13 Denzel wants to buy a car with a propulsion type other than petrol or diesel.
He takes a sample, from the Large Data Set, of the CO2 emissions, in \(\mathrm { g } / \mathrm { km }\), of cars with one particular propulsion type.
The sample is as follows
$$\begin{array} { l l l l l l l l }
82 & 13 & 96 & 49 & 96 & 92 & 70 & 81
\end{array}$$
13
- Using your knowledge of the Large Data Set, state which propulsion type this sample is for, giving a reason for your answer.
13 - Calculate the mean of the sample.
13 - Calculate the standard deviation of the sample.
13 - Denzel claims that the value 13 is an outlier.
13
- Any value more than 2 standard deviations from the mean can be regarded as an outlier.
Verify that Denzel's claim is correct.
13
- (ii) State what effect, if any, removing the value 13 from the sample would have on the standard deviation.