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.
Note that there really isn't a standard meaning for the size of an error bar. Common choices are: 1 (the range would include about 68% of normal data), 2 which is basically the same as 95% limits, and 0.674Ã which would include 50% of normal data. The above may be a population standard deviation or a standard deviation of the mean.