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Pohlmann, K. (1995). Artenzusammensetzung und Abundanz von Jungfischen in den submersen Makrophytenbeständen vor dem Wollmatinger Ried (Bodensee-Untersee). Konstanz: Universität.
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Hoenig, J. M., Morgan, M. J., & Brown, C. A. (1995). Analysing differences between two age determination methods by tests of symmetry (Vol. 52).
Zusammenfassung: A common problem in fisheries science is the comparison of two methods for obtaining ages of individual animals. The authors suggest that if the overall level of agreement is low between two ageing methods used on the same sample of fish, then one can use a test of symmetry to look for evidence of systematic disagreement. A chi super(2) test is used to determine if the number of fish assigned age i from method 1 and age j from method 2 differs significantly from the number of fish assigned age j from method 1 and age i from method 2. Such a test can also be used to determine the range of nominal ages over which two methods appear to give comparable results.
Schlüsselwörter: Altersbestimmung, Fischerei, Statistik, Methode
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Magnusson, K. G. (1995). An overview of the multispecies VPA -- theory and applications (Vol. 5).
Zusammenfassung: Multispecies virtual population analysis is an attempt to take species interactions into account when assessing the status of fish stocks. It was introduced primarily with the aim of lowering the uncertainty in the natural mortality rate as used in single species VPA and to take account of variability between years and ages by calculating inside the model the part of the mortality rate caused by predation. The output of the MSVPA is therefore – in addition to stock sizes and fishing mortality rates as in single species VPA and intraspecific – and possible species replacement are not considered and neither is predation on larvae and prerecruits. The potential relevance of multispecies models lies in long-term forecasts since short-term forecasts from multi- and single species models differ only slightly. In making long-term forecasts, predicting recruitment is of fundamental importance and the value of MSVPA in throwing light on the processes governing recruitment is limited. MSVPA is concerned primarily with calculating postrecruitment mortalities, and although in principle there is nothing to prevent prerecruitment predation mortalities being calculated, such estimates are not likely to be reliable or useful. Predation on the larval stages can be of major importance in determining recruitment but is not addressed in the MSVPA. Thus, it is quite possible that processes which are not dealt with in the MSVPA are much more important in determining the future of the fisheries. In view of all this uncertainty, it is inevitable that it will be questioned whether multispecies management advice is superior to single species advice.
Schlüsselwörter: vpa, statistik, modell, vergleich, fischerei
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Raymond, M., & Rousset, F. (1995). An exact test for population Differentiation (Vol. 49).
Schlüsselwörter: population, Modell, mathematik, algorithmus, artendifferenzierung, Statistik
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Chan, C. - L., Hoenig, J. M., Dawe, E. G., Brownie, C., & Pollock, K. H. (1995). An Efficient Design for Index-Removal and Change-in-Ratio Estimation of Population Size and Related Parameters. ICES C.M.
Schlüsselwörter: Fisch, mark-recapt, Methode, Statistik, Zippin, Mathematik
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Quartly, G. D. (1995). Altimeter repeat-track analysis -- a comparison of various algorithms for producing the mean profile (Vol. 12).
Zusammenfassung: Sea surface height may be measured by a satellite-borne altimeter and its along-track slope used to infer geostrophic currents. A major difficulty is that, in general, the local geoid and satellite orbit are not known to the accuracy desired. Thus, comparison is often made between repeat flights of an altimeter along fixed ground tracks in order to infer the changes in the currents. In practice, it is convenient to calculate a mean height profile from many repeat passes and use this as a reference, so that individual altimetric profiles yield variations about this mean. It is thus important to derive a high-quality reliable estimate of the altimetric mean in order to minimize the errors in the inferred flows for the individual repeats. This work examines various methods for deriving the mean profile.
Schlüsselwörter: dynamical-oceanography; remote-sensing; satellite-altimetry; sea-level-measurement; geoid-; geostrophic-transport; statistical-analysis; errors-
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-db. (1995). Alles Wichtige über Gateways.
Schlüsselwörter: x.400, dfü, Netzwerk, Grundlagen
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-db. (1995). Alles Wichtige über das Internet.
Schlüsselwörter: Internet, Grundlagen
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Strass, H. (1995). Alles an einem Strang – USB: der universelle Bus für Peripherie-Geräte.
Schlüsselwörter: treiber, hardware, schnittstelle, theorie
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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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