[ACT-R-users] ACT-R software update and some CCL builds

[db30 at andrew.cmu.edu]

The ACT-R software available from the website has been updated.

Here are the two most significant changes relative to the previous
version:

- Retrieval requests now have an additional request parameter called
:rt-value which can be used to temporarily change the value of the
retrieval threshold for that request.

- Production compilation has been updated to allow productions which
use indirect actions, e.g. =goal> g1 or +retrieval> =x, to be composed
when possible.  This is controlled by two new parameters: :cia which
must be set to t to enable composition of indirect actions and :rir
which controls how requests to retrieval style buffers are handled.
The way an indirect action is handled for composition is to first
instantiate it into the specified chunk's slots and values.  Once that
has been done, the normal composition process can be performed.  The
one exception to that is that if the :rir parameter is set to t then
indirect request actions to retrieval style buffers are left as
indirect actions when they are included in the composed production
instead of being instantiated to slots and values.


This version of the software also includes a first test of distributing
ACT-R in a Docker container along with a Jupyter notebook server and
notebook pages with Python code to run the tutorial models and tasks.
Information on that can be found here:

http://act-r.psy.cmu.edu/actr7.x/container_readme.txt

Special thanks to Andrea Stocco for the suggestion and Jupyter examples
and to Don Morrison for the Dockerfile examples which helped to make
this available.



In addition to updating the ACT-R software, I have also made
available some custom builds of Clozure Common Lisp from sources that
fix some issues they haven't rolled into released versions yet.

A Windows version that fixes the problem many people encountered
after a recent Windows update is available at:

http://act-r.psy.cmu.edu/misc/win-ccl.zip

A macOS version of the CCL GUI application that works for macOS 11
is available at:

http://act-r.psy.cmu.edu/misc/ccl.zip


If you have any questions or problems with this update let me know.

Happy Holidays,
Dan

PS
If you're working on a Mac and using ACT-R primarily through the
remote interface, then I've found that the Docker version is
actually faster than running ACT-R natively in SBCL.  That's
because the version of SBCL in the container does not have the
threading performance issue which the Mac specific version does,
and the overhead of running through Docker seems to be less than
that performance hit for threading in the Mac version of SBCL.