[R-sig-ME] Interpretation of Posterior distribution produced by MCMCglmm

[Yannis Dim.]

Dear list,

I have a comparative phylogenetic model with a binary response variable, 4
binary explanatory variables as fixed effects and the phylogeny as a random
effect. I would greatly appreciate it if someone could help me interpret
the output of the model, particularly the density plots of (Intercept),
location_selection and material_transport, which I have attached. As you
can see these three variables have a triangular posterior distribution, and
although I have found a few papers of triangular distribution, they talk
about the prior distribution. I haven't found anything about a triangular
posterior distribution. Following is also the output of the model, in case
that helps:

Iterations = 120000001:1319999501
 Thinning interval  = 500
 Sample size  = 2400000

 DIC: 71.74413

 G-structure:  ~phylo

      post.mean  l-95% CI u-95% CI eff.samp
phylo     3.841 1.215e-11    9.991  1567107

 R-structure:  ~units

      post.mean l-95% CI u-95% CI eff.samp
units         1        1        1        0

 Location effects: care01 ~ location_selection +
substrate_modification + material_transport + laying_location_is_food

                        post.mean l-95% CI u-95% CI eff.samp    pMCMC
(Intercept)              -250.852 -568.741   -5.698     1648  < 4e-07 ***
location_selection        246.618    1.747  564.414     1648 0.000358 ***
substrate_modification      6.168    3.514    9.248  1651692  < 4e-07 ***
material_transport        475.747  165.100  706.887     1079    1e-05 ***
laying_location_is_food     0.187   -2.019    2.408  2393680 0.858883
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1


Many thanks in advance,
Yannis Dimopoulos
PhD Student - The University of Hull