问题
Is there a way to directly plot model average summary outputs from MuMIn model.avg() for different variables with confidence bands. Previously I had been using ggplot and ggpredict to plot terms from the actual models, but I haven't been able to find a way to plot the results of the averaged models.
Clearly I can plot the slope and intercept manually, but getting accurate confidence bands and plotting from confint() is not ideal and I have yet to get confidence bands from the intervals that look correct.
library(MuMIn)
#Dummy Data
a <- seq(1:5)
set.seed(1)
b <- sample(1:100,5)
c <- sample(1:100,5)
d <-sample(1:100,5)
df <- data.frame(a,b,c,d)
Dredged <- dredge(lm(a ~ b + c + d, data=df), rank=AIC)
ModelAvg <- model.avg(Dredged, subset=delta<=2)
CI <- confint(ModelAvg, full=T) # get confidence intervals
summary(ModelAvg)
#I want to be able to create a graph for each term from the averaged output with its estimate, SE, and Confidence bands
#Output - I've only left the relevant part of the output, my actual data ends up with 5 component models
#Call:
#model.avg(object = Dredged, subset = delta <= 2)
#Component models:
# df logLik AIC delta weight
#12 4 -1.32 10.63 0.00 0.69
#123 5 -1.10 12.21 1.58 0.31
#Model-averaged coefficients:
#(full average)
# Estimate Std. Error Adjusted SE z value Pr(>|z|)
#(Intercept) 4.933497 1.308953 7.725454 0.639 0.523
#b 0.021946 0.010320 0.048539 0.452 0.651
#c -0.044848 0.012076 0.067954 0.660 0.509
#d -0.002275 0.014081 0.088694 0.026 0.980
回答1:
I'm not quite sure I understand why you are questioning "confint()" output, and the validity of its output is really a distinct question from the graphing question.
To graph the coefficient +/- SE, adj. SE and 95% CIs, try the following. This uses the full model average, since you used the full=T
argument in the CI.
The graph is not the prettiest, but it does the job - let me know if you want a nicer one. I haven't graphed the intercept because the estimates are much greater than the coefficients in this case, but all the data is in an easily graphable format.
library(MuMIn)
#Dummy Data
a <- seq(1:5)
set.seed(1)
b <- sample(1:100,5)
c <- sample(1:100,5)
d <-sample(1:100,5)
df <- data.frame(a,b,c,d)
options(na.action = "na.fail") # needed for dredge to work
Dredged <- dredge(lm(a ~ b + c + d, data=df), rank=AIC)
ModelAvg <- model.avg(Dredged)
mA<-summary(ModelAvg) #pulling out model averages
df1<-as.data.frame(mA$coefmat.full) #selecting full model coefficient averages
CI <- as.data.frame(confint(ModelAvg, full=T)) # get confidence intervals for full model
df1$CI.min <-CI$`2.5 %` #pulling out CIs and putting into same df as coefficient estimates
df1$CI.max <-CI$`97.5 %`# order of coeffients same in both, so no mixups; but should check anyway
setDT(df1, keep.rownames = "coefficient") #put rownames into column
names(df1) <- gsub(" ", "", names(df1)) # remove spaces from column headers
plot with all three error bars (SE, adj. SE, 95% CI)
ggplot(data=df1[2:4,], aes(x=coefficient, y=Estimate))+ #excluding intercept because estimates so much larger
geom_point(size=10)+ #points for coefficient estimates
theme_classic(base_size = 20)+ #clean graph
geom_errorbar(aes(ymin=Estimate-Std.Error, ymax=Estimate+Std.Error), colour ="red", # SE
width=.2, lwd=3) +
geom_errorbar(aes(ymin=Estimate-AdjustedSE, ymax=Estimate+AdjustedSE), colour="blue", #adj SE
width=.2, lwd=2) +
geom_errorbar(aes(ymin=CI.min, ymax=CI.max), colour="pink", # CIs
width=.2,lwd=1)
Which produces the following graph. The red is SE, blue is adj. SE and pink is 95% CIs.
EDIT with nicer graph:
ggplot(data=df1[2:4,], aes(x=coefficient, y=Estimate))+ #again, excluding intercept because estimates so much larger
geom_hline(yintercept=0, color = "red",linetype="dashed", lwd=1.5)+ #add dashed line at zero
geom_errorbar(aes(ymin=Estimate-AdjustedSE, ymax=Estimate+AdjustedSE), colour="blue", #adj SE
width=0, lwd=1.5) +
coord_flip()+ # flipping x and y axes
geom_point(size=8)+theme_classic(base_size = 20)+ ylab("Coefficient")
来源:https://stackoverflow.com/questions/54962119/how-to-plot-from-mumin-model-avg-summary