STUDY UNIT 3
Central tendency
Measures of central tendency are the measures of location.
- They typical values that summarises the distribution.
Three types of measures of central tendency/measures of location
i. Arithmetic mean
ii. Median
iii. Mode
Arithmetic mean
- The sum of all the values in the data set divided by the number of observations (n).
∑𝑥
- It is symbolised by the population mean (𝜇) and it is given by
𝑛
Steps of how to calculate the mean
• Add all the given observations and find the total (∑ 𝑥)
• Count the number of observations (n)
• Divide the total numbers of observations (sum) by the number of observation
(n)
The median
- Is the centre of the distribution when data is arranged in ascending or descending
order.
- It divides the data set in two parts.
The mode
- Is the most frequent value in the data set.
How to calculate mean and standard deviation using a calculator