In this study, seven popular equations, including 3-parameter Weibull, 2-parameter Weibull, Gompertz, Logistic, Mitscherlich, Korf and R distribution, were used to model stand diameter distributions for exploring the relationship between the equations' inflection point attributes and model accuracy. A database comprised of 146 diameter frequency distributions of Chinese fir (Cunninghamia lanceo...

Variables assessed included (1) inflection point, (2) compliance index (CI), and (3) modified compliance index (MCI). These variables are illustrated in Figure 2. Inflection point was defined as the point of intersection of the linear portions. CI was defined as the difference in displacements at 67 and 89 N of anterior force [2]. MCI was defined as the compliance of post-inflection stiffness o...