We present a detailed comparison of three different simulations of the epochof reionization (EoR). The radiative transfer simulation (${\rm C}^2$-RAY)among them is our benchmark. Radiative transfer codes can produce realisticresults, but are computationally expensive. We compare it with twosemi-numerical techniques: one using the same halos as ${\rm C}^2$-RAY as itssources (Sem-Num), and one using a conditional Press-Schechter scheme (CPS+GS).These are vastly more computationally efficient than ${\rm C}^2$-RAY, but usemore simplistic physical assumptions. We evaluate these simulations in terms oftheir ability to reproduce the history and morphology of reionization. We findthat both Sem-Num and CPS+GS can produce an ionization history and morphologythat is very close to ${\rm C}^2$-RAY, with Sem-Num performing slightly bettercompared to CPS+GS. We also study different redshift space observables of the 21-cm signal fromEoR: the variance, power spectrum and its various angular multipole moments. Wefind that both semi-numerical models perform reasonably well in predictingthese observables at length scales relevant for present and future experiments.However, Sem-Num performs slightly better than CPS+GS in producing thereionization history, which is necessary for interpreting the futureobservations.
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