What Does Sigma (σ) Mean in Different Fields?

Sigma (σ) is the most commonly used mathematical constant, and it is also called the standard deviation. Sigma is used as a measure of variability and can be used to describe the degree of dispersion or variation of a data set. The term also is used to describe the variability of a sample population.

The use of the Sigma sign in mathematics started with the Greek mathematician, Archimedes. He used the Greek letter Sigma as a symbol to represent the summation symbol in his calculations. Sigma (σ) is widely used in statistical theory and is very important to understand.

What is Sigma(σ)?

σ= standard deviation,

σ is the number that gives the average deviation of the given value from the mean.

This symbol is also used in statistics to represent the variance of the underlying distribution of the data. It can describe as Σd(x-μ).

Used for Symbols of Sigma in different fields

Sigma Symbols are used in many fields.

1. Astronomy

σ = the distance between a planet and the sun

2. Chemistry

σ = the standard deviation of atomic mass

3. Physics

σ = the standard deviation of energy of an electron

4. Biology

σ = the standard deviation of a gene

5. Statistics

σ = the standard deviation of a random variable

6. Mathematics

σ = the standard deviation of a function

7. Economics

σ = the standard deviation of the income of the individuals in a population

8. Engineering

σ = the standard deviation of a product

9. Geography

σ = the standard deviation of elevation

10. Geology

σ = the standard deviation of a geologic time scale

11. Ecology

σ = the standard deviation of a species

12. Geophysics

σ = the standard deviation of an earthquake

13. Meteorology

σ = the standard deviation of temperature

14. Psychology

σ = the standard deviation of a personality trait

15. Sociology

σ = the standard deviation of a social status

16. Law

σ = the standard deviation of a probability

17. Economics

σ = the standard deviation of a stock price

18. Finance

σ = the standard deviation of a financial return

19. Business

σ = the standard deviation of a firm’s profit margin

20. Education

σ = the standard deviation of student performance

21. History

σ = the standard deviation of a culture’s material production

22. Political science

σ = the standard deviation of a political party’s support

23. Physics

σ = the standard deviation of an electron’s velocity

24. Astronomy

σ = the distance from a planet to its host star

25. Chemistry

σ = the standard deviation of an element’s atomic mass

26. Geology

σ = the standard deviation of a geologic time scale

27. Biology

σ = the standard deviation of a gene

28. Physics

σ = the standard deviation of a particle’s energy

29. Economics

σ = the standard deviation of a stock price

What is Sigma in math?

In the world of mathematics, the symbol is used to signify different math processes involving deviations and summation. Discover the concept and definition of sigma and the purposes of the lower case and upper case sigma.

In mathematics, the lower case sigma stands for standard deviation. The upper case sigma is used for the summation notation. Each has its own unique formula, and yes, both the lower case and upper case look vastly different from each other. But they are both the Greek equivalent of it. If you note this the two formulas upper case and lower case that uses these two symbols both start with the letters.

• Σ= upper case sigma is used for the summation notation
• (σ)  the lower case sigma stands for standard deviation  

What is Upper Case Sigma?

The upper case sigma is used in the summation notation. This particular notation is also called sigma notation.

For example:

1+2+3+4+……+20= Σ²⁰_n=1(n)

1²+2²+3²+……+50²= Σ⁵⁰_n=1(n²)

What is lower case sigma stands for standard deviation? 

The lower case sigma stands for standard deviation .it is denoted by (σ).

 σ= standard deviation,

σ is the number that gives the average deviation of the given value from the mean