Function name

Equation

Reference

Chi square statistic ( ${\chi }^2$ )

${\chi }^2={\displaystyle \sum }_{i=1}^n\frac{{\left(x_{iexp}-x_{ipred}\right)}^2}{x_{ipred}}$

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Accuracy (A_f)

$A_f=10\left({\displaystyle \sum }_{i=1}^N\left|\log \left(\frac{x_{ipred}}{x_{iexp}}\right)\right|/N\right)$

[52]

Bias (B_f)

$B_f=10\left({\displaystyle \sum }_{i=1}^N\log \left(\frac{x_{ipred}}{x_{iexp}}\right)/N\right)$

[52]

% Relative Variance, RV%

$\text{RV}\%=100\times {\left({\displaystyle \sum }_{i=1}^n{\left(\frac{x_{iexp}-x_{ipred}}{x_{iexp}}\right)}^2\frac{1}{n-p}\right)}^{0.5}$

[37]

Absolute fraction of variance

$\text{AFV}=1-\frac{{{\displaystyle \sum }}_{i=1}^n{\left(x_{ipred}-x_{iexp}\right)}^2}{{{\displaystyle \sum }}_{i=1}^n{\left(x_{iexp}\right)}^2}$

[23]

Relevance Factor (RF)

$\text{RF}\left(In{p}_k,P_T\right)=\frac{{{\displaystyle \sum }}_{i=1}^n\left(In{p}_{k,i}-\overline{In{p}_k}\right)\left(P_{Ti}-\overline{P_T}\right)}{\sqrt{{\left(In{p}_{k,i}-\overline{In{p}_k}\right)}^2{{\displaystyle \sum }}_{i=1}^n{\left(P_{Ti}-\overline{P_T}\right)}^2}}$

[69]