Conclusion

Measures of central tendency, or averages, summarise a data set by a single most-representative value.

• The arithmetic mean is the most commonly used. It is simple to compute and uses every observation, but it is unduly affected by extreme values, which can make it unrepresentative.
• The median is a better summary when the data contains extreme items, since it depends on position rather than on the size of every value. It also handles open-ended distributions easily and can be found graphically.
• The mode is generally used to describe qualitative data and, like the median, can be located graphically and in open-ended distributions. …