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Hi,

I have three groups according to their gender:
1 0 0; (males)
0 1 0; (females)
0 0 1; (sex unknown)

I am using a MS model and would like to make an additive model on the probability of capture: p(sex+time)
whereas I also would like to apply the sex ratio between males and female (0.60 towards males) to the unsex group. That's way the estimates of this group would be intermediate of the males and females estimates.
I tried to create an sex.ratio column in the data and call it in the mark formula but the estimtates for the third group arent good.

In addition, the sex ratio depends of the site (just 2 sites in my data) so it would be great if it would be possible to apply a sex ratio on the unsex group according to the site (I try p(stratum:sex+time) and it's working without the sex ratio)

thanks you very much for your help,

regards,

Florian.

Hi,
I find a solution to apply the sex ratio to the unsex group,
I add a column "sex.ratio" in
multisite.ddl$p
with "1" for te males, "0" for the females and "0.60" for the unsexes

and the following formula works well for a the model Phi(.) ps1(sex+t) ps2(sex+t) Psi(.)

Code: Select all

mark(multisite, multisite.trans.ddl, model.parameters=list(S=list(formula=~1),p=list(formula=~stratum*(sex.ratio+time)),Psi=list(formula=~1)),output=F)

however, I need to implement two differents sex ratio to the unsex according the site
so I m trying the following formula without success because the estimates are wrong when I'm comparing with the output of the same model with Mark but, good news, the estimates of the unsex are intermediate !

Code: Select all

multisite.phi.dot.p.time.psi.dot= mark(multisite, multisite.trans.ddl, model.parameters=list(S=list(formula=~trans),p=list(formula=~stratum1*(sex.ratio.s1+time) : stratum2*(sex.ratio.s2+time)),Psi=list(formula=~1)),output=F)

here, I have created two news column: "stratum1" and "stratum2" in the data frame "multisite.ddl$p" to differentiate the two site
do you find it a correct formula ?

thanks you for your help,
regards,

Florian