Path: utzoo!attcan!uunet!cs.utexas.edu!tut.cis.ohio-state.edu!pt.cs.cmu.edu!cat.cmu.edu!jps
From: jps@cat.cmu.edu (James Salsman)
Newsgroups: comp.ai
Subject: Re: ADVICE NEEDED - MACHINE FOR EXPERT SYS. Development
Message-ID: <5695@pt.cs.cmu.edu>
Date: 29 Jul 89 04:50:03 GMT
References: <442@cwjcc.CWRU.Edu>
Distribution: na
Organization: Carnegie Mellon
Lines: 75

In article <442@cwjcc.CWRU.Edu> hathi@colima.UUCP (Kamal Hathi) writes:
> I am looking to buy a machine for expert system development in an
> corporate environment.

I wish people would say what kind of ES they want to write
so those of us that don't have real jobs can figure out
effective methods, point people to the appropriate
literature, and research new ways to do what is wanted.
How can a University prepare engineers for effectiveness in
industry and commerce if industry and commerce don't say
what they would like an engineer to know?

> A LISP machine may not be appropriate and hence I was considering an
> UNIX workstation which could run a good LISP environment and a decent
> shell.

What do you mean by "decent shell?"  And if you could find a
"decent shell," why would you need Lisp?

> I would like some recommendations on which machine to buy. The budget is
> going to be around $20,000.

Who told you you had to do ES development in Lisp?  Lisp is
a good teaching language for AI, but it's as slow as a dog
for finished systems unless you can afford a Lisp Machine -- and you can't.
Don't even think about Lispm coprocessor boards unless you
enjoy working with multiple personality disorder in hardware.

> What are your opinions regarding the SUN 386i ?? I a considering
> this one actively.

A glorified PC.  You'll spend less money on hardware and
gain valuable experience if you swallow your pride and
develop for a regular old PC.  For that kind of hardware, C
compilers have the best development environments these days.
(PC C development environs are much nicer than Unix's unless
you are surrounded by gurus and grad students.)  The old
640K memory limitation is a thing of the past with all the
cool extended memory boards and a C with a malloc that knows
about EMS.

If you need a higher-level symbol system, there are two options.

  (1) Backward chaining with Prolog (Borland makes a cool PC
      Prolog with a development environment that is a bit crouded
      but managable), and

  (2) Forward Chaining with production systems (OPS-83 is
      from around here, it's development environment is too
      sparse, IMHO, but the code is lightning fast.)

If you aren't into batch coding, the Mac II can run some
really neat knowledge engineering shells like Nexpert,
Knowledge Foo, etc., but if you use them you are stuck with
their interface.  Sometimes it's a problem, especially with
the freaked out obtrusive-user-interface-technology in some
of the more expensive products.  If the demo screen print
looks too good to be true, it is probably worse than you
could ever imagine.  Get the manual before you buy.

In the long run, Macs are a lot less costly than Unix boxes
(especially in set-up time), and the same software for Macs
cost less than for Unix.  The Mac/PC price differential has
reached a competitive equilibrium.  (You get what you pay for.)

The only reason that you would need Unix is for VM, and if
you need more than 5 megs RAM, I doubt you'll get far with $20K.

:James

Disclaimer:  I don't speak for the university.  Neither do
   I write, type, sing, or sign for the University.
-- 

:James P. Salsman (jps@CAT.CMU.EDU)