conditional_mle         Compute MLE based on the full information R1,
                        R2, R3 and R4.
covid19_austria         COVID-19 Data from Statistics Austria
get_prob                Compute sucess probabilities (tau_j's)
marginal_mle            Compute (marginalized) MLE based on the partial
                        information R1 and R3.
moment_estimator        Compute moment-based estimator.
sim_Rs                  Simulate data (R, R0, R1, R2, R3 and R4)
survey_mle              Compute proportion in the survey sample
                        (standard estimator)
update_prevalence       Update prevalence using new case prevalence
                        rates
