About:
HDDM is a python toolbox for hierarchical Bayesian parameter
estimation of the Drift Diffusion Model (via PyMC).
Drift Diffusion Models are used widely in psychology and cognitive
neuroscience to study decision making.
Changes:
-
New and improved HDDM model with the following changes:
-
Priors: by default model will use informative priors
(see http://ski.clps.brown.edu/hddm_docs/methods.html#hierarchical-drift-diffusion-models-used-in-hddm)
If you want uninformative priors, set
informative=False .
-
Sampling: This model uses slice sampling which leads to faster
convergence while being slower to generate an individual
sample. In our experiments, burnin of 20 is often good enough.
-
Inter-trial variablity parameters are only estimated at the
group level, not for individual subjects.
-
The old model has been renamed to
HDDMTransformed .
-
HDDMRegression and HDDMStimCoding are also using this model.
-
HDDMRegression takes patsy model specification strings. See
http://ski.clps.brown.edu/hddm_docs/howto.html#estimate-a-regression-model
and
http://ski.clps.brown.edu/hddm_docs/tutorial_regression_stimcoding.html#chap-tutorial-hddm-regression
-
Improved online documentation at
http://ski.clps.brown.edu/hddm_docs
-
A new HDDM demo at http://ski.clps.brown.edu/hddm_docs/demo.html
-
Ratcliff's quantile optimization method for single subjects and
groups using the
.optimize() method
-
Maximum likelihood optimization.
-
Many bugfixes and better test coverage.
-
hddm_fit.py command line utility is depracated.
|