Testing Non-parametric Methods to Estimate Cod (Gadus morhua) Recruitment in NAFO Divisions 3NO
1993
Paz, J. | Gómez-Larrañeta, Manuel
6 pages, 3 figures, 1 table.
显示更多 [+] 显示较少 [-]Recognizing that non-parametric methods to estimate fish stock recruitment are generally simple and they do not need to be based on ecological hypotheses, four non-parametric methods; the probability transition matrix and three algorithms to estimate recruitment probability density functions were tested on cod (Gadus morhua) data from NAFO Div. 3NO. The transition matrix method was inadequate because the cod stock failed to meet the primary Markovian assumption: the transition probability must be constant and depend only on the previous state. Of the three algorithm methods, the fixed-interval, the New England and the Cauchy, only the New England was appropriate for calculating recruitment with these stock data. A regression coefficient of r = 0.556 (d.f. = 23, P = 0.003) was obtained when the observed data were compared with the estimated. The validity of estimates of future recruitment using the New England algorithm depends on biotic and abiotic environmental conditions being similar in both the pre-recruit and the observation periods.
显示更多 [+] 显示较少 [-]Peer reviewed
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