Intern:Standard deviation/Standard error

This page is meant for PANGAEA editors.

This page was established from discussion in ticket PEB-12.

General: '''If an author provided data for standard deviation for a given parameter, the generic parameter "standard deviation" should not be used. Instead, a parameter with the parameter name, followed by standard deviation, e.g. Viability, standard deviation, has to be used!'''

Further methodological information, e.g. 1 or 2 sigma, are added using methods.

Example calculations and explanations:
https://www.mathsisfun.com/data/standard-deviation.html or https://www.mathsisfun.com/data/standard-deviation-formulas.html for calculations more in detail.

Standard deviation/Standardabweichung:
The Standard Deviation is a measure of how spread out numbers are in set of measurements; / Die Standardabweichung gibt an wie stark die Streuung der Werte um einen Mittelwert ist.


 * Symbol : σ (sigma)


 * Calculation : square root of variance


 * Unit : like the unit from the parameter the mean was calculated from
 * Usually standard deviation is given as 1 sigma, but 2 sigma is also reported

Variance/Varianz:

 * Symbol : σ2 (sigma square)
 * Calculation : Calculated from the difference of each measurement to the mean squared and then divided by the total number of measurements
 * Unit : square of the unit from the parameter the mean was calculated from

Standard error (SE) mostly Standard error of the mean (SEM):
Standard deviation of the means of several sets of measurements.


 * Symbo l: SE or SEM
 * Calculation : square root of variance or the means of set of measurements
 * Unit : ?

See: https://www.youtube.com/watch?v=A82brFpdr9g

Coefficient of variation/Variationskoeffizient (CV):
Sometimes called relative standard deviation (RSD)


 * Symbol : cv or VarK
 * Calculation: Standard deviation divided by mean
 * Unit : %

See: https://de.wikipedia.org/wiki/Variationskoeffizient, https://en.wikipedia.org/wiki/Coefficient_of_variation