Dixon Statistical Test: Deriving Density Function

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The discussion focuses on the Dixon method for identifying outliers in normally distributed data, specifically detailing the critical value equation and the density function for extreme values. The critical value is defined as r01 = (xn - xn-1) / (xn - x1), while the density function involves a complex expression that includes factorials and integrals. Participants express difficulty in interpreting the LaTeX formatting, suggesting that using underscores for subscripts may improve clarity. There is a request for further explanation of the density function's derivation or references for better understanding. The conversation highlights the need for clear mathematical notation in statistical discussions.
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Recently, I was reading the Dixon (Annals Math. Stat. 22, (1951) 68-78) method for extreme (outliers) values. He considered that there are n ordered values (x1, x2, ...xn) of an analytical measurement. The values belong to a normal distribution. He defined two equations:
1. For Critical value

r01=\frac{x<sub>n</sub>-x<sub>n-1</sub>}{x<sub>n</sub>-x<sub>1</sub>}


2. The density function for x1, xn-1, xn is

\frac{n!}{(n-3)!}f(x1)dx1(\oint<sub>x<sub>1</sub></sub><sup>x<sub>n</sub>-1</sup>f(t)dt)n-3 f(xn-1)dxn-1f(xn) dxn

I will appreciate if someone explains the derivation of the density function or site some reference which explains it.

Thanks
 
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Mixing in the "SUB" tag in between LaTex expressions seems to screw up the LaTex display. I can't make out what the density function is supposed to be. Can you revise it using the underscore ? (such as using the notation x_{n-1} for x with a subscript of n-1).
 
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