Projects

The formulas and calculation results

Parameters

The overall coefficient of variation c

$c=\frac{\sqrt{\frac{1}{n-1}{\displaystyle \sum _{i=1}^n{\left(y_i-\overline{y}\right)}^2}}}{\overline{y}}$

n-the overall grid number;

y_i-forest area of the ith grid;

$\overline{y}$ -average number of total forest area;

S-the overall variance;

E-relative error;

Δ-absolute error;

A-the total area of the reservoir;

t-security probability 95%

Sample number n

$n=\frac{t^2{C}^2}{E^2}=\frac{t^2\frac{S^2}{{\overline{y}}^2}}{\frac{{\Delta }^2}{{\overline{y}}^2}}=\frac{t^2{S}^2}{{\Delta }^2}$

The sample spacing D

$D=\sqrt{\frac{A}{n}}$