📐 变异系数计算器Coefficient of Variation Calculator
输入一组数据，计算变异系数 CV = 标准差 ÷ 平均值，同时给出平均值和标准差；可选样本或总体标准差，用来比较量纲或平均水平不同的数据的离散程度。Enter a data set to get the coefficient of variation, CV = standard deviation ÷ mean, along with the mean and standard deviation. Choose sample or population SD; CV lets you compare spread between data with different units or levels.
使用说明与常见问题How-to & FAQ
「变异系数计算器」是什么？What is the Coefficient of Variation Calculator tool?
输入一组数据，计算变异系数 CV = 标准差 ÷ 平均值，同时给出平均值和标准差；可选样本或总体标准差，用来比较量纲或平均水平不同的数据的离散程度。Enter a data set to get the coefficient of variation, CV = standard deviation ÷ mean, along with the mean and standard deviation. Choose sample or population SD; CV lets you compare spread between data with different units or levels.
如何使用「变异系数计算器」？How do I use the Coefficient of Variation Calculator tool?
在「变异系数计算器」中，填写「标准差类型」等参数，结果会随输入实时计算并显示在下方。In the Coefficient of Variation Calculator: Fill in "Standard deviation type"; results are recalculated instantly as you type.
变异系数怎么算？How is CV calculated?
CV = 标准差 ÷ |平均值|，常写成百分比。样本标准差除以 n − 1，总体标准差除以 n。CV = standard deviation ÷ |mean|, usually shown as a percentage. The sample SD divides by n − 1, the population SD by n.
什么时候用 CV？When is CV useful?
比较平均水平或单位不同的数据的相对离散程度，例如比较身高（cm）和体重（kg）的波动。数据须为比例尺度（有真正的零点且都为正）；摄氏温度这类数据的 CV 没有意义。To compare relative spread between data with different levels or units, such as height (cm) and weight (kg). The data should be on a ratio scale (a true zero, all positive); CV of Celsius temperatures, for example, is meaningless.
计算精度如何？How precise are the results?
「变异系数计算器」使用 JavaScript 双精度浮点数（约 15–16 位有效数字）；极大或极小的数值可能存在精度误差。The Coefficient of Variation Calculator uses double-precision floating point (about 15–16 significant digits); very large or very small values may lose precision.
「变异系数计算器」免费吗？需要注册吗？Is the Coefficient of Variation Calculator free? Do I need an account?
「变异系数计算器」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Coefficient of Variation Calculator is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.