Browsing Published in cooperation with others by Author "Vølstad, Jon Helge"
Now showing items 1-8 of 8
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A framework for improving accuracy in fisheries data used in stock assessments
Pennington, Michael; Vigneau, Joel; Helle, Kristin; Vølstad, Jon Helge (ICES CM documents;2008/N:27, Working paper, 2009) -
Adaptive management of living marine resources by integrating different data sources and key ecological processes (ADMAR): A joint effort by IMR and CEES
Handegard, Nils Olav; Stenseth, Nils Christian; Dankel, Dorothy Jane; Durant, Joël M.; Eikeset, Anne Maria; Enberg, Katja; Hjermann, Dag Ø.; Huse, Geir; Pennington, Michael; Skern-Mauritzen, Mette; Stige, Leif Christian; Subbey, Samuel; Vølstad, Jon Helge (ICES CM documents;2010/R:26 Poster;, Working paper, 2010-09) -
An evaluation of survey design for estimating the food consumption by fish
Bogstad, Bjarte; Pennington, Michael; Vølstad, Jon Helge (ICES CM Documents;1991/D:15, Working paper, 1991)The effect of survey design on the precision of estimates of average fish stomach contents is examined. The contribution to the total variance from within and between tow variability in stomach contents is evaluated, ... -
Analysis of spatial variability of Georges Bank haddock (Melanogrammus aeglefinus) from trawl survey data using a linear regression model with spatial interaction
Polacheck, Tom; Vølstad, Jon Helge (ICES CM Documents;1990/D:36, Working paper, 1990)A regression model with spatially autocorrelated errors is used to test if there is systematic spatial variation across the study area in haddock catch per tow data from the NEFC annual fall survey from 1963 - 1987. A ... -
Assessing the effect of intra-haul correlation and variable density on population estimates from marine surveys
Pennington, Michael; Vølstad, Jon Helge (ICES CM Documents;1991/D:14, Working paper, 1991)In a previous paper (Pennington and Vølstad, Biometrics 47, 1991) it was suggested that reducing the size of the sampling unit generally used in marine surveys could increase the precision of abundance estimates. But if ... -
Optimum size of sampling unit for estimating the density of marine populations
Pennington, Michael; Vølstad, Jon Helge (ICES CM Documents;1989/D:22, Working paper, 1989)Data from several trawling experiments and from some scallop dredge surveys indicate that, within limits, a srnaller sampling unit can be more effective than a larger unit for marine abundance surveys. Taking into account ... -
Self-sampling of the Norwegian Springs Spawning Herring fishery – optimizing data collections to achieve sufficientprecision in stock assessment. ICES CM 2016/O:467 s
Aanes, Sondre; Vølstad, Jon Helge (ICES CM documents;2016/O:467, Lecture, 2016) -
Using acoustic surveys to improve the prediction of bottom trawl indices of abundance
Ona, Egil; Pennington, Michael; Vølstad, Jon Helge (ICES CM documents, Working paper, 1991)