Maths Summarising Data

Maths Summarising Data

1. Mode

   • Most common value
     • With continuous data in a frequency table we can pick a modal class

2. Median

   • Middle Value when all the data is arranged in ascending order
     • (n+1) /2

3. Mean

   • Average value of a set of numbers
     • Mean of a frequency table is x times by frequency for all values of x and added. Then divide by frequency
     • Sum of all values divided by number of values

4. Range

   • Largest value - smallest value

5. Interquartile Range

   • Upper quartile- lower quartile (Upper is 75%, Lower is 25%)
     • LQ = (n+1)/4
       • UQ = 3(n+1)/4

6. Standard Deviation

   • Square root of the variance

7. Variance

   • Spread of the data
     • Sum of all the squares of the data/ number of values