[LINK] Artificially Intelligent Game Bots Pass the Turing Test On Turing's Centenary

[tomk]

Quote/ [From: http://www.sciencedaily.com/releases/2012/09/120926133235.htm]

ScienceDaily (Sep. 26, 2012) — An artificially intelligent virtual gamer 
created by computer scientists at The University of Texas at Austin has 
won the BotPrize by convincing a panel of judges that it was more 
human-like than half the humans it competed against.
The competition was sponsored by 2K Games and was set inside the virtual 
world of "Unreal Tournament 2004," a first-person shooter video game. 
The winners were announced this month at the IEEE Conference on 
Computational Intelligence and Games.

"The idea is to evaluate how we can make game bots, which are nonplayer 
characters (NPCs) controlled by AI algorithms, appear as human as 
possible," said Risto Miikkulainen, professor of computer science in the 
College of Natural Sciences. Miikkulainen created the bot, called the 
UT^2 game bot, with doctoral students Jacob Schrum and Igor Karpov.

The bots face off in a tournament against one another and about an equal 
number of humans, with each player trying to score points by eliminating 
its opponents. Each player also has a "judging gun" in addition to its 
usual complement of weapons. That gun is used to tag opponents as human 
or bot.

The bot that is scored as most human-like by the human judges is named 
the winner. UT^2, which won a warm-up competition last month, shared the 
honors with MirrorBot, which was programmed by Romanian computer 
scientist Mihai Polceanu.

The winning bots both achieved a humanness rating of 52 percent. Human 
players received an average humanness rating of only 40 percent. The two 
winning teams will split the $7,000 first prize.

The victory comes 100 years after the birth of mathematician and 
computer scientist Alan Turing, whose "Turing test" stands as one of the 
foundational definitions of what constitutes true machine intelligence. 
Turing argued that we will never be able to see inside a machine's 
hypothetical consciousness, so the best measure of machine sentience is 
whether it can fool us into believing it is human.

"When this 'Turing test for game bots' competition was started, the goal 
was 50 percent humanness," said Miikkulainen. "It took us five years to 
get there, but that level was finally reached last week, and it's not a 
fluke."

The complex gameplay and 3-D environments of "Unreal Tournament 2004" 
require that bots mimic humans in a number of ways, including moving 
around in 3-D space, engaging in chaotic combat against multiple 
opponents and reasoning about the best strategy at any given point in 
the game. Even displays of distinctively human irrational behavior can, 
in some cases, be emulated.

"People tend to tenaciously pursue specific opponents without regard for 
optimality," said Schrum. "When humans have a grudge, they'll chase 
after an enemy even when it's not in their interests. We can mimic that 
behavior."

In order to most convincingly mimic as much of the range of human 
behavior as possible, the team takes a two-pronged approach. Some 
behavior is modeled directly on previously observed human behavior, 
while the central battle behaviors are developed through a process 
called neuroevolution, which runs artificially intelligent neural 
networks through a survival-of-the-fittest gauntlet that is modeled on 
the biological process of evolution.

Networks that thrive in a given environment are kept, and the less fit 
are thrown away. The holes in the population are filled by copies of the 
fit ones and by their "offspring," which are created by randomly 
modifying (mutating) the survivors. The simulation is run for as many 
generations as are necessary for networks to emerge that have evolved 
the desired behavior.

"In the case of the BotPrize," said Schrum, "a great deal of the 
challenge is in defining what 'human-like' is, and then setting 
constraints upon the neural networks so that they evolve toward that 
behavior.

"If we just set the goal as eliminating one's enemies, a bot will evolve 
toward having perfect aim, which is not very human-like. So we impose 
constraints on the bot's aim, such that rapid movements and long 
distances decrease accuracy. By evolving for good performance under such 
behavioral constraints, the bot's skill is optimized within human 
limitations, resulting in behavior that is good but still human-like."

Miikkulainen said that methods developed for the BotPrize competition 
should eventually be useful not just in developing games that are more 
entertaining, but also in creating virtual training environments that 
are more realistic, and even in building robots that interact with 
humans in more pleasant and effective ways./Quote

TomK