产品相似性指数.doc

精品文档 2016 全新精品资料-全新公文范文-全程指导写作–独家原创 1 /22 产品相似性指数下文是关于产品相似性指数相关内容, 希望对你有一定的帮助: 产品相似性指数(一) 群 落相似性指数计算数据表群落相似性指数计算数据表产品相似性指数(二) 生 物间相似性的多样性指标数学建模网络挑战赛承诺书我们仔细阅读了第四届“互动出版杯”数学中国数学建模网络挑战赛的竞赛规则。我们完全明白,在竞赛开始后参赛队员不能以任何方式(包括电话、电子邮件、网上咨询等) 与队外的任何人( 包括指导教师) 研究、讨论与赛题有关的问题。我们知道, 抄袭别人的成果是违反竞赛规则的, 如果引用别人的成果或其他公开的资料(包括网上查到的资料) ,必须按照规定的参考文献的表述方式在正文引用处和参考文献精品文档 2016 全新精品资料-全新公文范文-全程指导写作–独家原创 2 /22 中明确列出。我们郑重承诺,严格遵守竞赛规则,以保证竞赛的公正、公平性。如有违反竞赛规则的行为,我们将受到严肃处理。我 们允许数学中国网站(/retype/zoom/ba6bd4100b4e767f5acfce28?pn=3&x=0&y=0 &raww=232&rawh=72&o=jpg_6_0_______&type=pic&aimh=72 &md5sum=99fbb5885c8c430fe4233d62b&sign=a044e c1321&zoom=&png=3231-5408&jpg=0-3064" target="_blank"> Abstract Presently, most of biodiversity indices rely on either richness or evenness. Although these indices more or less reflect the total number of species and the homogeneity of distribution of each species, but they all ignore one thing, the degree of difference or similarity among species. This considerably drove these indices apart from the definition of biodiversity. In this article, we aim at this defect, and give two 精品文档 2016 全新精品资料-全新公文范文-全程指导写作–独家原创 3 /22 models, tree model and statistic entropy model. In tree model, we refer to the classical classification theory ( classify species by several levels including phylum, class, order, family, genus, species ), and we assign a weight to each node in the taxonomic tree. We calculate the difference degree between two species according to their corresponding path (and the weight of each node in this path) in the taxonomic tree. We define the difference between one specie and a set of species to be the average difference degree between this specie and each specie within the set. Finally, we define the biodiversity degree of this set of species to be the sum of the average difference (with respect to this set) of each specie in the set. We argued that tree model index has relative plexity ( not as it seems to be ), high flexibility ( generalizable ) etc. For examp