Using SAS or Python to calculate individual point density

[James A. Martin]

Hello Folks,

I am interested in taking a global detection probability function from
program Distance into another program such as SAS or Python and
computing density for each one of my samples (point transects). Has
anyone ever done this? I would like to incorporate numerous covariates
into the model as well. I envision it being able to be dynamic such
that the detection probabilities for each of my intervals can be
changed. Any suggestions would be appreciated!

Thank you.

james martin

mar...@warnell.uga.edu

--
distance-sampling list home page:
http://www.jiscmail.ac.uk/lists/distance-sampling.html
To unsubscribe, go to the home page and click "Join or leave the list",
or email jisc...@jiscmail.ac.uk with the following message body:
leave distance-sampling
Before posting to the list, read the list guidelines at
http://www.jiscmail.ac.uk/files/distance-sampling/
distance-sampling.welcome
Any questions, email the list owner at
distance-sam...@jiscmail.ac.uk
--

[Eric Rexstad]

James (and list):

I'm not completely sure this answers your question, but if you consult
the Distance Users Guide, Appendix - MCDS Engine Reference, you will
learn about a Stats file that is created by Distance. That file can be
accessed, and the global detection function (along with its measures of
uncertainty) can be read by whatever bits and pieces of software you
wish. Searching the PDF for 'stats file' will reveal great amounts of
detail about this file, its specification, and format.

This engine, named "multiple covariate distance sampling" engine is your
friend for fitting the covariates of interest to you in the detection
function.

--
Eric Rexstad
Research Unit for Wildlife Population Assessment
Centre for Research into Ecological and Environmental Modelling
University of St. Andrews
St. Andrews Scotland KY16 9LZ
+44 (0)1334 461833

[James A. Martin]

Eric,

Thanks for the speedy reply. This is leading me down the road I want to
go. I took your lead and poked around about the stats file Can this
engine or file be access outside of Distance? I assume it can be in
Fortran since it is running off of its routines. Does anyone have an
example code for modeling covariates? Thanks again. I apologize in
advance for my ignorance :-) .

jm

mar...@warnell.uga.edu

[Eric Rexstad]

James:

Keep reading that wonderful users guide. You will find a heading
entitled "Running MCDS analyses from outside Distance."

For additional information about accessing this file, you might consult
a technical report I wrote entitled Point and interval estimates of
abundance using multiple covariate distance sampling: An example using
great bustards found at http://eprints.st-andrews.ac.uk/archive/00000447/

Eric Rexstad
Research Unit for Wildlife Population Assessment
Centre for Research into Ecological and Environmental Modelling
University of St. Andrews
St. Andrews Scotland KY16 9LZ
+44 (0)1334 461833

[James A. Martin]

[Eric Rexstad]

James (and list):

I'm not completely sure this answers your question, but if you consult
the Distance Users Guide, Appendix - MCDS Engine Reference, you will
learn about a Stats file that is created by Distance. That file can be
accessed, and the global detection function (along with its measures of
uncertainty) can be read by whatever bits and pieces of software you
wish. Searching the PDF for 'stats file' will reveal great amounts of
detail about this file, its specification, and format.

This engine, named "multiple covariate distance sampling" engine is your
friend for fitting the covariates of interest to you in the detection
function.

James A. Martin wrote:

--
Eric Rexstad
Research Unit for Wildlife Population Assessment
Centre for Research into Ecological and Environmental Modelling
University of St. Andrews
St. Andrews Scotland KY16 9LZ
+44 (0)1334 461833

[James A. Martin]

Eric,

Thanks for the speedy reply. This is leading me down the road I want to
go. I took your lead and poked around about the stats file Can this
engine or file be access outside of Distance? I assume it can be in
Fortran since it is running off of its routines. Does anyone have an
example code for modeling covariates? Thanks again. I apologize in
advance for my ignorance :-) .

jm

mar...@warnell.uga.edu

Eric Rexstad wrote:

[Eric Rexstad]

James:

Keep reading that wonderful users guide. You will find a heading
entitled "Running MCDS analyses from outside Distance."

For additional information about accessing this file, you might consult
a technical report I wrote entitled Point and interval estimates of
abundance using multiple covariate distance sampling: An example using
great bustards found at http://eprints.st-andrews.ac.uk/archive/00000447/

James A. Martin wrote:

Eric Rexstad
Research Unit for Wildlife Population Assessment
Centre for Research into Ecological and Environmental Modelling
University of St. Andrews
St. Andrews Scotland KY16 9LZ
+44 (0)1334 461833