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.
Standard Deviation. The standard deviation is a measure of the variability of the distribution of a random variable. To estimate the standard deviation. calculate the weighted sum of the squares of the differences of the observations in a simple random sample from the sample mean.