Plavcan J M
Department of Biological Sciences, University of Cincinnati, Ohio 45221.
Am J Phys Anthropol. 1994 Aug;94(4):465-76. doi: 10.1002/ajpa.1330940403.
Estimating sexual dimorphism in skeletal and dental features of fossil species is difficult when the sex of individuals cannot be reliably determined. Several different methods of estimating dimorphism in this situation have been suggested: extrapolation from coefficients of variation, division of a sample about the mean or median into two subsamples which are then treated as males and females, and finite mixture analysis (specifically for estimating the maximum dimorphism that could be present in a unimodal distribution). The accuracy of none of these methods has been thoroughly investigated and compared in a controlled manner. Such analysis is necessary because the accuracy of all methods is potentially affected by fluctuations in either sample size, sex ratio, or the magnitude of intrasexual variability. Computer modeling experiments show that the mean method is the least sensitive to fluctuations in these parameters and generally provides the best estimates of dimorphism. However, no method can accurately estimate low to moderate levels of dimorphism, particularly if intrasexual variability is high and sex ratios are skewed.
当无法可靠地确定化石物种个体的性别时，估算其骨骼和牙齿特征中的两性差异是困难的。针对这种情况，已经提出了几种不同的估算两性差异的方法：根据变异系数进行外推、将样本按均值或中位数划分为两个子样本，然后将其分别视为雄性和雌性，以及有限混合分析（专门用于估算单峰分布中可能存在的最大两性差异）。这些方法的准确性均未在可控条件下得到彻底研究和比较。进行此类分析很有必要，因为所有方法的准确性都可能受到样本大小、性别比例或性别内变异性大小波动的影响。计算机模拟实验表明，均值法对这些参数的波动最不敏感，通常能提供对两性差异的最佳估算。然而，没有哪种方法能够准确估算低到中等程度的两性差异，尤其是当性别内变异性较高且性别比例失衡时。
