/usr/share/psychtoolbox-3/PsychProbability/ is in psychtoolbox-3-common 3.0.11.20140816.dfsg1-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/psychtoolbox-3/PsychProbability/BalanceFactors.m
/usr/share/psychtoolbox-3/PsychProbability/BalanceTrials.m
/usr/share/psychtoolbox-3/PsychProbability/BuildMarkovK.m
/usr/share/psychtoolbox-3/PsychProbability/ChiSqrCumulative.m
/usr/share/psychtoolbox-3/PsychProbability/ChiSquarePDF.m
/usr/share/psychtoolbox-3/PsychProbability/ChooseKFromN.m
/usr/share/psychtoolbox-3/PsychProbability/ClockRandSeed.m
/usr/share/psychtoolbox-3/PsychProbability/CoinFlip.m
/usr/share/psychtoolbox-3/PsychProbability/CoinFlipPDF.m
/usr/share/psychtoolbox-3/PsychProbability/ColMean.m
/usr/share/psychtoolbox-3/PsychProbability/ColStd.m
/usr/share/psychtoolbox-3/PsychProbability/CombVec.m
/usr/share/psychtoolbox-3/PsychProbability/Contents.m
/usr/share/psychtoolbox-3/PsychProbability/CovToCorr.m
/usr/share/psychtoolbox-3/PsychProbability/FindNeighborCorr.m
/usr/share/psychtoolbox-3/PsychProbability/MultiNormalDraw.m
/usr/share/psychtoolbox-3/PsychProbability/MultiNormalPDF.m
/usr/share/psychtoolbox-3/PsychProbability/NRandPerm.m
/usr/share/psychtoolbox-3/PsychProbability/NormalCumulative.m
/usr/share/psychtoolbox-3/PsychProbability/NormalDraw.m
/usr/share/psychtoolbox-3/PsychProbability/NormalPDF.m
/usr/share/psychtoolbox-3/PsychProbability/NormalProb.m
/usr/share/psychtoolbox-3/PsychProbability/RandDim.m
/usr/share/psychtoolbox-3/PsychProbability/RandLim.m
/usr/share/psychtoolbox-3/PsychProbability/RandSample.m
/usr/share/psychtoolbox-3/PsychProbability/RandSel.m
/usr/share/psychtoolbox-3/PsychProbability/Randi.m
/usr/share/psychtoolbox-3/PsychProbability/Ranint.m
/usr/share/psychtoolbox-3/PsychProbability/Sample.m
/usr/share/psychtoolbox-3/PsychProbability/Shuffle.m
/usr/share/psychtoolbox-3/PsychProbability/URandSel.m
/usr/share/psychtoolbox-3/PsychProbability/UniqueAndN.m
/usr/share/psychtoolbox-3/PsychProbability/UniqueNoSorting.m