cochran.calc.ss: Estimates Cochran discard rate and required sample sizes

In noaa-garfo/discaRd: Cochran bycatch estimation

Estimates Cochran discard rate and required sample sizes

Description

This function estimates the discard rate using the Cochran ratio estimator and returns the mean rate as well as estimates of uncertainty and required sample sizes for a target CV

Usage

cochran.calc.ss(df, n_trips, n_obs, CV_targ = NA)

Arguments

df	dataframe where each row is a trip. Requires LINK1, BYCATCH, KALL naming convention
n_trips	Number of total trips
CV_targ	target CV

Value

observed sample size needed for target CV

References

Wiley: Sampling Techniques, 3rd Edition - William G. Cochran. (n.d.). Available from http://www.wiley.com/WileyCDA/WileyTitle/productCd-047116240X.html [accessed 1 August 2016].

Wigley SE, Rago PJ, Sosebee KA, Palka DL. 2007. The Analytic Component to the Standardized Bycatch Reporting Methodology Omnibus Amendment: Sampling Design, and Estimation of Precision and Accuracy (2nd Edition). US Dep. Commer., Northeast Fish. Sci. Cent. Ref. Doc. 07-09; 156 p

Examples

cochran.calc.ss

noaa-garfo/discaRd documentation built on April 17, 2025, 10:32 p.m.