mmrm 0.3.11
Bug Fixes
- Previously if a secondary optimizer fails
mmrm
will fail. This is fixed now.
- Previously character covariate variables will make
Anova
fail. This is fixed now.
mmrm 0.3.10
Miscellaneous
- Fix internal test skipping functions for MacOS R.
mmrm 0.3.9
Miscellaneous
- Fix internal test skipping functions for R versions older than 4.3.
mmrm 0.3.8
New Features
Anova
is implemented for mmrm
models and available upon loading the car
package. It supports type II and III hypothesis testing.
- The argument
start
for mmrm_control()
is updated to allow better choices of initial values.
confint
on mmrm
models will give t-based confidence intervals now, instead of the normal approximation.
Bug Fixes
- Previously if the first optimizer failed, the best successful fit among the remaining optimizers was not returned correctly. This is fixed now.
Miscellaneous
- In documentation of
mmrm_control()
, the allowed vcov
definition is corrected to “Empirical-Jackknife” (CR3), and “Empirical-Bias-Reduced” (CR2).
- Fixed a compiler warning related to missing format specification.
- If an empty contrast matrix is provided to
df_md
, it will return statistics with NA
values.
mmrm 0.3.7
New Features
- The argument
method
of mmrm()
now only specifies the method used for the degrees of freedom adjustment.
- Add empirical, empirical Jackknife and empirical bias-reduced adjusted coefficients covariance estimates, which can be specified via the new
vcov
argument of mmrm()
.
- Add residual and between-within degrees of freedom methods.
- Add Kenward-Roger support for spatial covariance structures.
- Add
model.matrix()
and terms()
methods to assist in post-processing.
- Add
predict()
method to obtain conditional mean estimates and prediction intervals.
- Add
simulate()
method to simulate observations from the predictive distribution.
- Add
residuals()
method to obtain raw, Pearson or normalized residuals.
- Add
tidy()
, glance()
and augment()
methods to tidy the fit results into summary tables.
- Add
tidymodels
framework support via a parsnip
interface.
- Add argument
covariance
to mmrm()
to allow for easier programmatic access to specifying the model’s covariance structure and to expose covariance customization through the tidymodels
interface.
Bug Fixes
- Previously
mmrm()
follows the global option na.action
and if it is set other than "na.omit"
an assertion would fail. This is now fixed and hence NA
values are always removed prior to model fitting, independent of the global na.action
option.
- Previously a
model.frame()
call on an mmrm
object with transformed terms, or new data, e.g. model.frame(mmrm(Y ~ log(X) + ar1(VISIT|ID), data = new_data)
, would fail. This is now fixed.
- Previously
mmrm()
always required a data
argument. Now fitting mmrm
can also use environment variables instead of requiring data
argument. (Note that fit_mmrm
is not affected.)
- Previously
emmeans()
failed when using transformed terms or not including the visit variable in the model formula. This is now fixed.
- Previously
mmrm()
might provide non-finite values in the Jacobian calculations, leading to errors in the Satterthwaite degrees of freedom calculations. This will raise an error now and thus alert the user that the model fit was not successful.
Miscellaneous
- Use automatic differentiation to calculate Satterthwaite adjusted degrees of freedom, resulting in 10-fold speed-up of the Satterthwaite calculations after the initial model fit.
- Add an interactive confirmation step if the number of visit levels is too large for non-spatial covariance structures. Use
options(mmrm.max_visits = )
to specify the maximum number of visits allowed in non-interactive mode.
- Removed
free_cores()
in favor of parallelly::availableCores(omit = 1)
.
- The
model.frame()
method has been updated: The full
argument is deprecated and the include
argument can be used instead; by default all relevant variables are returned. Furthermore, it returns a data.frame
the size of the number of observations utilized in the model for all combinations of the include
argument when na.action= "na.omit"
.
- Overall, seven vignettes have been added to the package. All vignettes have a slightly different look now to reduce the size of the overall R package on CRAN.
- The used optimizer is now available via
component(., "optimizer")
instead of previously attr(., "optimizer")
.
mmrm 0.2.2
New Features
- Add support for Kenward-Roger adjusted coefficients covariance matrix and degrees of freedom in
mmrm
function call with argument method
. Options are “Kenward-Roger”, “Kenward-Roger-Linear” and “Satterthwaite” (which is still the default). Subsequent methods calls will respect this initial choice, e.g. vcov(fit)
will return the adjusted coefficients covariance matrix if a Kenward-Roger method has been used.
- Update the
mmrm
arguments to allow users more fine-grained control, e.g. mmrm(..., start = start, optimizer = c("BFGS", "nlminb"))
to set the starting values for the variance estimates and to choose the available optimizers. These arguments will be passed to the new function mmrm_control
.
- Add new argument
drop_visit_levels
to allow users to keep all levels in visits, even when they are not observed in the data. Dropping unobserved levels was done silently previously, and now a message will be given. See ?mmrm_control
for more details.
Bug Fixes
- Previously duplicate time points could be present for a single subject, and this could lead to segmentation faults if more than the total number of unique time points were available for any subject. Now it is checked that there are no duplicate time points per subject, and this is explained also in the function documentation and the introduction vignette.
- Previously in
mmrm
calls, the weights
object in the environment where the formula is defined was replaced by the weights
used internally. Now this behavior is removed and your variable weights
e.g. in the global environment will no longer be replaced.
Miscellaneous
- Deprecated
free_cores()
in favor of parallelly::availableCores(omit = 1)
.
- Deprecated
optimizer = "automatic"
in favor of not specifying the optimizer
. By default, all remaining optimizers will be tried if the first optimizer fails to reach convergence.
mmrm 0.1.5
- First CRAN version of the package.
- The package fits mixed models for repeated measures (MMRM) based on the marginal linear model without random effects.
- The motivation for this package is to have a fast, reliable (in terms of convergence behavior) and feature complete implementation of MMRM in R.
New Features
- Currently 10 covariance structures are supported (unstructured; as well as homogeneous and heterogeneous versions of Toeplitz, auto-regressive order one, ante-dependence, compound symmetry; and spatial exponential).
- Fast C++ implementation of Maximum Likelihood (ML) and Restricted Maximum Likelihood (REML) estimation.
- Currently Satterthwaite adjusted degrees of freedom calculation is supported.
- Interface to the
emmeans
package for computing estimated marginal means (also called least-square means) for the coefficients.
- Multiple optimizers are run to reach convergence in as many cases as possible.
- Flexible formula based model specification and support for standard S3 methods such as
summary
, logLik
, etc.