Questions tagged [uniform]

The uniform distribution describes a random variable that is equally likely to take any value in its sample space.

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Mean and variance of a normally distributed random number created from the average of a set of uniformly distributed random numbers

An old-fashioned way of generating normally distributed random numbers entailed setting each normally distributed random number equal to the average of a set of uniformly distributed random numbers, ...
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Distribution of a ratio of uniforms: What is wrong?

Suppose that $X$ and $Y$ are two i.i.d. uniform random variables on the interval $[0,1]$ Let $Z=X/Y$, I am finding the cdf of $Z$, i.e. $ \Pr(Z\leq z) $. Now, I came up with two ways of doing this. ...
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Generating random samples from a custom distribution

I am trying to generate random samples from a custom pdf using R. My pdf is: $$f_{X}(x) = \frac{3}{2} (1-x^2), 0 \le x \le 1$$ I generated uniform samples and then tried to transform it to my custom ...
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Why are p-values uniformly distributed under the null hypothesis?

Recently, I have found in a paper by Klammer, et al. a statement that p-values should be uniformly distributed. I believe the authors, but cannot understand why it is so. Klammer, A. A., Park, C. Y.,...
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Uniform random variable distribution

This is a homework problem out of the book. It says If $U$ is a uniform random variable on [0,1], what is the distribution of the random variable $X = [nU]$, where [$t$] denotes the greatest ...
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How to perform goodness of fit test and how to assign probability with uniform distribution? [duplicate]

I have to demonstrate that a generator of VoIP calls generates calls uniformly distributed between callers. In particular the distribution is the uniform (min, max) one where the volume per caller ...
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1answer
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Uniform Distribution Test

I've got a data-set which I assume is uniformly distributed. Say I've got N=20000 samples and a suspected p=0.25. This means ...
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3answers
25k views

Are there default functions for discrete uniform distributions in R?

Most standard distributions in R have a family of commands - pdf/pmf, cdf/cmf, quantile, random deviates (for example- dnorm, pnorm, qnorm, rnorm). I know it's easy enough to make use of some ...
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Difference between Excel's RAND(), RAND()*RAND(), etc

I plotted below the standarized results of: RAND() RAND() * RAND() ... RAND() * RAND() * RAND() * RAND() * RAND() * RAND() It seems that the results are getting to zero, is that because you're ...
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How can I test the fairness of a d20?

How can I test the fairness of a twenty sided die (d20)? Obviously I would be comparing the distribution of values against a uniform distribution. I vaguely remember using a Chi-square test in ...
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What is the expected MINIMUM value drawn from a uniform distribution between 0 and 1 after n trials?

Assume you draw a uniformly distributed random number between 0 and 1 n times. How would one go about calculating the expected minimum number drawn after n trials? In addition, how would one go ...
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Testing implementation of Anderson-Darling test for uniform RV

I am trying to write unit tests for a whole mess of statistics code. Some of the unit tests take the form: generate a sample following a null hypothesis, use code to get a p-value under that null, ...
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What would the calculated value of the standard deviation of a uniform distribution be?

A colleague wants to compare models that use either a Gaussian distribution or a uniform distribution and for other reasons needs the standard devation of these two distributions to be equal. In R I ...