[ACT-R-users] Updated ACT-R software release

[db30 at andrew.cmu.edu]

A new version of the ACT-R 7 software is now available from the
ACT-R website: <http://act-r.psy.cmu.edu/software/>.

The new release is primarily to address some issues with running
the software under the newest versions of SBCL and CCL.

There are no significant changes to the architecture with this
release, but there are two new options which may be useful in
some situations.

The first is the addition of motor module commands for using the
numeric keypad on the default keyboard device.  The command
hand-to-keypad (and a manual request with the same name) will move
the model's hand to the numeric keypad with the fingers over the
center row, and the press-key request accepts the keys: clear,
keypad-=, keypad-/, keypad-*, keypad-7, keypad-8, keypad-9,
keypad-minus, keypad-4, keypad-5, keypad-6, keypad-plus, keypad-1,
keypad-2, keypad-3, keypad-0, keypad-period, and enter to hit
the corresponding keys when the hand is on the keypad.

The other is a speculative change to the utility learning credit
assignment mechanism which is being tested as a way to deal with
situations where rewards may be delayed relative to the actions
which should be credited.  Setting :ul to complete (instead of t)
will enable utility learning with the new mechanism.  When :ul
is set to complete then only productions which have "completed"
their actions will receive a reward when one is provided.  If a
production's actions have not completed then it will remain in
the history to receive a reward in the future.

What it means for a production's actions to be completed is that
all of the requests which it makes have been reported as complete
by the modules which received the requests.  Signaling completion
of a request is up to the module that receives the request, and
the current modules have been updated to signal completion of
requests at the same time that they signal a state change back to
being "free" (except in the case of overlapping manual requests
which mark a request as completed when it has finished its last
step even if the overall module is still busy with another
request).


If you have any questions or problems with the new version please
let me know.

Dan