Question

In a study of male stalk-eyed flies, the distance between the eyes (which are out on stalks) was measured in mm. The 27 observations from randomly selected stalk-eyed flies are as follows: 1.89 1.93 2.02 2.03 2.10 2.11 2.16 2.16 1.95 1.96 2.04 2.05 2.12 2.13 2.19 2.20 1.99 2.00 2.01 2.08 2.08 2.08 2.13 2.14 2.15 2.23 2.23

4) [5 marks] Find the sample median of the between-eye distance.

5) [10 marks] Find the first and third quartiles of the distance between the eyes.

6) [5 marks] The upper fence is the value above which an observation is an outlier. Is there an outlier at the upper end?

7) [10 marks] Find the 95% confidence interval for μ, if the sample mean is 2.09 and the sample standard deviation is 0.092.

8) [6 marks] Identify what μ represents, and also identify the population and random variable associated with the confidence interval from (7).

Answer 1