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# wraylplot

## PURPOSE

Plots data on a Rayleigh distribution paper

## SYNOPSIS

bhat = wraylplot(x)

## DESCRIPTION

WRAYLPLOT Plots data on a Rayleigh distribution paper

CALL:  bhat = wraylplot(X)

bhat = Parameter of the distribution estimated from the
plot by least squares method.
X = data

Example:
R=wraylrnd(1,1,100);
wraylplot(R);

## CROSS-REFERENCE INFORMATION

This function calls:
 empdistr Computes and plots the empirical CDF hold Hold current graph. plot Linear plot. title Graph title. xlabel X-axis label. ylabel Y-axis label.
This function is called by:
 dist2dfit Parameter estimates for DIST2D data.

## SOURCE CODE

001 function bhat = wraylplot(x)
002 %WRAYLPLOT Plots data on a Rayleigh distribution paper
003 %
004 % CALL:  bhat = wraylplot(X)
005 %
006 %   bhat = Parameter of the distribution estimated from the
007 %          plot by least squares method.
008 %   X = data
009 %
010 % Example:
011 %   R=wraylrnd(1,1,100);
012 %   wraylplot(R);
013 %
015
016 % Reference: Cohen & Whittle, (1988) "Parameter Estimation in Reliability
017 % and Life Span Models", p. 181 ff, Marcel Dekker.
018
019 %tested on: matlab 5.1
020 % rewritten ms 15.06.2000
021
022 F=empdistr(x,[],0);
023 plot(F(:,1),sqrt(-log(1-F(:,2))),'b.','markersize',12)
024 U=[ones(size(F(:,1))) F(:,1)];
025 c=U\sqrt(-log(1-F(:,2)));
026 b=1/c(2)/2^(1/2);
027 hold on
028 plot(F(:,1),U*c,'r--')
029 hold off
030 title('Rayleigh Probability Plot')
031 xlabel('X')
032 ylabel('(-log(1-F))^{1/2}')
033 if nargout > 0,
034   bhat=b;
035 end
036

Mathematical Statistics
Centre for Mathematical Sciences
Lund University with Lund Institute of Technology

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