[ACT-R-users] [Re] ACT-R and Visual attention problem

[db30 at andrew.cmu.edu]

--On Friday, August 20, 2010 4:27 PM +0900 "=?ks_c_5601-1987?B?udrDosf2?=" 
<y3rr0r at etri.re.kr> wrote:

>
>
> Hi,
>
> After reading Dan's first reply about my question, I've studied about how
> to make a new device.
> Then, some questions were occurred from on the start line.
>
> 1. What is a device?
> According to the reference manual, device is the world with which a model
> interacts.
> and it says that hardware like computer can be a device. until here, I
> understood!.
> then, what is a new device Dan said?
> a picture itself can be a new device?
> Or, what Dan said is that I should make a new device interface for a
> picture on a monitor?
>

Conceptually a device is exactly what the manual says: "the world with which
a model interacts".  It provides the visual information to the model from 
the
world and takes the model's motor actions and passes them on to the world.
The built in devices for ACT-R provide the model with a very simple computer
interface as its world.

>From the software perspective the device is any Lisp object which has a
specific set of methods defined for it.  Those methods provide the model 
with
the visual location and visual object chunks that it can see and accept the
motor actions which the model performs.

Thus, if you want a model to be able to see a picture you will have to
create a device which can convert a picture into chunks which the model
can use.  That device will also have to handle any motor actions the model
makes to do what is appropriate for the task.


> 2. In the ppt 'extending-actr'
> To tell the truth, I'm a stranger to the LISP language and
> ACT-R.(ofcourse, I've studied a little about those for several days)
> anyway, so I hope you understand my status...:-)
> I've seen the example(page 24, titled "actually creating and using one).
> But I don't understand that.
> I know it makes several chunk types, and define chunks for several
> figures.
> and install-device.
> Is it all about making a new device?
> I don't understand.
> Please explain how to make a new device.
> What is meaning of making a new device?
>

Page 24 is not an example of how to create any device, just how to
create and use the example abstract device which is described in the
slides that lead up to it (pp. 16-23).  That device just presents the
model with a set of visual chunks which are created in advance by the
modeler (as is done in the example on p. 24) and prints out the model's
motor actions as they occur.  Only the last three steps of the example
on p. 24 are relevant to all devices:  it must be installed, proc-display
tells the model to process the visual scene, and the model needs to be run.

So, to make a new device you will have to decide on some "object" which
you want to use to represent your device and that will be installed for
the model.  That can be essentially anything -- a list, a pathname, a
true Lisp object, or whatever you feel is appropriate to do the work
needed.  Then you will have to write the eight methods required for a
device, as described in those slides, to provide the necessary interface
for the model.

Alternatively, you could attempt to extend one of the built in ACT-R
devices that interface to the specific Lisp GUI systems or the virtual
windows.  However, that can be more difficult than starting from scratch
since it also requires understanding how those devices work.

Either of those is going to require writing Lisp code and an understanding
of how the visual and motor modules of ACT-R operate.  So, before trying
to write a device you will probably want to work through the ACT-R tutorial
to get a solid understanding of the ACT-R basics.  You will probably also
need to work through some Lisp book or tutorial so that you will be able to
write the Lisp code to do what you want.

Dan