A quantity expressing by how much the members of a group differ from the mean value for the group.
- ‘All costs are reported as mean values with standard deviations.’
- ‘Mean values and standard deviations were calculated for all variables.’
- ‘If no standard deviations were reported then we used the average standard deviation for all the remaining studies.’
- ‘Each value is the mean standard deviation of at least four independent measurements.’
- ‘Average values and standard deviations were then calculated for each of the compounds in the experiment.’
We take a look at several popular, though confusing, punctuation marks.