AQA Further Paper 3 Statistics 2023 June — Question 4 5 marks

Exam BoardAQA
ModuleFurther Paper 3 Statistics (Further Paper 3 Statistics)
Year2023
SessionJune
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicT-tests (unknown variance)
TypeSingle sample t-test
DifficultyStandard +0.3 This is a straightforward application of a one-sample t-test with all values provided. Students need to calculate the test statistic using the standard formula, compare to critical values from t-tables, and state a conclusion. While it's a Further Maths topic, it requires only direct substitution into a formula and table lookup with no problem-solving or conceptual challenges, making it slightly easier than average.
Spec5.05c Hypothesis test: normal distribution for population mean

4 The random variable \(X\) has a normal distribution with unknown mean \(\mu\) and unknown variance \(\sigma ^ { 2 }\) A random sample of 8 observations of \(X\) has mean \(\bar { x } = 101.5\) and gives the unbiased estimate of the variance as \(s ^ { 2 } = 4.8\) The random sample is used to conduct a hypothesis test at the \(10 \%\) level of significance with the hypotheses $$\begin{aligned} & \mathrm { H } _ { 0 } : \mu = 100 \\ & \mathrm { H } _ { 1 } : \mu \neq 100 \end{aligned}$$ Carry out the hypothesis test.

Question 4:
AnswerMarks Guidance
Answer/WorkingMark Guidance
\(t_7\) at \(95\% = 1.895\)B1 Correct critical value; PI by correct p-value
\(t = \frac{101.5 - 100}{\sqrt{\frac{4.8}{8}}} = 1.94\)M1 t-test statistic with sample mean and standard deviation; condone \(z=\)
\(t = 1.94\) (AWRT 1.94); or p-value AWRT 0.0468A1 Correct t-test statistic; condone \(z=\)
\(1.94 > 1.895\)R1 Evaluate t model by correctly comparing test statistic with critical value, or p-value with 0.05
Reject \(H_0\)E1 Infers \(H_0\) rejected from correct comparison using correct test statistic and critical value or p-value and 0.05
Question total: 5 marks
## Question 4:

| Answer/Working | Mark | Guidance |
|---|---|---|
| $t_7$ at $95\% = 1.895$ | B1 | Correct critical value; PI by correct p-value |
| $t = \frac{101.5 - 100}{\sqrt{\frac{4.8}{8}}} = 1.94$ | M1 | t-test statistic with sample mean and standard deviation; condone $z=$ |
| $t = 1.94$ (AWRT 1.94); or p-value AWRT 0.0468 | A1 | Correct t-test statistic; condone $z=$ |
| $1.94 > 1.895$ | R1 | Evaluate t model by correctly comparing test statistic with critical value, or p-value with 0.05 |
| Reject $H_0$ | E1 | Infers $H_0$ rejected from correct comparison using correct test statistic and critical value or p-value and 0.05 |

**Question total: 5 marks**

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4 The random variable $X$ has a normal distribution with unknown mean $\mu$ and unknown variance $\sigma ^ { 2 }$

A random sample of 8 observations of $X$ has mean $\bar { x } = 101.5$ and gives the unbiased estimate of the variance as $s ^ { 2 } = 4.8$

The random sample is used to conduct a hypothesis test at the $10 \%$ level of significance with the hypotheses

$$\begin{aligned}
& \mathrm { H } _ { 0 } : \mu = 100 \\
& \mathrm { H } _ { 1 } : \mu \neq 100
\end{aligned}$$

Carry out the hypothesis test.\\

\hfill \mbox{\textit{AQA Further Paper 3 Statistics 2023 Q4 [5]}}