Probability density function

So the normalized value is preserved in the convolution.In summary, it is generally true that the convolution of two normalized probability density functions is also normalized. This can be shown by using the formula for convolution and substituting u for y-x in the integral, resulting in the product of two integrals, each of which equals 1, thus preserving the normalized value.
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aaaa202
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If g and f are two normalized probability density functions is it then true in general that the convolution of f and g is normalized too?
 
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  • #2
Yes. The convolution is the density function for the sum of the random variables which have g and f as density functions.
 
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how do you show that normalization is preserved..
 
  • #4
aaaa202 said:
how do you show that normalization is preserved..

Let f(x) = g(x)*h(x) (where * means convolution). ∫f(x)dx = ∫g(x)dx∫h(y-x)dy. Let u = y-x for the h integral (remember these integrals are over the entire real line) and you have the product of 2 integrals, each of which is 1.
 
  • #5


Yes, it is true in general that the convolution of two normalized probability density functions is also normalized. This is because the convolution of two functions represents the probability distribution of the sum of two random variables, and when both functions are normalized, the resulting distribution will also be normalized. This can be mathematically proven using the properties of convolution and the definition of a normalized function. Therefore, the convolution of two normalized probability density functions will always result in a normalized probability density function.
 

FAQ: Probability density function

1. What is a probability density function (PDF)?

A probability density function (PDF) is a mathematical function that describes the relative likelihood of a continuous random variable taking on a particular value. It is used to represent the probability distribution of a continuous random variable.

2. How is a probability density function different from a probability mass function?

A probability density function is used for continuous random variables, while a probability mass function is used for discrete random variables. This means that a probability density function assigns probabilities to intervals of values, while a probability mass function assigns probabilities to individual values.

3. What is the area under a probability density function?

The area under a probability density function represents the probability of the random variable falling within a certain range of values. This area is always equal to 1, as the total probability of all possible outcomes must equal 1.

4. How is a probability density function used in statistics?

In statistics, a probability density function is used to calculate the probability of a continuous random variable falling within a certain range of values. It is also used to estimate the likelihood of observing a particular value or set of values in a sample from a larger population.

5. How is a probability density function related to the cumulative distribution function?

The cumulative distribution function (CDF) is the integral of the probability density function (PDF) and represents the probability that a random variable is less than or equal to a certain value. In other words, the CDF is the accumulated probability up to a certain point, while the PDF is the rate at which the probabilities accumulate.

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