association or negative correlation | B1 | Accept 'as the mobile phone subscribers per 100 population increases, real GDP per capita decreases' o.e. Ignore references to 'strong/weak' etc. Contradictory statements lose the mark. |
### Part (c):
| Answer | Mark | Guidance |
|--------|------|----------|
| Neither/None of them – samples are same size and different samples can lead to different conclusions. Or 'Neither as the patterns of the data contrast/are different'. | B1 | Allow e.g. neither since combining results suggests no correlation. **SC:** IF they interpret (b) as 'little/no correlation' then they can score for a correct FT reason e.g. superimposing (a) onto (b) implies no real relationship. **SC:** From pre-release material/large data set accept 'the first scatter diagram is more representative of the true relationship as the PMCC is positive for this data when all countries in Africa are considered'. Any reference to sample size being too small is B0. 'Neither as the patterns of the data contrast/are different' is B1 |
---5 The pre-release material contains information for countries in the world concerning real GDP per capita in US\$ and mobile phone subscribers per 100 population. In an investigation into the relationship between these two variables, a student takes a sample of 20 countries in Africa. The student draws a scatter diagram for the data, which is shown in Fig. 5.1.
\section*{Fig. 5.1}
\section*{Africa 1st sample}
\includegraphics[max width=\textwidth, alt={}, center]{ce94c1ea-ffe5-42d0-8f8a-43c47105d6bf-4_433_1043_842_244}
\begin{enumerate}[label=(\alph*)]
\item What does Fig. 5.1 suggest about the relationship between real GDP per capita and the number of mobile phone subscribers per 100 population?
Another student collects a different sample of 20 countries from Africa, and draws a scatter diagram for the data, which is shown in Fig. 5.2.
\section*{Fig. 5.2}
\section*{Africa 2nd sample}
\begin{center}
\includegraphics[max width=\textwidth, alt={}]{ce94c1ea-ffe5-42d0-8f8a-43c47105d6bf-4_273_1084_1818_244}
\end{center}
Mobile phone subscribers per 100 population
\item What does Fig. 5.2 suggest about the relationship between real GDP per capita and the number of mobile phone subscribers per 100 population?
\item Explain whether either of the two scatter diagrams is likely to be representative of the true relationship between real GDP per capita and the number of mobile phone subscribers per 100 population, for countries in Africa.
\end{enumerate}
\hfill \mbox{\textit{OCR MEI AS Paper 2 2024 Q5 [3]}}