Biomass Modelling of Androstachys johnsonii Prain: A Comparison of Three Methods to Enforce Additivity

Table 4

Standard error of the expected and predicted values for different methods.

Statistic	Absolute form	Relative form
Standard error of the expected value for CON
Standard error of the predicted value for CON
Standard error of the expected value for SUR
Standard error of the predicted value for SUR
Standard error of the expected value for NSUR
Standard error of the predicted value for NSUR

Sources: Parresol [13], Lambert et al. [23], Parresol and Thomas [24], Snedecor and Cochran [25], and Yanai et al. [26].
= sum of squares of the independent variable; = standard deviation of the residuals; = particular value of for which the expected value is estimated, ; = estimated variance for the ith system equation on the observation ; = a row vector for the ith equation from the partial derivatives matrix , it is transposed;   = estimated covariance matrix of the parameter estimates; = a column vector for the ith equation from the partial derivatives matrix ; = SUR system variance; = NSUR system variance; = the element of the covariance matrix of the residuals (error covariance matrix); it is the covariance error of the ith system equation; and = estimated weight.