1. STATISTICS The study concerned with the - collection - organisation - display - analysis - interpretation of data Data is the information collected. Data can be collected- by survey - by observation - from existing sources

2. Organising and Displaying Data 1. Frequency Table (Tally Table) A table set up with three headings - What you are counting eg. Favourite colour, age - Tally - Frequency (Total)

3. Example: A class was surveyed to find out the number of pets per household and the data recorded: 0, 3, 1, 2, 0, 1, 0, 1, 2, 4, 0, 6, 1, 1, 0, 2, 2, 0, 1, 3, 0, 1, 2, 1, 1, 2. Draw a frequency table to organise this information. Number of PetsTallyFrequency 0 1 2 3 4 5 6 Exercise: Getting To Know You p 33 – 35 Q1, 4, 5

4. 2. Dot Frequency Diagram Dot Frequency Diagrams are a way of displaying data where dots corresponding to the data are placed above a number line. Example: The ages of audience members at a rap concert were recorded. 12, 14, 16, 14, 15, 16, 16, 16, 11, 14, 15, 12, 12, 11, 13, 15, 16, 14, 13, 13, 13, 14, 15. Display this data as a dot frequency diagram Exercise: Getting to Know You p 34 – Birth Months Dots must be spread evenly

5. 3. Grouped Frequency Tables If a set of data is very large or widely spread, the data can be organised into groups or class intervals. It is important to use intervals that are of equal size. Example: The number of goals scored by a basketball team in a season of 20 matches are: 25, 38, 16, 65, 42, 45, 18, 23, 12, 14, 21, 42, 40, 36, 9, 30, 56, 32, 37, 58. Construct a frequency table to display this information.

6. Goals ScoredTallyFrequency 1 - 10 11 - 20 21 - 30 31 - 40 41 - 50 51 - 60 61 - 70 Exercise: Use the heights from Getting to Know You to construct a frequency table.

7. 4. Stem and Leaf Diagram A stem and leaf diagram is made up of two parts - the stem - the leaf Eg stem leaf 2 8 represents 28 Example: the ages at which several women married are shown: 32, 33, 26, 32, 16, 22, 45, 18, 26, 39, 33, 48, 27, 31, 36, 28, 25, 23, 42, 26. Construct a stem and leaf diagram

8. Ages Women Marry Stem Leaf Exercise: Getting to Know You p 34 Q 2 – Heights Exercise A p 35 - 39