function [dSRTs_out, newSRT] = joergensen2011_pctodsrt(PC_input,SNRs,conditions)
%JOERGENSEN2011_PCTODSRT calculates the SRT and change in SRT
%
% Usage:
% [dSRTs_out, newSRT] = joergensen2011_pctodsrt(PC_input,SNRs,conditions)
%
% Input parameters:
% PC_input : Matrix with the mean percent correct for each processing
% condition and SNR. The first column of PC_input should always be the
% reference with no processing
% conditions : Vector with the processing conditions
% SNRs : Vector with the SNRs used.
%
% JOERGENSEN2011_PCTODSRT calculates the SRT and change in SRT from the simulated percent correct
%
% Url: http://amtoolbox.org/amt-1.3.0/doc/modelstages/joergensen2011_pctodsrt.php
% #StatusDoc: Submitted
% #StatusCode: Submitted
% #Verification: Untrusted
% #Requirements: M-Signal M-Stats
% #Author: Søren Jørgensen (2011)
% #Author: Peter L. Sondergaard (2014)
% This file is licensed unter the GNU General Public License (GPL) either
% version 3 of the license, or any later version as published by the Free Software
% Foundation. Details of the GPLv3 can be found in the AMT directory "licences" and
% at <https://www.gnu.org/licenses/gpl-3.0.html>.
% You can redistribute this file and/or modify it under the terms of the GPLv3.
% This file is distributed without any warranty; without even the implied warranty
% of merchantability or fitness for a particular purpose.
% ---------------- calculating dSRTs on mean psychofuncs.
for k = conditions
SNRsLong = 0;
yhat = 0;
% ----------- Connecting the points with streight lines-----------
for p = 1:length(SNRs)-1
tmp = polyfit(SNRs(p:p+1), PC_input(p:p+1,k)',1);
tmpSNR = SNRs(p):0.005:SNRs(p+1);
yhat_tmp = polyval(tmp,tmpSNR);
yhat = [yhat yhat_tmp];
SNRsLong = [SNRsLong tmpSNR];
end
yhat2(:,k) = yhat(2:end);
SNRsLong = SNRsLong(2:end);
SRT = 50;
hLine = linspace(SRT,SRT,length(yhat2(:,k)))';
C = abs(yhat2(:,k)-hLine); % Find minimum distance between horizontal line and estimated p_correct
SNRIndex = find(C==min(C));
if length(SNRIndex)>1
SNRIndex = SNRIndex(1);
end
newSRT(k) = SNRsLong(SNRIndex);
% ----------- calculating change in SRT ---------------------
dSRTs = abs(newSRT(1)-newSRT(k));
if newSRT(k) > newSRT(1)
dSRTs = dSRTs;
else
dSRTs = dSRTs*-1;
end
if min(C) > 1
dSRTs = -4;
end
if isempty(dSRTs)
dSRTs = -4;
end
dSRTs_out(k) = dSRTs;
end