Modeling the diameter distribution of trees in forest stands is a frequent application in ecology that supports key biologically and economically relevant management decisions. The choice of model used to represent the diameter distribution and how to estimate its parameters has received much attention in the forestry literature; however, accessible software that facilitates comprehensive comparison of the myriad modeling approaches is not available. To this end, we developed an R package called ForestFit that simplifies estimation of common probability distributions used to model tree diameter distributions, including the two- and three-parameter Weibull distributions, Johnson’s SB distribution, Birnbaum–Saunders distribution, and finite mixture distributions. Frequentist and Bayesian techniques are provided for individual tree diameter data, as well as grouped data. Additional functionality facilitates fitting curves to height-diameter data. The package also provides a set of functions for computing probability distributions and simulating random realizations from common finite mixture models.

对林分中树木的直径分布进行建模是生态学中的一种常见应用，可支持关键的生物学和经济相关管理决策。在林业文献中，用于表示直径分布的模型的选择以及如何估算其参数受到了广泛关注。但是，尚无法使用有助于全面比较各种建模方法的可访问软件。为此，我们开发了一个名为ForestFit的R包这简化了用于建模树木直径分布的常见概率分布的估计，包括两参数和三参数威布尔分布，约翰逊的SB分布，Birnbaum-Saunders分布和有限混合分布。为单个树径数据以及分组数据提供了频率和贝叶斯技术。附加功能有助于将曲线拟合到高度直径数据。该软件包还提供了一组函数，用于计算概率分布并模拟来自常见有限混合模型的随机实现。