Results of 2008 cod aging exchange using randomly selected samples from the first and second quarters of the 2007 NEFSC commercial samples. (A) Age-bias plot, showing the average age attained by the DFO age reader versus the ages attained by the NEFSC age reader. Error bars indicate 95% confidence intervals. (B) Age-frequency table, showing each reader's ages. Numbers in the shaded boxes indicate agreement between the two ages. Numbers above this diagonal indicate fish which were given higher ages by the DFO age reader; those below the shaded boxes were given higher ages by the NEFSC age reader. Total age frequencies are given by age for both readers. (C) Results summary, indicating results for the NEFSC reader relative to each age for the DFO reader.

Species: Cod Test Type: 2008 U.S./Canada Exchange
Sample Source: 2007 Commercial Samples (Q1-2) Stock Area: Georges Bank
Age Reader*: NS vs. BH Date Completed: Spring 2008
Sample Size: 99 CV: 1.80%
Agreement: 88.9% Bowker's test: Not significant
  *The DFO age reader is listed first; this does not imply that reader's ages are expected to be more reliable.


A. Age-Bias Plot

Cod Age-Bias Plot

B. Age-Frequency Table

Age Age (NS)
(BH) 0 1 2 3 4 5 6 7 8 9 10 11 Total
Total 3 37 18 36 3 1 1 99
0
1
2 1 1
3 2 2 4
4 31 31
5 4 18 3 25
6 33 33
7
8 2 2
9 1 1 2
10
11 1 1


C. Results Summary

Age (BH) N N Agreed Percent Agreed Average Age (NS)
2 1 0 0 % 3.00
3 4 2 50 % 3.50
4 31 31 100 % 4.00
5 25 18 72 % 4.96
6 33 33 100 % 6.00
7
8 2 2 100 % 8.00
9 2 1 50 % 8.50
10
11 1 1 100 % 11.00


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