Hake Data: problems, solutions and GLM CPUE sensitivity to alternate scenarios
| dc.contributor.author | Fairweather, Tracey | |
| dc.contributor.author | Glazer, Jean | |
| dc.contributor.author | Leslie, Rob | |
| dc.contributor.author | de Decker, Michelle | |
| dc.contributor.author | Johnston, Susan | |
| dc.contributor.author | Butterworth, Doug S | |
| dc.date.accessioned | 2016-04-05T09:43:51Z | |
| dc.date.available | 2016-04-05T09:43:51Z | |
| dc.date.issued | 2009 | |
| dc.date.updated | 2016-04-05T08:07:59Z | |
| dc.description.abstract | The checks carried out on the hake offshore trawl catch and effort data, which provide the basis to split the catches by species and to obtain GLM-standardised CPUE indices of abundance by species, have focused on two separate steps. The first was a re-extract of the data from the original files to check for possible errors in the earlier extracts (this applies to the subset of the data for which size composition information can be unambiguously extracted). The second step was to increase the proportion of the data utilised (and at the same time to check for possible selection biases in the existing sample) by assigning size composition to drags for which this information was not directly available, on the basis of the average for other vessels for which this was available for the area and time at which the fishing concerned took place. The first step revealed a problem with extractions over the last few years which at times for certain vessels had linked the accumulated catch for the day with only the effort for the last trawl of the day, rather than for all trawls that day combined. | en_ZA |
| dc.identifier.apacitation | Fairweather, T., Glazer, J., Leslie, R., de Decker, M., Johnston, S., & Butterworth, D. (2009). <i>Hake Data: problems, solutions and GLM CPUE sensitivity to alternate scenarios</i> University of Cape Town ,Faculty of Science ,Marine Resource Assessment and Management Group. Retrieved from http://hdl.handle.net/11427/18560 | en_ZA |
| dc.identifier.chicagocitation | Fairweather, Tracey, Jean Glazer, Rob Leslie, Michelle de Decker, Susan Johnston, and Doug Butterworth <i>Hake Data: problems, solutions and GLM CPUE sensitivity to alternate scenarios.</i> University of Cape Town ,Faculty of Science ,Marine Resource Assessment and Management Group, 2009. http://hdl.handle.net/11427/18560 | en_ZA |
| dc.identifier.citation | Fairweather, T., Glazer, J., Leslie, R., de Decker, M., Johnson, S. & Butterworth, D. (2009). Hake Data: problems, solutions and GLM CPUE sensitivity to alternate scenarios. MCM/2009/OCT/SWG-DEM/72 | en_ZA |
| dc.identifier.ris | TY - Working Paper AU - Fairweather, Tracey AU - Glazer, Jean AU - Leslie, Rob AU - de Decker, Michelle AU - Johnston, Susan AU - Butterworth, Doug AB - The checks carried out on the hake offshore trawl catch and effort data, which provide the basis to split the catches by species and to obtain GLM-standardised CPUE indices of abundance by species, have focused on two separate steps. The first was a re-extract of the data from the original files to check for possible errors in the earlier extracts (this applies to the subset of the data for which size composition information can be unambiguously extracted). The second step was to increase the proportion of the data utilised (and at the same time to check for possible selection biases in the existing sample) by assigning size composition to drags for which this information was not directly available, on the basis of the average for other vessels for which this was available for the area and time at which the fishing concerned took place. The first step revealed a problem with extractions over the last few years which at times for certain vessels had linked the accumulated catch for the day with only the effort for the last trawl of the day, rather than for all trawls that day combined. DA - 2009 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 2009 T1 - Hake Data: problems, solutions and GLM CPUE sensitivity to alternate scenarios TI - Hake Data: problems, solutions and GLM CPUE sensitivity to alternate scenarios UR - http://hdl.handle.net/11427/18560 ER - | en_ZA |
| dc.identifier.uri | http://hdl.handle.net/11427/18560 | |
| dc.identifier.vancouvercitation | Fairweather T, Glazer J, Leslie R, de Decker M, Johnston S, Butterworth D. Hake Data: problems, solutions and GLM CPUE sensitivity to alternate scenarios. 2009 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/18560 | en_ZA |
| dc.language | eng | en_ZA |
| dc.publisher.department | Marine Resource Assessment and Management Group | en_ZA |
| dc.publisher.faculty | Faculty of Science | en_ZA |
| dc.publisher.institution | University of Cape Town | |
| dc.title | Hake Data: problems, solutions and GLM CPUE sensitivity to alternate scenarios | en_ZA |
| dc.type | Working Paper | en_ZA |
| uct.type.filetype | Text | |
| uct.type.filetype | Image | |
| uct.type.publication | Research | en_ZA |
| uct.type.resource | Research paper | en_ZA |