AS/A2 Statistical Tests

• For Chi-Square:

  • If the calculated value is LARGER than the critical value, reject the null hypothesis
  • If the calculated value is SMALLER than the critical value, accept the null hypothesis
• Chi-Square:

  • It does not indicated what the association between the data sets actually is
  • It will show that there is something going on geographically concerning where something (i.e. local food retailers) are located
• Standard Deviation:

  • Measures the difference between each data value and the mean and calculates the average variation
  • It is liable to being influenced by extreme outlier measurements, but the impact can be reduced by having larger sample sizes
• A normal distribution is that in which data is evenly spread out either side of the mean

  A) Mean

  
• An uneven (or skewed) distribution is that in which the spread of the data favours one side of the mean over the other

  A) mean