J.D. Nichols David A. Jett 1987 The usefulness of capture-recapture estimators in any field study will depend largely on underlying model assumptions and on how closely these assumptions approximate the actual field situation. Evaluation of estimator performance under real-world field conditions is often a difficult matter, although several approaches are possible. Perhaps the best approach involves use of the estimation method on a population with known parameters. application/pdf 10.2307/1381576 en Oxford Academic A field comparison of nested grid and trapping web density estimators article