Distribution of Range of Samples taken from N(0,1)

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SUMMARY

The discussion centers on the "Studentized Range" distribution, specifically its implementation in R through the functions ptukey(x,n,dof) and qtukey(x,n,dof). The user inquires about a named distribution for the range of samples taken from a standard normal distribution N(0,1), noting that such a distribution is not commonly recognized or tabulated. They mention that while it can be approximated using large degrees of freedom in the Studentized Range, no distinct named distribution exists for N(0,1). The user has implemented a method to compute this distribution in GNU Octave, achieving good agreement with the asymptotic behavior of the existing functions.

PREREQUISITES
  • Understanding of the Studentized Range distribution and its applications.
  • Familiarity with R programming, specifically the ptukey() and qtukey() functions.
  • Knowledge of statistical distributions, particularly the normal distribution N(0,1).
  • Basic proficiency in GNU Octave for implementing statistical methods.
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  • Research the properties of the Studentized Range distribution in detail.
  • Explore the implementation of statistical functions in R and GNU Octave.
  • Investigate the derivation and applications of the distribution of the sample range for continuous random variables.
  • Learn about asymptotic behavior in statistical distributions and its implications.
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Statisticians, data analysts, and researchers interested in statistical distributions, particularly those working with sample ranges and normal distributions. Additionally, R and Octave users looking to implement or understand the Studentized Range distribution will find this discussion beneficial.

uart
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TL;DR
Is there a name for the probability distribution of the range of a sample (size n) taken from a standard normal population?
I recently came across a distribution called the "Studentized Range" (for example, implemented as ptukey(x,n,dof) and qtukey(x,n,dof) in the R software package). Essentially it's the distribution of the range (max sample value - min sample value), for a sample (size n) taken from a student_t distribution (degrees of freedom dof).

Was just curious if there is a named distribution for the same thing except with the sample being taken from N(0,1) instead of student_t. Basically I was wondering if it's a distribution that's already implemented in various stats packages of if it just remains unnamed and unloved?

I know it can be approximated by just using a large dof in existing "Studentized Range" implementations like ptukey(), but wondering if it already exists as a named and tabulated distribution in it's own right.
 
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Just updating this thread. As far as I call tell this distribution is not commonly named or tabulated. It can however be computed from the following equation, which is a general expression for the distribution of the range (W) of a sample of random variables with distribution,density F(x),f(x).

$$F_W(W) = n \int_{-\infty}^\infty f(u) [F(u+W) - F(u)]^{n-1} du$$

I have now implemented this (crudely) in gnu Octave and it gives very good agreement with the asymptotic behavior (for large dof) of the ptukey/qtukey functions mentioned above. Can post the .m files if anyone is interested, but be warned the implementation is extremely crude and inefficient, as it was just to test that the method worked.

Reference: https://demonstrations.wolfram.com/DistributionOfTheSampleRangeOfContinuousRandomVariables/
 
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