There are several different methods and summary statistics that can be used to summarise a series of numbers to give a rough indication of a typical value. They are summary statistic as they represents a summary of a set of data. The mode is one such summary statistic, and it the most commonly occurring value or category. Most of the data within our Joint Strategic Needs Assessment website are continuous numerical data where there is unlikely to be a ‘most common’ value so the mode has not generally been used here. The median (middle value) and the average or arithmetic mean (or just ‘mean’) are two other summary statistics which are used to summarise a set of data and give a rough indication of a ‘typical’ value, and the average or arithmetic mean is much more commonly used.
The mode is the most frequently occurring value in a set of values. For instance, if there were four people aged 18, 18, 20 and 40 then the mode would be 18 as there are two people aged 18 years but only one person each aged 20 years and 40 years. In some case, the mode does not represent the ‘typical’ value very well, but it is the best measure when the data is categorical (discrete categories) for instance, where the were 12 houses in a street with three of them with red doors, two with blue doors and seven with white doors, then the modal category would be white.
The most frequently used measure of a ‘typical’ value is the average or mean, but house prices and income are often summarised using medians as there are often a small number of individual records with very high values which makes the median a more appropriate summary measure. The mode is generally not used, but useful for non-numerical data.