MATLAB: What is the meaning of the upper and lower bounds on mean and sigma using RANDTOOL in the Statistics Toolbox

randrandtoolStatistics and Machine Learning Toolboxtool

I am using RANDTOOL to look at a normal distribution of a dataset generated at different means and standard deviations. I am confused as to what the upper and lower bounds of mean and sigma on the RANDTOOL GUI refer to.

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The upper and lower bounds on mean and sigma refer to the upper and lower limits on the scroll bar that is used to move the mean and sigma values up and down. These parameters do not effect the values of the mean and sigma of the distribution in any way.

Note that when you change the upper or lower bound of mean or sigma, the distribution gets resampled and updated.

Related Solutions

MATLAB: Hi – please what is the difference between normrnd and randn

1. what is the difference between normrnd and randn?

doc normrnd
 r = normrnd(mu,sigma) generates a random number from the normal distribution with mean
 parameter mu and standard deviation parameter sigma.
doc randn
 X = randn returns a random scalar drawn from the standard normal distribution.

"Standard normal distribution" is a mean of 0.0 and a standard deviation of 1.0 . This means:

normrnd(mu, sigma) = randn * sigma + mu

2. How to use normrnd to generate random numbers from normal distribution with specific mean and variance ?

Simply by calling: normrnd(mu, sigma)

Remember that normrnd uses the standard deviation, which is the square root of the variance.

Do you know the doc and help commands? You find the documentation of the current Matlab version online also: https://www.mathworks.com/help/index.html

MATLAB: Question in the Statistics

x and y are independent, so E(z) = E(x)*E(y).

You do not know what E(x) is because all that you are given is the range of x, and nothing about the distribution of x. Likewise with E(y).

If The distribution is Uniform Random, then E() of a uniform random variable is mean() of the range. mean() of 0 to 1 is 1/2.

1/2 * 1/2 gives 1/4

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MATLAB: Hi – please what is the difference between normrnd and randn

MATLAB: Question in the Statistics

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