Mean, median, mode

Average is a rather imprecise term. It has mathematical connotations, but it is used in everyday speech to mean or imply a variety of different things. ‘Average’ is generally taken to refer to ‘the mean’, but it is not always clear from the context. This can create problems in translation, particularly technical translations in which precision is paramount.

Mean, median and mode, by contrast, are precisely defined mathematical concepts. In the case of a perfectly symmetrical bell curve of data then the three numbers will coincide, but if you have skewed data then, of course, they won’t.

The mean is the mathematical average of a set of numbers. The average is calculated by adding up two or more scores and dividing the total by the number of values.
Consider the following number set: 2, 4, 6, 9, 12. The mean is calculated in the following manner: 2 + 4 + 6 + 9 + 12 = 33 / 5 = 6.6. So the mean of the number set is 6.6.

The median is the score located at the center of a number distribution. Consider this set of numbers: 2, 3, 6, 8, 10. The median of this number distribution is 6. For distributions with an even number of values, take the average of the two extreme values to find the median.

The mode is the most frequently occurring value in a number distribution. Consider the following number distribution of 2, 3, 6, 3, 7, 5, 1, 2, 3, 9. The mode of these numbers would be 3, since three is the most frequently occurring number.