copy and paste this google map to your website or blog!
Press copy button and paste into your blog or website.
(Please switch to 'HTML' mode when posting into your blog. Examples: WordPress Example, Blogger Example)
Input Form:Deal with this potential dealer,buyer,seller,supplier,manufacturer,exporter,importer
(Any information to deal,buy, sell, quote for products or service)
病毒相关的报道里 mutation 和 variation 的区别是什么，能否通俗地讲解一下？ - 知乎 “Mutation and variation are two simultaneous events involved in the process of evolution The main difference between mutation and variation is that mutation is an alteration in the nucleotide sequence of a gene whereas variation is any difference between individuals of a particularspecies
什么是变异系数？ - 知乎 变异系数求解权重是一种客观法：数据的波动性可以衡量权重。如果变异系数越大，说明其携带的信息越大，因而权重也会越大，这是变异系数法求解权重的原理。 ※变异系数（Coefficient of variation）变异系数又称“标准差率”，是衡量资料中各观测值变异程度的另一个统计量。当进行两个或多个