20 marks Question 3 This question is based on your work on MU123 up to and including Unit 11. The Met Office keeps a number of weather stations collecting climate data across the UK. A few of them have been operational since the nineteenth century and, in particular, the one at Oxford is the oldest in service, collecting data since 1853. Carol is working on a small climate change project and has been looking at data from the Oxford weather station. The raw data in Table 1 show the average maximum daily temperature for the month of July for two sets of consecutive 30-year periods, the first from 1853-1882 and the second from 1992-2021. Table 1 Mean daily maximum temperature (C) for the month of July in Oxford (UK) 1853-1882 1992-2021 21.2 21.1 21.7 20.8 22.8 24.8 22.2 25.1 22.0 23.3 20.8 22.8 25.1 21.0 19.3 24.2 19.7 20.8 19.9 23.4 21.8 22.1 22.8 23.7 22.3 22.0 21.7 22.3 20.3 27.1 25.8 20.6 24.1 22.0 24.9 22.4 21.1 21.9 23.7 21.4 22.6 20.5 25.3 25.5 19.9 24.9 24.5 22.6 21.1 23.3 22.2 23.3 17.5 27.4 19.7 24.5 22.7 22.5 20.0 23.8 (a) Carol considers displaying the data as a pair of dotplots. Do you think this is a good idea for these particular datasets? Give a brief reason for your answer. page 5 of 12 (b) Carol decides to create a boxplot for each dataset as displayed in Figure 2. 16 18 20 [2] Figure 2 With reference to Subsection 1.2 of Unit 11, state three ways in which Carol could improve the clarity of her presentation of the boxplots. (c) Carol can't remember which boxplot belongs to which 30-year period. State one way in which she could check by looking at the raw data. (d) Carol realises that the top boxplot represents the data for 1853-1882 and the bottom boxplot represents the data for 1992-2021. She tries to interpret what the boxplots are telling her by making the statements below. For each one, state whether you agree or disagree with Carol's interpretation, and explain why you think she is correct or incorrect. (i) 'On average, the maximum temperature for July was higher in 1992-2021 compared to 1853-1882. (ii) 'Overall there was a larger variation in the July daily maximum temperatures in 1853-1882 compared to those in 1992-2021." (iii) 'During more than half of the years in 1853-1882 the maximum temperature for July was lower than the median." (e) Use the boxplot for 1992-2021 to say whether the data are symmetrical or skewed. If the data are skewed, then state whether they are skewed to the left or skewed to the right, explaining your reasoning briefly. [3] [1] 2 [2] (f) Carol creates (poorly presented) histograms for each of the two datasets, shown in Figures 3 and 4 below. 5 3 2 17 18 19 20 21 22 23 24 25 26 27 28 Figure 3 4 page 6 of 12 2. 11 17 18 19 20 21 22 23 24 25 26 Figure 4 (i) Which histogram belongs to the data for 1853-1882 - Figure 3 or Figure 4? Give a reason for your answer. (ii) Comment on one aspect-giving a specific example of the comparison of data from the two periods that can be seen more easily on the histograms than on the boxplots. [2] [2] (iii) Comment on one aspect-giving a specific example of the comparison of data from the two periods that can be seen more easily on the boxplots than on the histograms. [2]