cpuekapp: Trawl survey based abundance estimation using data sets with...

In fishmethods: Fishery Science Methods and Models

Trawl survey based abundance estimation using data sets with unusually large catches

Description

Calculates the mean cpue after replacing unusually large catches with expected values using the method of Kappenman (1999)

Usage

cpuekapp(x = NULL, nlarge = NULL, absdif = 0.001)

Arguments

x	vector of non-zero trawl catch data.
nlarge	the number of values considered unusually large.
absdif	convergence tolerance

Details

Use function gap to choose the number of unusually large values.

Value

kappmean	list element containing new arithmetic mean.
expectations	list element containing the original observation(s) and expected order statistic(s).

Author(s)

Gary A. Nelson, Massachusetts Division of Marine Fisheries [e-mail]

References

Kappenman, R. F. 1999. Trawl survey based abundance estimation using data sets with unusually large catches. ICES Journal of Marine Science. 56: 28-35.

See Also

gap

Examples

 ## Not run: 
  ## Data from Table 1 in Kappenman (1999)
  data(kappenman)
  cpuekapp(kappenman$cpue,1)
 
## End(Not run)

fishmethods documentation built on April 27, 2023, 9:10 a.m.