fishmethods (version 1.3-0)

tag_model_avg: Model Averaging for Instantaneous Rates Tag Return Models

Description

Calculates model averaged estimates of instantaneous fishing, natural and total mortality, and survival rates for instantaneous rates tag return models (Hoenig et al. (1998) and Jiang et al. (2007)).

Usage

tag_model_avg(..., global = NULL)

Arguments

...

model object names separated by commas

global

specify global model name in quotes. If the global model is the first model included in the list of candidate models, this argument can be ignored.

Value

• List containing model summary statistics, model-averaged estimates of fishing, natural, tag, and total mortality, and survival and their weighted and uncondtional standard errors .

Details

Model estimates are generated from functions irm_cr and irm_h. Averaging of model estimates follows the procedures in Burnham and Anderson (2002). Variances of parameters are adjusted for overdispersion using the c-hat estimate from the global model : sqrt(var*c-hat). If c-hat of the global model is <1, 69="" 75="" then="" c-hat="" is="" set="" to="" 1.="" the="" used="" calculate="" quasi-likelihood="" aic="" and="" aicc="" metrics="" for="" each="" model="" (see="" page="" in="" burnham="" anderson(2002)).="" qaicc="" differences="" among="" models="" are="" calculated="" by="" subtracting="" of="" from="" with="" smallest="" value.="" these="" akaike="" weights="" following="" formula="" on="" anderson="" (2002).="" weighted="" average="" standard="" error="" parameter="" estimates="" summing="" product="" model-specific="" weight="" estimate="" across="" all="" models.="" an="" unconditional="" also="" sqrt(sum(QAICc wgt of model i * (var of estimate of model i +(estimate of model i - avg of all estimates)^2))).

References

Burnham, K. P. and D. R. Anderson. 2002. Model selection and multimodel inference : A Practical Information-Theorectic Approach, 2nd edition. Spriner-Verlag, New York, NY. 488 p.

See Also

irm_h irm_cr

Examples

## This is a typical specification, not a working example
tag_model_avg(model1,model2,model3,model4,model5,model6,model7,global="model7")