Chapter 10 Maths Analysing Data

Chapter 10 Maths Analysing Data

1. 10-01: Interpreting Graphs

   • Types of graphs
     • Picture graphs
     • Column graphs
       • Numerical values easier to see
         • Equal values easier to see
     • Divided bar graphs
       • Proportions easier to see
         • e.g. Blue is 1/4 of the population
     • Sector graphs
     • Line graphs

2. 10-02: Misleading Graphs

   • Factors:
     • No scale
     • Uneven scale
     • Incorrect use of picture
   • Not starting at 0, very exaggerated

3. 10-03: Dot Plots

   • Simple type of column graph
     • Uses dots to display frequency of each score
   • Shows:
     • any gaps in clusters
       • any clusters
         • any outliers
           • how the scores are spread out

4. 10-04: Stem and leaf plots

   • Like a sideways column graph
     • Lists the actual scores horizontally
   • Shows:
     • all scores, smallest t largest
       • most common scores
         • any clusters or outliers
           • how the scores are spread out

5. 10-05: The mean and mode

   • Mean
     • best known average
       • Found by adding the total of scores and dividing by the number of scores
   • Mode
     • Most frequent score
       • Can be numerous modes or no mode

6. 10-06: The median and range

   • Median
     • Middle score or average of the two in the middle
   • Range
     • Difference between the highest and lowest score

7. 10-07: Analysing Dot Plots and stem and leaf plots

   • Mean, median and mode can be found from data displayed on dot plots and stem and leaf plots

8. 10-08: Comparing Data Sets

   • Mean, median and mode are measures of location
   • Range is a measure of spread
   • Mean
     • Affected by outliers
     • Depends on scores in data set
   • Median
     • Not affected by outliers
       • Can be one of the scores
   • Mode
     • Can be more than one
       • Not affected by outliers
         • Needed when data has outliers
   • Range
     • Depends on highest and lowest scores