Incorporation of Historic catch data into Assessment

Stock assessment should take into account all available data, including 
historic catch information. Two data sets are available
1. Catch-at-age back to 1948 (the ICES 1998 dataset)
2. Total catches back to 1900

#2 will not be handled here, but could be the basis of an extension (e.g. via a 
surplus-production extension (see Eero & MacKenzie MEPS 2011) to the SAM model. 
This could be the basis of work at the regular HAWG meeting

#1 requires
1. Digitisation of data sets - Emma to handle
2. Incorporation into assessment via VPA-format files

Effect of #1 can be evaluated by
1. Comparison of catch observation variances estimated with and without 
historic period data
2. Examination of the historic period residuals on their own

#1 may require
1. Possible modification to SAM tpl to allow for different observation 
variances by period.

Original issue reported on code.google.com by markpayn...@gmail.com on 25 Nov 2011 at 2:39

ices-eg / wg_HAWG

Incorporation of Historic catch data into Assessment #30