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Walters, C., & Ludwig, D. (1994). Calculation of Bayes posterior probability distributions for key population parameters (Vol. 51).
Zusammenfassung: The Bayes posterior probability distribution is a powerful way to represent uncertainty in fisheries stock assessments, and can be calculated for key population and policy parameters of practically any population dynamics model. But the calculation is unwieldy when probabilities are to be assigned to a large grid of parameter combinations. The computational burden can be reduced substantially by analytically integrating over at least two “nuisance parameters” that occur in most assessment models: the observation error variance and the catchability coefficient. This simplification allows the analyst and manager to focus more easily on population parameters (stock size, slope of recruitment curve) that are of direct policy interest.
Schlüsselwörter: Fisch, Fischerei, Statistik, Population, Mathematik, CPUE, VPA, Modell
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Fore, L. S., Karr, J. R., & Conquest, L. L. (1994). Statistical properties of an index of biological integrity used to evaluate water resources (Vol. 51).
Zusammenfassung: The authors determined the statistical properties of the index of biotic integrity (IBI) from electrofishing samples collected from Ohio streams. Although IBI is widely used to evaluate the condition of water resources by biologists and resource managers, expanding its role as a regulatory tool depends on statistical validation of its precision and power. We addressed these issues by constructing an additive variance model for IBI and testing the assumptions of that model directly with a bootstrap resampling algorithm and simulations using field data. Statistical properties of IBI supported the use of standard analysis techniques such as ANOVA for hypothesis testing. We determined with power analysis that IBI can distinguish between five and six nonoverlapping categories of biotic integrity based on a model that includes the effects of measurement error, variability of fish assemblages through time, and statistical interaction of location and time.
Schlüsselwörter: Umweltverschmutzung, Fisch, Elektrofischerei, Methode, Mathematik, Modell, Statistik, ANOVA
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McGarvey, R. (1994). An age-structured open-access fishery model (Vol. 51).
Zusammenfassung: A dynamic model for open-access fisheries is presented. In addition to density dependence in recruitment and fishing effort changing in proportion to the level of profit fishermen earn which characterizes previous open-access models, it incorporates full age structure for the fish stock, lognormal environmental recruitment variability, and gear selectivity. The predator-prey cycling solution of the original Schaefer dynamic model, and subsequent open-access models, persists for these model extensions. Density dependence in recruitment induces greater global stability. Environmental recruitment variability, common in marine populations, is destabilizing in the neighborhood of the open-access equilibrium. Approximating model steady states of effort and catch by the corresponding averages from data time series underlies a new algorithm of parameter evaluation, applied here to an open-access model of the Georges Bank sea scallop (Placopecten magellanicus) fishery.
Schlüsselwörter: fischerei, Population, Mathematik, Modell, Statistik, CPUE
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Wang, Y. G., & Thomas, M. R. (1995). Accounting for individual variability in the von Bertalanffy growth model (Vol. 52).
Zusammenfassung: Estimation of von Bertalanffy growth parameters has received considerable attention in fisheries research. Since Sainsbury much of this research effort has centered on accounting for individual variability in the growth parameters. In this paper we demonstrate that, in analysis of tagging data, Sainsbury's method and its derivatives do not, in general, satisfactorily account for individual variability in growth, leading to inconsistent parameter estimates (the bias does not tend to zero as sample size increases to infinity). The bias arises because these methods do not use appropriate conditional expectations as a basis for estimation.
Schlüsselwörter: Fisch, Statistik, Methode, Vergleich, Wachstum, Bertalanffy, Faben
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Paller, M. H. (1995). Interreplicate Variance and Statistical Power of Electrofishing Data from Low-Gradient Streams in the Southeastern United States (Vol. 15).
Schlüsselwörter: fischerei, statistik, CPUE, methode, elektrofischerei, modell
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Paller, M. H. (1995). Relationships among Number of Fisch Species Sampled, Reach Length Surveyed, and Sampling Effort in South Carolina Coastal Plain Streams (Vol. 15).
Schlüsselwörter: fischerei, Statistik, population, artenzusammensetzung, methode, modell, vergleich, elektrofischerei
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Paller, M. H. (1994). Relationships between Fish Assemblage Structure and Stream Order in South Carolina Coastal Plain Streams (Vol. 123).
Schlüsselwörter: elektrofischerei, fischerei, statistik, artenzusammensetzung, modell, vergleich
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White, G. C. (1996). NOREMARK: Population estimation from mark-resighting surveys (Vol. 24).
Schlüsselwörter: maximum-likeli, Fisch, Mathematik, Vergleich, Modell, capt-recapt, Population, WWW
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Law, P. M. W. (1994). Simulation Study of salmon Carcass Survey Capture-Recapture Methods (Vol. 80).
Schlüsselwörter: capt-recapt, Methode, Vergleich, Modell, Fisch, Statistik
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Tai, C. - F., Hatch, L. U., Masser, M. P., Cacho, O. J., & Hoffmann, D. G. (1994). Validation of a growth simulation model for catfish (Vol. 128).
Schlüsselwörter: Wachstum, Fisch, Modell, Simulation, Mathematik, Statistik
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