| pickCoef {gnm} | R Documentation |
Get the indices for a subset of model coefficients selected via a Tk dialog or by regular expression matching.
pickCoef(object, regexpr = NULL, ...)
object |
a model object. |
regexpr |
character string containing a regular expression. If missing, a Tk dialog will open for coefficient selection. |
... |
arguments to pass on to relimp:::pickFrom. |
A named vector of indices, or NULL.
Regular expression matching is performed using grep with
default settings.
Heather Turner
set.seed(1)
### Use with ofInterest
data(yaish)
## fit the "UNIDIFF" mobility model across education levels
unidiff <- gnm(Freq ~ educ*orig + educ*dest +
Mult(Exp(educ), orig:dest),
family = poisson, data = yaish, subset = (dest != 7))
## set coefficients in first constituent multiplier as 'ofInterest'
ofInterest(unidiff) <- pickCoef(unidiff, "Mult.*educ")
## summarise model, only showing coefficients of interest
summary(unidiff)
## get contrasts of these coefficients
getContrasts(unidiff, ofInterest(unidiff))
### Use to pick out coefficients relating to different groups
data(voting)
## reconstruct counts voting Labour/non-Labour
count <- with(voting, percentage/100 * total)
yvar <- cbind(count, voting$total - count)
## create factors indicating movement in and out of salariat (class 1)
upward <- with(voting, origin != 1 & destination == 1)
downward <- with(voting, origin == 1 & destination != 1)
## fit separate weights for the "socially mobile" groups
socialMobility <- gnm(yvar ~ -1 + Dref(origin, destination,
delta = ~ 1 + downward + upward),
family = binomial, data = voting)
## calculate weights
DrefWeights(socialMobility)