| Exam Board | AQA |
|---|---|
| Module | AS Paper 2 (AS Paper 2) |
| Year | 2020 |
| Session | June |
| Marks | 4 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Permutations & Arrangements |
| Type | Linear programming and optimization |
| Difficulty | Easy -2.5 This is a statistics question requiring only basic recall of sampling method definitions and their advantages/disadvantages. No calculations, mathematical reasoning, or problem-solving required—just straightforward textbook knowledge about sampling bias, stratification, and systematic sampling. Well below average difficulty for A-level. |
| Spec | 2.01c Sampling techniques: simple random, opportunity, etc2.01d Select/critique sampling: in context |
| Answer | Marks |
|---|---|
| 14(a) | Explains clearly that the sample is |
| Answer | Marks | Guidance |
|---|---|---|
| (OE) | 2.4 | E1 |
| Subtotal | 1 |
| Answer | Marks |
|---|---|
| 14(b) | Expresses the idea that method B |
| Answer | Marks | Guidance |
|---|---|---|
| Do not accept references to time | 2.4 | E1 |
| Answer | Marks |
|---|---|
| Subtotal | 1 |
| Answer | Marks | Guidance |
|---|---|---|
| 14(c)(i) | States Systematic (sampling) | |
| (CAO) | 1.2 | B1 |
| Subtotal | 1 |
| Answer | Marks |
|---|---|
| 14(c)(ii) | Explains clearly, in context, the |
| Answer | Marks | Guidance |
|---|---|---|
| equally likely to be selected. | 2.4 | E1 |
| Answer | Marks | Guidance |
|---|---|---|
| Subtotal | 1 | |
| Question Total | 4 | |
| Q | Marking Instructions | AO |
Question 14:
--- 14(a) ---
14(a) | Explains clearly that the sample is
likely to be biased (OE)
Do not accept “the sample is not
random” alone.
Accept “this method does not
guarantee to get an employee or
opinions from each or other
store(s)” (OE)
Accept “people from same large
store may have similar opinions”
(OE) | 2.4 | E1 | Likely to be a biased sample
Subtotal | 1
--- 14(b) ---
14(b) | Expresses the idea that method B
ensures that there is representation
from every store
(OE)
Method B gives every employee
the opportunity of being chosen
(OE)
Do not accept references to time | 2.4 | E1 | It guarantees to get responses
from each store
Subtotal | 1
--- 14(c)(i) ---
14(c)(i) | States Systematic (sampling)
(CAO) | 1.2 | B1 | Systematic sampling
Subtotal | 1
--- 14(c)(ii) ---
14(c)(ii) | Explains clearly, in context, the
idea that all samples of size 100
are not possible to be chosen using
this method so the method is not
random.
Do not accept each person is not
equally likely to be selected. | 2.4 | E1 | Not all subsets of employees of
size 100 are possible, so each
sample of size 100 is not equally
likely to be selected, so not
random.
Subtotal | 1
Question Total | 4
Q | Marking Instructions | AO | Marks | Typical SolutionA retail company has 5200 employees in 100 stores throughout the United Kingdom.
The company recently introduced a new reward scheme for its staff.
The management team wanted to sample the staff to find out their opinions of the new scheme.
Three possible sampling methods were suggested:
Method A \quad Choose 100 people who work at the largest store
Method B \quad Choose one person at random from each of the 100 stores
Method C \quad List all employees in alphabetical order and assign each a number from 1 to 5200
Choose a random number between 1 and 52
Choose this person and every 52nd person on the list thereafter.
\begin{enumerate}[label=(\alph*)]
\item Give one disadvantage of using Method A compared with using Method B.
[1 mark]
\item Give one advantage of using Method B compared with using Method C.
[1 mark]
\item \begin{enumerate}[label=(\roman*)]
\item Identify the method of sampling used in Method C.
[1 mark]
\item Give a reason why Method C does not provide a random sample.
[1 mark]
\end{enumerate}
\end{enumerate}
\hfill \mbox{\textit{AQA AS Paper 2 2020 Q14 [4]}}