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scape (version 2.3.5)

getSigmaI: Extract Abundance Index Sigma

Description

Extract the sigma (magnitude of observation noise) that was used in a model, from survey or commercial abundance index data.

Usage

getSigmaI(model, what="s", series=NULL, digits=NULL)

Value

Numeric vector of year-specific sigmas, or a list of such vectors when analyzing multiple series.

Arguments

model

fitted scape model containing element CPUE and/or Survey.

what

which sigma to extract: "c"[ommercial] or "s"[urvey] abundance index.

series

vector of strings indicating which gears or surveys to analyze (all by default).

digits

number of decimal places to use when rounding, or NULL to suppress rounding.

See Also

getN, getSigmaI, getSigmaR, estN, estSigmaI, and estSigmaR extract and estimate sample sizes and sigmas.

scape-package gives an overview of the package.

Examples

Run this code
## Exploring candidate sigmas:

getSigmaI(x.cod)  # sigma used in assessment 0.20
estSigmaI(x.cod)  # model fit implies 0.17

## Multiple series:

getSigmaI(x.oreo, "c")                 # sigma used in assessment
getSigmaI(x.oreo, "c", digits=2)       # rounded
estSigmaI(x.oreo, "c")                 # model fit implies smaller sigma

getSigmaI(x.oreo, "c", series="Series 2-1")  # get one series
estSigmaI(x.oreo, "c", series="Series 2-1")  # estimate one series

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