Measures of central tendency
Also called: Statistical averages · Topic: Geographical Data: Sources, Compilation and Processing · NCERT: Class 12, Ch 2 "Data Processing"; Class 12, Ch 4 "Spatial Information Technology"
Meaning
Measures of central tendency, also called statistical averages, give one value that stands for the centre of a data set. This is the point around which most values gather. The three main ones are the mean (sum of values ÷ number of values), the median (the middle value of an ordered series) and the mode (the value that occurs most often). Each suits a different kind of data, so the right choice matters.
Example
For seven Malwa plateau districts in Madhya Pradesh, the mean normal rainfall is 926.29 mm. This one figure sums up rainfall in the region. For incomes, where a few very high values pull up the mean, the median is the better choice.
Don't confuse with
- Measures of dispersion: show how spread out the values are (range, standard deviation), not where their centre lies.