NEWS
- Improve handling of formulas. If the original
merMod
has functions specified in the formula, the draw
and wiggle
functions will check for this and attempt to respect these variable transformations. Where this is not possible a warning will be issued. Most common transformations are respected as long as the the original variable is passed untransformed to the model.
- Change the calculations of the residual variance. Previously residual variance was used to inflate both the variance around the fixed parameters and around the predicted values themselves. This was incorrect and resulted in overly conservative estimates. Now the residual variance is appropriately only used around the final predictions
- Rebuilt the readme.md to include new information about new features
- New option for
predictInterval
that allows the user to return the full interval, the fixed component, the random component, or the fixed and each random component separately for each observation
- Fixed a bug with slope+intercept random terms that caused a miscalculation of the random component
- Add comparison to
rstanarm
to the Vignette
- Make
expectedRank
output more tidy
like and allow function to calculate expected rank for all terms at once
- Note, this breaks the API by changing the names of the columns in the output of this function
- Remove tests that test for timing to avoid issues with R-devel JIT compiler
- Remove
plyr
and replace with dplyr
- Fix issue #62
varList
will now throw an error if ==
is used instead of =
- Fix issue #54
predictInterval
did not included random effects in calculations when newdata
had more than 1000 rows and/or user specified parallel=TRUE
. Note: fix was to disable the .paropts
option for predictInterval
... user can still specify for temporary backward compatibility but this should be either removed or fixed in the permanent solution.
- Fix issue #53 about problems with
predictInterval
when only specific levels of a grouping factor are in newdata
with the colon specification of interactions
- Fix issue #52 ICC wrong calculations ... we just needed to square the standard deviations that we pulled
- Fix dependency on
lme4
to ensure compatibility with latest changes.
Bug fixes
- Coerce
dplyr
tbl
and tbl_df
objects to data.frames when they are passed to predictInterval
and issue a warning
- Try to coerce other data types passed to
newdata
in predictInterval
before failing if coercion is unsuccessful
- Numeric stabilization of unit tests by including seed values for random tests
- Fix handling of models with nested random effect terms (GitHub #47)
- Fix vignette images
New Functionality
- Substantial performance enhancement for
predictInterval
which includes better handling of large numbers of parameters and simulations, performance tweaks for added speed (~10x), and parallel backend support (currently not optimized)
- Add support for
probit
models and limited support for other glmm
link functions, with warning (still do not know how to handle sigma parameter for these)
- Add ability for user-specified seed for reproducibility
- Add support for
blmer
objects from the blme
package
- Add a
merModList
object for lists of merMod
objects fitted to subsets of a dataset, useful for imputation or for working with extremely large datasets
- Add a
print
method for merModList
to mimic output of summary.merMod
- Add a
VarCorr
method for merModList
- Add new package data to demonstrate replication from selected published texts on multilevel modeling using different software (1982 High School and Beyond Survey data)
Other changes
- Changed the default
n.sims
for the predictInterval
function from 100 to 1,000 to give better coverage and reflect performance increase
- Changed the default for
level
in predictInterval
to be 0.8 instead of 0.95 to reflect that 0.95 prediction intervals are more conservative than most users need
Future changes
- For the next release (1.0) we are considering a permanent switch to C++ RMVN sampler courtesy of Giri Gopalan 's excellent FastGP package
New Functions
- Provides
predictInterval
to allow prediction intervals from glmer
and lmer
objects
- Provides
FEsim
and REsim
to extract distributions of model parameters
- Provides
shinyMer
an interactive shiny
application for exploring lmer
and glmer
models
- Provides
expectedRank
function to interpret the ordering of effects
- Provides
REimpact
to simulate the impact of grouping factors on the outcome
- Provides
draw
function to allow user to explore a specific observation
- Provides
wiggle
function for user to build a simulated set of counterfactual cases to explore