  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.
