Derivation of Box-Muller Transform: Exponential Distrib.

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In summary, the Box-Muller Transform is a method for generating normally distributed random numbers through a series of mathematical operations. It is important in statistics and data analysis because many real-world phenomena follow a normal distribution. The relationship between the Box-Muller Transform and the exponential distribution allows for the generation of exponential random numbers. In practice, the Box-Muller Transform involves transforming two independent, uniform random numbers into two independent, normally distributed random numbers. However, there are limitations and assumptions associated with this method, such as only being able to generate numbers with a mean of 0 and standard deviation of 1, and the assumption of truly independent and uniformly distributed input. Other methods may be more suitable in certain situations.
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rabbed
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In derivation of the box-muller transform, the joint distribution p(x,y) = e^(-r^2/2)/(2*pi) is interpreted as the product of a uniform distribution 1/(2*pi) and an exponential distribution e^(-x/2), but isn't an exponential distribution defined as k*e^(-k*x)? What happened to the coefficient?
 
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You are missing a constant.
 
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derivation: Start with [itex]\frac{1}{2\pi}e^{\frac{-x^2-y^2}{2}}dxdy[/itex]. Change to polar coordinates. [itex]\frac{1}{2\pi}e^{\frac{-r^2}{2}}
rdrd\theta[/itex]. For you picture [itex]s=r^2,\ so\ ds=2rdr,\ or\ rdr=\frac{ds}{2}[/itex]. There's the coefficient.
 
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Thanks mathman :)
 

FAQ: Derivation of Box-Muller Transform: Exponential Distrib.

What is the Box-Muller Transform and how is it derived?

The Box-Muller Transform is a method for generating pairs of independent, normally distributed random numbers. It is derived using the inverse transform method, which involves transforming a uniform distribution into a desired distribution through a series of mathematical operations.

Why is the Box-Muller Transform important in statistics and data analysis?

The Box-Muller Transform is important because it allows us to generate normally distributed random numbers, which are commonly used in statistical analysis and modeling. Many real-world phenomena follow a normal distribution, so being able to generate random numbers with this distribution is crucial in understanding and predicting these phenomena.

What is the relationship between the Box-Muller Transform and the exponential distribution?

The Box-Muller Transform can be used to generate normally distributed random numbers from a uniform distribution. The exponential distribution is a special case of the normal distribution, where the mean and variance are equal. Therefore, the Box-Muller Transform can be used to generate random numbers that follow an exponential distribution.

How does the Box-Muller Transform work in practice?

In practice, the Box-Muller Transform involves generating two independent random numbers from a uniform distribution between 0 and 1, then using a series of mathematical operations to transform these numbers into two independent, normally distributed random numbers.

Are there any limitations or assumptions associated with the Box-Muller Transform?

One limitation of the Box-Muller Transform is that it can only generate normally distributed random numbers with a mean of 0 and a standard deviation of 1. Additionally, it assumes that the input random numbers are truly independent and uniformly distributed, which may not always be the case in real-world data. Other methods, such as the Ziggurat algorithm, may be more appropriate in certain situations.

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