fp_pr_pac.m

function [pm] = fp_pr_pac(cc,iroi_amplt,iroi_phase)
% Copyright (c) 2023 Franziska Pellegrini and Stefan Haufe

%number of interactions 
nints = numel(iroi_phase);

%number of regions 
nroi = size(cc,1);

%true labels 
label=diag(ones(nroi,1));
for iint = 1:numel(iroi_phase)
    label(iroi_amplt(iint),iroi_phase(iint)) = 2;
end
lab = label(:);
cc = cc(:);

%remove diagonal entries 
cc(lab==1)=[];
lab(lab==1)=[]; 

%index of true label 
tr = find(lab==2); 

%estimated scores 
[~, idx] = sort(cc,'descend');

%rank of estimated scores 
for it = 1:numel(tr)
    r1(it) = find(idx==tr(it));
end

%% percentage rank

pm = mean(1 - (r1 ./ numel(lab)));

%normalize with perfect skill and noskill PR 
for it = 1:nints
    perfectPm(it) = 1 - (it / numel(lab));
    noSkillPm(it) = 1 - (numel(lab)-it+1)/numel(lab);
end
perfectPm = mean(perfectPm);
noSkillPm = mean(noSkillPm);

pm = (pm-noSkillPm)/(perfectPm-noSkillPm);