This documents describes the changes between mice 2.46.0 and mice 3.0.0. Most code written for versions mice 2.12 - mice 2.46.0 should run unchanged. I have tried to minimize the changes to the function arguments, but it was not possible to remain 100% backward compatible. This document outlines the visible changes, and suggests ways how to adapt old code to mice 3.0.
| Argument | 2.46.0 | 3.0.0 |
|---|---|---|
| method | length ncol(data) |
length length(blocks) |
| predictorMatrix | ncol(data) rows and columns |
length(blocks) rows, ncol(data) columns |
| blocks | not defined | new argument |
| visitSequence | integer, arbitrary length |
character, arbitrary length |
| form | character, length ncol(data) |
deprecated |
| formulas | not defined | named list of formulas |
| blots | not defined | named list of alist |
| diagnostics | deprecated | |
| imputationMethod | deprecated, use method |
|
| defaultImputationMethod | deprecated, use defaultMethod |
|
| ... |
No changes were made for the following arguments: data, m, where, post, defaultMethod, maxit, printFlag, seed and data.init.
If blocks is not specified, then each variable is allocated to a separate block. In that case, length(blocks) is identical to ncol(data), and the method in mice 3.0.0 reduces to variable-by-variable imputation, as in mice 2.46.0 and before.
Argument visitSequence may still be specified as integer or numeric, but it will internally be converted into character using the column names in data.
An existing function call to mice using the old form argument may result in an error Argument "formulas" not a list. The advice is to specify the formula as a list, e.g.,
library(mice, warn.conflicts = FALSE)
#> Loading required package: lattice
imp <- mice(nhanes,
formulas = list(hyp ~ bmi,
chl ~ age + hyp + bmi,
bmi ~ age + hyp + chl),
print = FALSE, m = 1, maxit = 1, seed = 1)
imp$formulas
#> $hyp
#> hyp ~ bmi
#>
#> $chl
#> chl ~ age + hyp + bmi
#>
#> $bmi
#> bmi ~ age + hyp + chl