1. Topic: Data Handling LO: To be able to understand and produce box plots. STARTER PREPARE FOR LEARNING AGREE LEARNING OBJECTIVES Calculate the median of these numbers: 5, 7, 3, 6, 10, 4, 8, 7, 7 3, 4, 5, 6, 7, 7, 7, 8, 10 11, 8, 9, 10, 3, 6, 8, 10 3, 6, 8, 8, 9, 10, 10, 11

3. PRESENT NEW INFO

4. Quartiles CONSTRUCT MEANING

5. Quartiles CONSTRUCT MEANING

6. Quartiles 20, 20, 21, 24, 27, 29, 33, 33, 36, 39, 50, 57, 60, 65, 65 CONSTRUCT MEANING

7. Quartiles 18, 23, 25, 27, 27, 37, 38, 45, 47, 49, 49, 50, 50, 58, 61, 66, 69 CONSTRUCT MEANING

8. Quartiles Golf Club AGolf Club B Lower Quartile2427 Median3347 Upper Quartile5754 Which golf club has more younger members? Which golf club has more older members? What can you say about the age profile of each golf club in general? DEMONSTATE UNDERSTANDING

9. Quartiles The Interquartile Range (IQR) is the upper quartile – the lower quartile It tells us how spread out the middle 50% of the data is Smaller IQR means more consistency and vice- versa CONSTRUCT MEANING

10. Quartiles Golf Club AGolf Club B Lower Quartile2427 Median3347 Upper Quartile5754 Golf Club AGolf Club B Lower Quartile2427 Median3347 Upper Quartile5754 Interquartile Range 3327 “Members of golf club B are more similar in age than in golf club A” CONSTRUCT MEANING

11. Box Plots A box plot is a way of illustrating key information about a set of data They are also very useful for comparing the distribution of two sets of data (e.g. boys vs girls) CONSTRUCT MEANING

12. Box Plots To draw a box plot, you need FIVE pieces of information: The minimum value The lower quartile The median The upper quartile The maximum value CONSTRUCT MEANING

13. Box Plots CONSTRUCT MEANING

14. Minimum Value: 3 Lower Quartile: 4 Median: 7 Upper Quartile: 9 Maximum Value: 10 Interquartile Range: 5 010 9 87 6 5 4 3 2 1 The Interquartile Range (IQR) is the UQ – LQ. It illustrates the spread of the middle 50% of the data. The larger the IQR, the more spread out, and less consistent the data. Maths Test Scores

15. The box plot below shows the data for 23 female students. 010 9 87 6 5 4 3 2 1 BOYS 010 9 87 6 5 4 3 2 1 Maths Test Scores GIRLS Girls median higher so on average, girls scored higher IQR lower so girls results were more consistent Girls minimum value was higher so boys scored the lowest

16. Golf Club AGolf Club B Minimum Value1819 Lower Quartile2427 Median3347 Upper Quartile5754 Maximum Value6367 Box Plots Draw box plots to represent the age of members of the two golf clubs DEMONSTATE UNDERSTANDING

17. Box Plots Below are the midday temperatures for Ringwood over the past 11 days (in o C). 20, 22, 16, 17, 16, 18, 20, 18, 16, 21, 18 Below are the midday temperatures for Glasgow over the past 11 days (in o C). 17, 20, 20, 17, 16, 14, 13, 19, 21, 17, 18 Draw box plots for the data and write some comments on what they tell you about the temperatures in Ringwood and Glasgow over the past 11 days. REVIEW