[ACT-R-users] New ACT-R 6.0 release

[db30 at andrew.cmu.edu]

ACT-R 6.0 v1.4 [r1227] is now the current version on the ACT-R
web site.  Here are the changes that I think are the most
significant since the last release:

- More debugging documents and broken models have been added to
the tutorial in units 3, 5, and 7.

- A new request parameter, :mp-value, has been added to the
retrieval buffer.  That allows one to temporarily change the
value of the declarative module's :mp parameter for that request.
That was added as a way to force a perfect match in a model which
uses partial matching, but it could also be used to adjust the
mismatch penalty for other purposes.

- The production compilation trace now includes a specific reason
why a buffer blocks the compilation of two productions.  Here's
an example from the paired-learning model of tutorial unit 7:

Production Compilation process started for ENCODE-ARG1
  Buffer VISUAL prevents composition of these productions
   because the first production makes a request and the second production 
harvests the chunk.
  Production READ-ARG1 and ENCODE-ARG1 cannot be composed.

- A new command, with-parameters, has been added which allows
one to temporarily set model parameters before executing
some code and have the original parameter settings restored
upon completion of that code.  Full details are in the manual,
but here's a simple example to show how it can be used:

(with-parameters (:v t :trace-detail high :act t)
  (run 10))

- There's a new directory included with the sources called
user-loads.  Like several other of the included directories, all
of the .lisp files in that directory will be loaded automatically
when load-act-r-6.lisp is loaded.  This one differs from the
others in that it does not have any of the ACT-R source files in
it and it will be the last one processed.  Therefore, it is safe
to put a model file in there to have it loaded with the rest of
the system.


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

Dan