Stand Count Coefficient of Variation Calculation

Stand Count Coefficient of Variation Calculation

The Coefficient of Variation or CV is a statistical term that represents the level of dispersion of
samples around the mean in a unitless way (since both average and standard deviation have the
same units – their division is unitless, like a percentage). The higher the coefficient, the greater the
dispersion is.
In stand count scouting, CV usually refers to the seed spacing CV. It is calculat​​​ed by collecting seed
spacing samples across the field and calculating their statistical CV.
Currently in Taranis – our CV calculation is not done in the conventional manor.
We base our CV calculation on the average seed spaces measured in different locations in the field.
The conventional way:
Conventional CV = StDev(samples of seed space) / Average(samples of seed space)
Our current calculation:
Taranis CV = StDev(samples of average seed space) / Average(samples of average seed space)
Where the samples of average seed space are generated from each image collected throughout the
field.
Note: since the “Taranis CV” is based on the average seed spaces in the field it tends to be smaller
than the “Conventional CV”.
Since the Taranis CV is based on averaged samples measured across the field – it better captures the
disparity that originates from the variation through the field. We do however have the ability to
calculate the conventional CV per image and per field, and plan on adding that to our stand count
solution.
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