FISHERY BULLETIN: VOL. 86, NO. 2 



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Figure 3. — Haddock growth model with an assumed mean hatch-date of 15 April projected through mid-January. An average 

 length of 19.9 cm would have been attained on 01 January, by fisheries science convention the date at which an individual is 

 considered to be 1-year-old. 



inverse regression (Draper and Smith 1966) was 

 performed on the Atlantic cod and haddock 

 grovii;h curves to estabhsh confidence intervals 

 for predicting age from a given standard length. 

 In its reduced form the equation obtained for had- 

 dock was 



X^ _ ln(l - (Xq ± Q.023^(((Xo - 0.2990)2/7.7959) + (1 + l/n))^^^)) 

 Xi -0.0088 



(5) 



where X^^ and Xi = upper and lower confidence 



limits, 

 Xo=l-e-ooo88« and 



n = sample size. 



Figure 6 shows the fitted growth curve bracketed 

 by 95% confidence intervals. 



Performing the same calculations on the At- 

 lantic cod growth curve yielded the relation- 

 ship: 



X„, _ ln(l - (Xq ± 0.022t{{iXo - 0.1918)^/0.9294) + (1 + l/n))^'^)) 



X, 



0.0053 



(6) 



where Zo = l-e-o 0053ft 



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