known fate

questions concerning analysis/theory using program MARK

known fate

Postby amusante » Tue Dec 06, 2005 12:36 pm

I could not find reference to these questions in manual.

In Mark entering weekly known fate data in the two-column staggered entry approach Mark does recognize censored animals the same as kaplan meir correct?

26 0;
25 0;

How could you get Mark to recognize if there was an addition and censor in the same week? Also, if I am looking at multiple years of data and grouping by year, is it valid for same survived animals to be entered in each group and this still be considered annual survival or should I just enter as 1 group and use PIMs to estimate annual survival rates?

Thanks

Tony
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Postby jbruggin » Tue Dec 06, 2005 1:27 pm

If you construct your encounter history appropriately, you should get the same results with the time-dependent model in MARK that you do with the Kaplan-Meier method. If you want to accomodate an addition and censor that occur in the same week, I belived you will have to go with something less than a weekly interval (i.e., the animal has to be at risk at the beginning of the interval).

You may want to check out the following link from Gary White's MARK website to the Burnham and White FW663 class:

http://www.warnercnr.colostate.edu/class_info/fw663/

It provides good discussion of constructing the encounter history, dealing with censors, etc.

John
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