Code for identifying patient zero in epidemic models

Contains code for exact source identification of epidemic models. predictaverage.m compares different numerical solvers attempting to return the exact time inversion of Markovian SIS. ReversetimeNIMFA.m visualizes our backwards NIMFA method. reversetimefindsourceexact.m implements our algorithm that tries to determine the length of the epidemic and then use that to exactly invert to the initial condition (up to numerical errors). Accuratetimebeta.m and

Accuratetimepernumberofdigits.m show the accuracy of our Backwards NIMFA method for different values of the infection rate and different numbers of accurate digits. SISEuler.m and SISEulerbackintime.m are functions that solve NIMFA numerically, forward and backwards in time respectively.