```
# NOT RUN {
## Fit 2-factor CFA to simulated data. Each factor has 9 indicators.
## Specify the item-level model (if NO parcels were created)
item.syntax <- c(paste0("f1 =~ f1item", 1:9),
paste0("f2 =~ f2item", 1:9))
cat(item.syntax, sep = "\n")
## Below, we reduce the size of this same model by
## applying different parceling schemes
## 3-indicator parcels
mod.parcels <- '
f1 =~ par1 + par2 + par3
f2 =~ par4 + par5 + par6
'
## names of parcels
(parcel.names <- paste0("par", 1:6))
# }
# NOT RUN {
## override default random-number generator to use parallel options
RNGkind("L'Ecuyer-CMRG")
parcelAllocation(mod.parcels, data = simParcel, nAlloc = 100,
parcel.names = parcel.names, item.syntax = item.syntax,
std.lv = TRUE, # any addition lavaan arguments
parallel = "snow") # parallel options
## POOL RESULTS by treating parcel allocations as multiple imputations
## Details provided in Sterba & Rights (2016); see ?poolMAlloc.
## save list of data sets instead of fitting model yet
dataList <- parcelAllocation(mod.parcels, data = simParcel, nAlloc = 100,
parcel.names = parcel.names,
item.syntax = item.syntax,
do.fit = FALSE)
## now fit the model to each data set
fit.parcels <- cfa.mi(mod.parcels, data = dataList, std.lv = TRUE)
summary(fit.parcels) # uses Rubin's rules
anova(fit.parcels) # pooled test statistic
class?lavaan.mi # find more methods for pooling results
# }
# NOT RUN {
## multigroup example
simParcel$group <- 0:1 # arbitrary groups for example
mod.mg <- '
f1 =~ par1 + c(L2, L2)*par2 + par3
f2 =~ par4 + par5 + par6
'
## names of parcels
(parcel.names <- paste0("par", 1:6))
parcelAllocation(mod.mg, data = simParcel, parcel.names, item.syntax,
std.lv = TRUE, group = "group", group.equal = "loadings",
nAlloc = 20, show.progress = TRUE)
## parcels for first factor, items for second factor
mod.items <- '
f1 =~ par1 + par2 + par3
f2 =~ f2item2 + f2item7 + f2item8
'
## names of parcels
(parcel.names <- paste0("par", 1:3))
parcelAllocation(mod.items, data = simParcel, parcel.names, item.syntax,
nAlloc = 20, std.lv = TRUE)
## mixture of 1- and 3-indicator parcels for second factor
mod.mix <- '
f1 =~ par1 + par2 + par3
f2 =~ f2item2 + f2item7 + f2item8 + par4 + par5 + par6
'
## names of parcels
(parcel.names <- paste0("par", 1:6))
parcelAllocation(mod.mix, data = simParcel, parcel.names, item.syntax,
nAlloc = 20, std.lv = TRUE)
# }
```

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