 # How to Implement Normal Distribution in DAX - DAX in Power BI - Chapter 14

### We are going to explore 4 Normal Distribution statistical functions in DAX using practical examples.

Using DAX Statististical functions, we can very well determine the inferential statistics for different datasets in Power BI.

In this blog, you are going to explore how you can calculate Normal Distributions using DAX functions.

1. NORM.DIST,
2. NORM.INV,
3. NORM.S.DIST,
4. NORM.S.INV

## What is Distribution

Whenever we are discussing inferential statistics, the first is coming to the picture is Distribution.

In simple terms, a distribution is a function that represents the possible values occurrences of a variable.

Examples: Normal distribution, Student’s T distribution, Poisson distribution, Uniform distribution, Binomial distribution

## Normal Distribution

Normal Distribution is one of the most common distributions. It is also known as Bell Curve or Gaussian distribution.

Example: Stock Market data, most biological measures like height, blood pressure etc.

## NORM.DIST

The NORM.DIST returns the normal distribution for the specified mean and standard deviation.

The syntax for NORM.DIST is below

NORM.DIST(X, Mean, Standard_dev, Cumulative)

X= The value which will be used for distribution

Mean= Mean of the distribution

Standard_dev= Standard Deviation of distribution

Cummulative= Logical value (TRUE or FALSE). If cumulative is TRUE, NORM.DIST returns the cumulative distribution function; if FALSE, it returns the probability density function.

## NORM.INV

The NORM.INV function returns the inverse of the normal cumulative distribution for the specified mean and standard deviation.

The syntax is below

NORM.INV(Probability, Mean, Standard_dev)

Probability=A probability corresponding to the normal distribution.

Mean=The arithmetic mean of the distribution.

Standard_dev=The standard deviation of the distribution.

## Standard Normal Distribution

The Standard Normal Distribution is a particular case of the Normal Distribution. In this case, the mean is 0 and the standard deviation is 1.

## NORM.S.DIST

The NORM.S.DIST returns the standard normal distribution.

The syntax is below

NORM.S.DIST(Z, Cumulative)

Z= The value for which distribution will be calculated

Cumulative=Logical value (TRUE or FALSE). If cumulative is TRUE, NORM.DIST returns the cumulative distribution function; if FALSE, it returns the probability density function.

## NORM.S.INV

The NORM.S.INV returns the inverse of the standard normal cumulative distribution.

The syntax is below

NORM.S.INV(Probability)

Probability=A probability corresponding to the normal distribution.

## Hands-On: NORM.S.DIST and NORM.S.INV

Please find the code in the below location

DAX – Chapter 14

https://github.com/arpitag1/Power-BI

## Conclusion

The blog teaches us the 4 statistical functions (related to Normal Distribution) of DAX with practical examples.