function scorediagplot(Xdist,Odist,k,cutoffx,cutoffo,attrib,labsd,labod)
%SCOREDIAGPLOT plots the score outlier map. The score distances (SD) and
% orthogonal distances (OD) calculated in a PCA analysis are plotted
% on the x and y-axis, respectively.
% The cutoff values marked by a red line indicate which observations are
% outlying with respect to the majority of the data. The terminology used is
% as indicated in the tabular:
% small SD | large SD
% ----------------------------------------------------------
% small OD | regular point | good PCA-leverage point
% large OD | orthogonal outlier | bad PCA-leverage point
%
% For more details see:
% Hubert, M., Verboven, S. (2003),
% "A robust PCR method for high-dimensional regressors",
% Journal of Chemometrics, 17, 438-452.
%
% Required input arguments:
% Xdist : Score distances out of a PCA analysis
% Odist : Orthogonal distances out of a PCA analysis
% k : Number of principal components used in a PCA/PCR analysis
% cutoffx : Cutoff value for the score distances
% (=97.5% quantile of a chisquare with k degrees of freedom)
% attrib : string identifying the used method = RPCR, ROBPCA, CPCR,
% CPCA, MCDREG...
%
% Optional inputs
% labsd : number of displayed points with largest score distance (default = 3)
% labod : number of displayed points with largest orthogonal distance (default=3)
%
% I/O: scorediagplot(out.sd,out.od,out.k,out.cutoff.sd,out.cutoff.od,'RPCR',3,5)
%
% This function is part of LIBRA: the Matlab Library for Robust Analysis,
% available at:
% http://wis.kuleuven.be/stat/robust.html
%
% Written by S. Verboven
% Last update: 20/06/2003
%Checking input
if nargin==7
labod=3;
end
if nargin==6
labsd=3;
labod=3;
end
if nargin<6
error('no class identifier is given.')
end
%INITIALISATION%
%in case k=rank(T)=r then OD = zero
NihilO=(Odist <= 1.e-06);
Odist(NihilO)=0;
NihilX=(Xdist <= 1.e-06);
Xdist(NihilX)=0;
if ~any(Odist) %OD=0: x=index and y=Xdist
x=(1:length(Xdist))';
y=Xdist;
difflabel=1; %change name of the axis-labels
if ~any(Xdist)
axes
box on
text(0.05,0.5,'The score outliermap is not drawn when all OD and SD are zero.','color','r')
return
end
elseif ~any(Xdist) % SD=0: x=index and y=Odist
x=(1:length(Xdist))';
y=Odist;
difflabel=2; %change name of the axis-labels
else
x=Xdist;
y=Odist;
difflabel=0;
end
quantx=cutoffx;
set(gcf,'Name', 'Score outlier map', 'NumberTitle', 'off');
hold on
xmin=0;
xmax=max([x; cutoffx]);
ymin=0;
ymax=max([y; cutoffo]);
xmarg=0.06*(xmax-xmin);
ymarg=0.06*(ymax-ymin);
xmin=xmin-xmarg;
xmax=xmax+xmarg;
ymin=ymin-ymarg;
ymax=ymax+ymarg;
n=length(x);
plot(x,y,'o');
if difflabel==1 %in case OD = 0
ymax=max(ymax,cutoffx+ymarg);
xlabel('Index')
ylabel(['Score distance (',num2str(k),' LV)'])
line('Xdata',[xmin xmax] ,'Ydata',[cutoffx cutoffx],'Linestyle','-','Color','r');
xlim([xmin,xmax]);
ylim([ymin,ymax]);
box on
plotnumbers(x',y,0,labsd,2);
title(attrib)
hold off
elseif difflabel==2 %case SD = 0
xmax=max(xmax,cutoffo+xmarg);
xlabel('Index')
ylabel(['Orthogonal distance (',num2str(k),' LV)'])
line('Xdata',[xmin xmax] ,'Ydata',[cutoffo cutoffo],'Linestyle','-','Color','r');
xlim([xmin,xmax]);
ylim([ymin,ymax]);
box on
plotnumbers(x',y,0,labod,2);
title(attrib)
hold off
else
xlabel(['Score distance (',num2str(k),' LV)']);
ylabel('Orthogonal distance');
line([cutoffx cutoffx],[ymin ymax] ,'Linestyle','-','Color','r');
line('Xdata',[xmin xmax] ,'Ydata',[cutoffo cutoffo], 'Linestyle','-','Color','r');
xlim([xmin,xmax]);
ylim([ymin,ymax]);
box on
plotnumbers(x',y,labsd,labod,2);
title(attrib)
hold off
end