Pradel model data

questions concerning analysis/theory using program MARK

Pradel model data

Postby wildlifeduke » Mon Apr 16, 2012 1:33 pm

Hi all,

I am working on obtaining simple recruitment estimates using the Pradel Survival and Recruitment model. However, when I run my data I am obtaining estimates that I know are incorrect based on the survival of my animals. I have taken a look at the capsid data example provided in MARK, but still a bit confused on how to setup my data as the capsid data appears to have individuals entering at different times (i.e., staggered entry). However, my animals all enter at the same time period and only have one group, denoted by 1. I have setup the data in 'reverse order' as needed for the Pradel models and I posted a sample of it below. Any assistance would be greatly appreciated and thank you in advance!

/*Time periods are: 1) 91 d-9 months; 2) 61-90 d; 3) 8-60 d; 4) birth-7 d*/
0001 1;
0001 1;
0111 1;
0011 1;
1111 1;
0001 1;
1111 1;
1111 1;
0001 1;
0011 1;
0011 1;
0001 1;
0111 1;
0011 1;
0011 1;
1111 1;
1111 1;
0111 1;
1111 1;
1111 1;
1111 1;
0111 1;
1111 1;
0111 1;
1111 1;
wildlifeduke
 
Posts: 1
Joined: Wed Apr 11, 2012 2:52 pm

Re: Pradel model data

Postby cooch » Mon Apr 16, 2012 1:40 pm

wildlifeduke wrote:Hi all,

I am working on obtaining simple recruitment estimates using the Pradel Survival and Recruitment model. However, when I run my data I am obtaining estimates that I know are incorrect based on the survival of my animals. I have taken a look at the capsid data example provided in MARK, but still a bit confused on how to setup my data as the capsid data appears to have individuals entering at different times (i.e., staggered entry). However, my animals all enter at the same time period and only have one group, denoted by 1. I have setup the data in 'reverse order' as needed for the Pradel models and I posted a sample of it below. Any assistance would be greatly appreciated and thank you in advance!

/*Time periods are: 1) 91 d-9 months; 2) 61-90 d; 3) 8-60 d; 4) birth-7 d*/
0001 1;
0001 1;
0111 1;
0011 1;
1111 1;
0001 1;
1111 1;
1111 1;
0001 1;
0011 1;
0011 1;
0001 1;
0111 1;
0011 1;
0011 1;
1111 1;
1111 1;
0111 1;
1111 1;
1111 1;
1111 1;
0111 1;
1111 1;
0111 1;
1111 1;


You need to think harder about what Pradel models do, and what 'recruitment' means. The recruitment parameter in a Pradel model is the number of new individuals at time (i+1) per individual alive and in the population at time (i). If you don't mark newly captured individuals at each occasion, then a Pradel model makes no sense, since there is no way to estimate recruitment.
cooch
 
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Joined: Thu May 15, 2003 4:11 pm
Location: Cornell University


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