sigma background

sigma

/ˈsɪɡmə/

Illustration sigma - Image 1

noun

西格玛，Σ。

The eighteenth letter of the Classical and Modern Greek alphabets, the twentieth letter of Old and Ancient.

Examples :

"In Greek class, we learned that sigma is the eighteenth letter of the alphabet. "

在希腊语课上，我们学到西格玛（sigma）是希腊字母表的第十八个字母。

language writing sign

Illustration sigma - Image 1

noun

求和符号, Σ (西格玛)。

The symbol Σ, used to indicate summation of a set or series.

Examples :

"The math textbook explained how to use the sigma notation (Σ) to easily represent the sum of many numbers in a sequence. "

这本数学课本讲解了如何使用求和符号 (Σ) ，也叫做西格玛符号，来简便地表示一个数列中许多数字的总和。

math number sign statistics

Illustration sigma - Image 1

noun

西格玛，标准差。

The symbol σ, used to indicate one standard deviation from the mean, particularly in a normal distribution.

Examples :

"The teacher explained that a score one sigma above the mean in the math test meant the student performed better than most of the class. "

老师解释说，数学考试中，如果一个分数比平均分高出一个西格玛（标准差），就意味着这个学生的表现优于班里的大部分同学。

math statistics