I'm confronted by a table of values:
17.1 (16.6) 18.0 (9.5) 38.1 (22.5) 30.6 (16.7)
In the left-hand column we have some mean values. I’m told that the values in parenthesis are 'one standard deviation of the mean' Which I understand to be a range, within which 68% of values would fall.
What I want to know is THE standard deviation associated with the numbers on the left. Am I missing something? Is something perhaps wrong with the information supplied to me in the table? If not, is there a way to move from 'one standard deviation' to 'the standard deviation'. The sample size in every case is 5.
In response to the excellent answers and insights already posted, I have added more detail in the comments. Here is the table I am looking at:
Here is a reference to the information:p184 for the data table in question (Table5), Catena, 2008, 'Surface soil hydraulic properties in four soil series under different land uses and their temporal changes' X. Zhou a,⁎, H.S. Lin a, E.A. White p:184