Coefficient of variation from duplicate measurements
The calculation of the Standard Deviation (SD) and Coefficient of Variation (CV) from duplicate measurements made on a number of different subjects or materials is used to determine the reproducibility of the measurements as an alternative to making a large number of observations on a single subject or material to calculate the SD and CV directly (Jones & Payne 1997).
In the dialog box you select the variables that contain the data for the two measurements. The order is not important.
With n being the number of data pairs and x1 and x2 duplicate measurements, the SD, Mean and CV are given by: