Even though most AIC values of model 3 are lower than model 2
(Table 2), the values are relatively the same. Therefore for fitting
the models, the emphasis will be given more on the coefficient of
the regression, average deviation, the range of CI, and paired t-test.
Of the proposed models, model 1 gives a better prediction than
model 2. This can be observed from the inclusion of CBH into the
model. It increases r
2 slightly and the average deviation decreases
slightly, but the slope less significant and the standard error of a
coefficient also increases. Based on the lower and upper limit CI of
the mixed species, model 1 is closer to the range of the mean of the
observed values (Table 4). In contrast, the upper and lower limit of
CI of model 2 does not reach the range of CI of the observed values.
For the mixed species, model 1 is significantly different from model
2 (Table 5). Model 1 is therefore the preferred model for estimating
the TAGB of Dipterocarp forests