欲比較兩群落的相似性，相似性指標是常被利用的工具，文獻中已經有許多學者，提出包含物種豐富性訊息的相似性指標。本文中，亦提出一系列的相似性指標，其以參數定義不同的相似性指標，其中，此系列指標包含了Morisita-Horn index、 abundance Jaccard index、和abundance Sorensen index三個已被學者定義的指標。進一步針對提出的新指標，討論其特性及估計量性質。除了證得其估計量具有漸近一致性外，也利用模擬比較文中提出之估計量的優劣。並以實際例子，了解如何應用相似性指標於熱帶雨林的演變。

For comparing two communities, different similarity indices based on species relative abundance data have been proposed in the past. A new class of similarity indices, in which various indices can be defined according to different parameter values, is described in this article. Some of the similarity indices proposed in the past can be included in this class as well, such as Morisita-Horn index, abundance Jaccard index, and abundance Sorensen index. The properties of the proposed indices are described and compared to the conventional indices.
Asymptotically consistent estimators of the indices are proposed. The effects of different sample sizes and species diversities on different indices in the proposed index family are illustrated by simulation studies. Also the proposed indices are compared to the conventional ones on the data of successional vegetation in six tropical forests.

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