dsims
Distance Sampling Simulations
Performs distance sampling simulations. 'dsims' repeatedly generates instances of a user defined population within a given survey region. It then generates realisations of a survey design and simulates the detection process. The data are then analysed so that the results can be compared for accuracy and precision across all replications. This process allows users to optimise survey designs for their specific set of survey conditions. The effects of uncertainty in population distribution or parameters can be investigated under a number of simulations so that users can be confident that they have achieved a robust survey design before deploying vessels into the field. The distance sampling designs used in this package from 'dssd' are detailed in Chapter 7 of Advanced Distance Sampling, Buckland et. al. (2008, ISBN-13: 978-0199225873). General distance sampling methods are detailed in Introduction to Distance Sampling: Estimating Abundance of Biological Populations, Buckland et. al. (2004, ISBN-13: 978-0198509271). Find out more about estimating animal/plant abundance with distance sampling at < https://distancesampling.org/>.
dsims
Distance Sampling Simulations
dsims is a package for simulating distance sampling surveys to allow users to optimise survey design for studies with particular properties.
Using dsims
There is currently three vignette within the dsims package to help you get started using dsims:
- GettingStarted: Getting Started with dsims available from the navigation bar at top of the page
- Transition from
DSsimtodsims: under Articles on the navigation bar - Grouped strata: Combining abundance estimates across strata constructed for design purposes; under Articles on the navigation bar
Getting dsims
The easiest way to get dsims is to install it from CRAN within R-studio or the R interface. We endeavour to make all new functionality available on CRAN in a timely manor. However, if you wish to download the development version with the latest updates immediately you can do this using Hadley Wickham's devtools package:
# First, ensure you have a copy of the `devtools` package:
if (!nzchar(system.file(package = "devtools"))) install.packages("devtools")
then install dsims from github:
library(devtools)
install_github("DistanceDevelopment/dsims", build_vignettes = TRUE)
Troubleshooting tip
During installation of packages, you may get the message "These packages have more recent versions available. It is recommended to update all of them. Which would you like to update?" and then a list of packages. We recommend you typically choose the option "CRAN packages only". Note you may then get the message that some packages cannot be installed because they are already loaded. In this case, a solution may be to note which packages these are, to open an R console (rather than R Studio) and to use the Packages | Update packages menu option (or the update.packages function) to update these packages.