Dear all,

I'm writing (again!) to ask for help interpreting standard errors of
parameter estimates in OUwie models.

I'm using OUwie to examine how the evolution of bird plumage color varies
across habitat types (my selective regimes) in a tree of 229 tips. I was
hoping to be able to make inferences based on OUMV and OUMVA models, but I
was getting nonsensical theta estimates from those. So I've basically given
up on them for now.

But even looking at theta estimates from OUM models, I'm getting really
large standard errors, often overlapping the estimates from other selective
regimes. So I was wondering what that means exactly. How are these erros
calculated? How much do high errors it limit the biological inferences I
can make? I'm more interested in the relative thetas across regimes than on
the exact values (testing the prediction that birds in darker habitats tend
to adapt to darker plumages than birds in more illuminated habitats).

I have attached a table averaging parameter estimates and errors from
models fitted across a posterior distribution of 100 simmaps for four
traits; and one exemplar fitted model from one trait in one of those
simmaps.

Thanks a lot for any help,


*--*
*Rafael Sobral Marcondes*
PhD Candidate (Systematics, Ecology and Evolution/Ornithology)

Museum of Natural Science <http://sites01.lsu.edu/wp/mns/>
Louisiana State University
119 Foster Hall
Baton Rouge, LA 70803, USA

Twitter: @brown_birds <https://twitter.com/brown_birds>

Attachment: examplemodel.Rdata
Description: Binary data

"","contr","cshd","dors","vent"
"alpha",12.5211974035619,0.109118336288676,0.188269326799061,0.127597860419386
"sigma",0.180045695495247,0.00396667687125656,0.00197418414559043,0.0174191134089773
"theta.nonfor",0.122003341302122,0.242981682496306,0.0401883454304332,0.0480278622048759
"theta.inter",0.122411957974391,0.330086595241058,0.148423104530892,0.315539263124135
"theta.fores",0.132779290334064,0.201704814639995,0.00302560765889108,-0.0271920809202343
"error.alpha",0.0000274105578529269,0.294298534451523,0.270472798858502,0.26541565419898
"error.sigma",0.0990758682811601,0.200146541596876,0.240650337813526,0.196370884887296
"error.theta.nonfor",0.0270532951694773,0.124100699569027,0.0439958864355066,0.215523783597162
"error.theta.inter",0.0117772088364146,0.0726470306166831,0.0271896004588866,0.1258953328922
"error.theta.fores",0.00692620874720748,0.0304814221710456,0.00934452717932142,0.050272790672325
"HL",0.0553578989468505,6.35225209744952,3.68167875428661,5.43227902318834
"HL.height.ratio",0.00195313466537929,0.224119845781518,0.129896808560086,0.191661401065611
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