# What is the product of two Gaussian distributions?

## What is the product of two Gaussian distributions?

The product of two Gaussian PDFs is proportional to a Gaussian PDF with a mean that is half the coefficient of x in Eq. 5 and a standard deviation that is the square root of half of the denominator i.e. as, due to the presence of the scaling factor, it will not have the correct normalisation.

## Is the product of two Gaussians Gaussian?

Since the product of two Gaussians is a Gaussian, the posterior probability is Gaussian. It is not normalized, but that is where P[˜X] (which we “threw out” earlier) comes in. It must be exactly the right value to normalize this distribution, which we can now read off from the variance of the Gaussian posterior.

## Can you multiply two normal distributions?

The product of two normal PDFs is proportional to a normal PDF. Note that the product of two normal random variables is not normal, but the product of their PDFs is proportional to the PDF of another normal. …

## Is the product of two normal variables normal?

The distribution of the product of normal variables is not, in general, a normally distributed variable. In 2003 Ware and Lad  published an article where restart the problem of the probability of the product of two Normally distributed variables.

## What is the product of two random variables?

the product of two random variables is a random variable; addition and multiplication of random variables are both commutative; and. there is a notion of conjugation of random variables, satisfying (XY)* = Y*X* and X** = X for all random variables X,Y and coinciding with complex conjugation if X is a constant.

## How do you find the standard deviation of a product?

How to Measure the Standard Deviation for a Sample (s)

1. Calculate the mean of the data set (x-bar)
2. Subtract the mean from each value in the data set.
3. Square the differences found in step 2.
4. Add up the squared differences found in step 3.
5. Divide the total from step 4 by (n – 1) for sample data.

## What is var aX bY?

Var(aX + bY) = a2 Var(X) + b2 Var(Y).

## Can you multiply distributions?

Distribution involves multiplying each individual term in a grouped series of terms by a term outside of the grouping. A term is made up of variable(s) and/or number(s) joined by multiplication and/or division. Terms are separated from one another by addition and/or subtraction.

## What is expectation of product?

Expectation of product of random variables When two random variables are statistically independent, the expectation of their product is the product of their expectations. This can be proved from the law of total expectation: In the inner expression, Y is a constant.

## How do you add two independent variables?

Sum: For any two independent random variables X and Y, if S = X + Y, the variance of S is SD^2= (X+Y)^2 . To find the standard deviation, take the square root of the variance formula: SD = sqrt(SDX^2 + SDY^2).

## Is the product of two Gaussian PDFs a PDF?

As you noticed, the product of two gaussian PDFs is not a PDF. However, as any positive integrable function, it is proportional to another PDF, which happens to be itself gaussian. The rest is calculus. ( − 1 2 σ 2 ( x − μ) 2).

## Is the product of two random variables a Gaussian?

The Product of Two Gaussian Random Variables is not Gaussian distributed: Is the product of two Gaussian random variables also a Gaussian? But the product of two Gaussian PDFs is a Gaussian PDF: What is going on here? What am I doing when I take the product of two pdfs vs. when I take the product of two variables from the pdfs?

## How to multiply two Gaussian PDFs with intuition 2?

Intuition 2 (Multiplying Gaussian PDFs): Now you’re multiplying not the numbers but the functions together. The multiplying is just a bunch of algebra and the resulting function also fits the form factor of a Gaussian.

## Which is the posterior probability of two Gaussian PDFs?

The measurement model tells us that P [ X ~ ∣ X] is Gaussian, in particular P [ X ~ ∣ X] = N [ Σ ϵ, X]. Since the product of two Gaussians is a Gaussian, the posterior probability is Gaussian.