3.4. Generalised linear modeling
The final GLM model for abundance of mature
(stages 4-5)
squid in autumn was as follows:
Catch rate=- 390-0.016
DEPTH +11.1
AVERAGE SAL+2.43
SIN ASPECT+4.9
PROP- GRAVEL (%deviance explained =11%).
Note that the effect of gravel was not originally linear
(df= 2; see)
but inclusion of PROP- GRAVEL2 as well as PROP- GRAVEL did not improve the fit,
so the quadratic term was dropped from the final GLM.