The [C]orrelated [RA]ndom [W]alk [L]ibrary of R functions was
designed for fitting continuous-time correlated random walk (CTCRW)
models with time indexed covariates. The model is fit using the
Kalman-Filter on a state space version of the continuous-time stochastic
movement process. The use case in the estimation of animal movement
paths where the observed locations are determined from Argos or FastLoc
enabled bio-loggers. In addition to the continuous-time component,
{crawl}
was specifically developed to incorporate the measurement
error often associated with these observed locations. Lastly, {crawl}
provides a framework for multiple imputation workflows for incorporation
of model uncertainty.
The original code base and concepts for {crawl}
were developed almost
15 years ago. Much has changed in the world of movement ecology, spatial
statistics, R, bio-logging, and many other fields. In some cases, we’ve
done a fairly good job keeping pace; in other cases, we’ve fallen
behind. We feel it is time for a new approach and will, from now on, be
focusing our development efforts on other packages and methods. We will
continue to maintain {crawl}
, improve the documentation, and ensure
compatibility with dependent packages.
{crawl}
is currently available on CRAN and R >= 4.0 is highly
recommended.
# install latest version of crawl from CRAN
install.packages("crawl")
However, should {crawl}
v 2.3.0 fail to pass CRAN checks it will be
archived on CRAN and all future bug and check fixes will only be
available on this repository and the R-universe repository described in
the next section. So, if you cannot find {crawl}
on CRAN, this has
probably happened.
The latest version of {crawl}
is also available via R-Universe.
# Install crawl from my R-Universe repository
# Enable repository from dsjohnson
options(repos = c(
dsjohnson = 'https://dsjohnson.r-universe.dev',
CRAN = 'https://cloud.r-project.org'))
# Download and install crawl in R
install.packages('crawl')
# Browse the crawl manual pages
help(package = 'crawl')
You can also add the repository to your local list of repositories in
your .Rprofile and this will ensure update.packages()
pulls any new
releases of {crawl}
from R-Universe
#install.packages("usethis")
usethis::edit_r_profile()
# add the following text or replace existing repos option
options(repos = c(dsjohnson = 'https://dsjohnson.r-universe.dev',
CRAN = 'https://cloud.r-project.org'))
A development version of {crawl}
is also available from
GitHub. This version should be used
with caution and only after consulting with package authors.
# install.packages("remotes")
remotes::install_github("NMML/crawl@devel")
This repository is a scientific product and is not official communication of the National Oceanic and Atmospheric Administration, or the United States Department of Commerce. All NOAA GitHub project code is provided on an ‘as is’ basis and the user assumes responsibility for its use. NOAA and DOC have relinquished control of the information and no longer has responsibility to protect the integrity, confidentiality, or availability of the information. Any claims against the Department of Commerce or Department of Commerce bureaus stemming from the use of this GitHub project will be governed by all applicable Federal law. Any reference to specific commercial products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply their endorsement, recommendation or favoring by the Department of Commerce. The Department of Commerce seal and logo, or the seal and logo of a DOC bureau, shall not be used in any manner to imply endorsement of any commercial product or activity by DOC or the United States Government.