This article is from the Backgammon FAQ, by Mark Damish firstname.lastname@example.org with numerous contributions by others.
Ever since Gerry Tesauro finished TD-Gammon, it was only a matter of
time before a neural network program would become available to the
public. That time has come. Fredrik Dahl's masterpiece, Jellyfish, is
a breakthrough for backgammon. Both the checker play and cube action
of the program are at an expert level, making Jellyfish a truly
enjoyable and challenging competitor. In addition the program looks
over your plays and points out when you have made a serious error,
making it extremely valuable for learning purposes.
Jellyfish is run under Windows for the PC. Moves are made with the
mouse, and can be done very quickly and efficiently. The display is
nice and easy to see. Some additional features of the program:
Plays both single games and matches (yes, it understands match
equities). Allows the user to construct positions and save them. Gives
the user the program's evaluation of the equity of a position upon
request, and the evaluation function is surprisingly accurate. Tells
the user when he has made an error in checker play or cube decision,
making the program the most valuable tutor in the world.
In addition, a separate version is expected which will also permit the
user to roll out positions. In the past computer rollouts were always
suspect because the program didn't play well enough so the results
could be very distorted. This is no longer the case, since Jellyfish
definitely plays well enough to handle almost any position adequately.
Results from its rollouts can be trusted, and we will be able to find
the answers to many backgammon questions which we previously did not
For the casual player, Jellyfish provides an excellent opponent and a
way to improve while playing. For the serious student of the game,
this program is an absolute must. Our knowledge of the game is about
to take a quantum leap, and the player who does not have access to
Jellyfish will be left far behind.
JellyFish Tutor 1.2 for MS-Windows. US$ 110.
JellyFish Analyzer 1.0 for MS-Windows US$ 220.
The Analyzer, will in addition to the Tutor, contain a rollout
module It will be release Jan 16 1995. If you own the Tutor,
the Analyzer may be purchased for the difference in price. If
you order the Analyzer before Jan 16 1995, the Tutor will be
shipped immediately, followed by the Analyzer when ready.
EFFECT Software A/S
P.O. Box 56 Skoyen
Please use International Postal Money Order, or Visa. If you use Visa,
send the account number, date of expiration, amount and signature. You
may also send a check, but in that case please add $10 for expenses.
Hardware requirements: 386sx or better
Software requirements: Windows 3.1
The JellyFish programs come on 3.5'' diskettes.
Also available from: The GAMMON PRESS , Carol Joy Cole and The Dansk
The program, and technical support are also available from Larry
Strommen within the USA. Contact:
L. A. Strommen; 6866 Meadow View Dr.; Indianapolis, IN 46226
Tel: (317) 545-0224 E-mail: email@example.com
Fredrik Dahl may be contacted at firstname.lastname@example.org
It should be noted that JellyFish uses a copy protection scheme. The
program requires that you ``confirm'' your installation once a month,
at the first of the month, by inserting the original disk. There are
no limits to how many machines you may install the program on. The DOS
rollout module is not protected at all, although the rollout files
must be created using JellyFish.