representation. n. 1. the act or an instance of representing or the state of being represented. 2. anything that represents, such as a verbal or pictorial portrait. 3. anything that is represented, such as an image brought clearly to mind.
The standard deviation and range are both measures of the spread of a data set. Each number tells us in its own way how spaced out the data are, as they are both a measure of variation. The range relies on a very simple formula of subtracting the minimum data value from the maximum.
We will be looking at the range, quartiles, variance, absolute deviation and standard deviation. Range. The range is the difference between the highest and lowest scores in a data set and is the simplest measure of spread. So we calculate range as: Range = maximum value - minimum value. For example, let us consider the following data set: The maximum value is 85 and the minimum value is 23. This results in a range of 62, which is 85 minus 23. Whilst using the range as a measure of spread is limited, it does set the boundaries of the scores. This can be useful if you are measuring a variable that has either a critical low or high threshold (or both) that should not be crossed. The range will instantly inform you whether at least one value broke these critical thresholds.