Notes on Chapter 9

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*rough notes, need to be polished*

- p. 299: cf. linear vs exponential survival models (goby data), Beverton-Holt vs. survival analysis
- p. 300: note
`*`vs`:`for denoting interactions; notations differ, but R uses`a*b`to signify "main effects of`a`and`b`and their interaction" and`a:b`to signify just the interaction (that is,`a*b`is equivalent to`a+b+a:b`). - p. 301: figure 9.2 was uglified by PUP!

- p. 302: there's a bit of a problem with adding an interaction between two continuous covariates (
`x1*x2`) without adding the quadratic terms (`I(x1^2)+I(x2^2)`at the same time, because the model isn't entirely consistent. - p. 303: note that linear regressions and ANOVA give you different kinds of summary statistics of the same model — e.g. a table of F statistics for the effects of each variable vs. a table of Wald statistics for each parameter.
- p. 304: again note
`f1*f2`is equivalent to`f1+f2+f1:f2` - p. 309: cf SAS
`PROC GENMOD`and`PROC LOGISTIC` - p. 310: I can deal much more thoroughly with fitting type II functional responses via GLM (i.e., using an inverse link), and with the hyperbolic vs exponential function question. See this discussion.
- p. 311: not sure "quasilikelihood" is dealt with with entirely consistently but I may not be able to deal with it sufficiently thoroughly here anyway.
- p. 312 "ratio of deviances" means the deviance difference due to a particular factor divided by the residual deviance (which is an estimate of the overdispersion factor)
- p. 313 I think
`AICtab`can now compute quasi-AIC. I'm still uncomfortable about QAIC, although Richards 2008 (Dealing with overdispersed count data in applied ecology,*J. Appl. Ecology*45:218-227,`doi:10.1111/j.1365-2664.2007.01377.x`) suggests it's really OK.

On to notes on chapter 10

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