On the Population Size Estimation from Dual-record System: Profile-Likelihood Approaches

Motivated by various applications, we consider the problem of homogeneous human population size (N) estimation from Dual-record system (DRS) (equivalently, two-sample capture-recapture experiment). The likelihood estimate from the independent capture-recapture model Mt is widely used in this context though appropriateness of the behavioral dependence model Mtb is unanimously acknowledged. Our primary aim is to investigate the use of several relevant pseudo-likelihood methods profiling N, explicitly for model Mtb. An adjustment over profile likelihood is proposed. Simulation studies are carried out to evaluate the performance of the proposed method compared with Bayes estimate suggested for general capture-recapture experiment by Lee et al. (Statistica Sinica, 2003, vol. 13). We also analyse the effect of possible model mis-specification, due to the use of model Mt, in terms of efficiency and robustness. Finally two real life examples with different characteristics are presented for illustration of the methodologies discussed.