Bayesian Programming and Learning for Multi-Player Video Games ...

• Type: prediction is problem of inference or plan recognition from partial observations;
adaptation given what we know is a problem of decision-making under uncertainty.
• Complexity: the complexity of tactical moves has not been studied particularly, as “tactics”
are hard to bound. If taken form the low-level actions that units perform to produce
tactics, the complexity is that of micro-management performed on the whole map and is
detailed in section 4.2. Players and AI build abstractions on top of that, which enables
them to reason about enemy tactics and infer what they should do from only partial
observations. For these reasons, we think that tactics, at this abstract level, can be modeled
as a POMDP* with partial observations of the opponent’s tactics (identifying them from
low-level observations is already an arduous task), actions as our tactics, and transition
probabilities defined by player’s skills and the game state. Our solutions are real-time on
a laptop.
Opponent Strategy
Incomplete
Data
Our Strategy Our Tactics
Unit UnitGroups
Groups
Production planner
and managers
Opponent Tactics Opponent Positions
Our Style
(+ meta)
BayesianUnit
BayesianUnit
BayesianUnit
BayesianUnit
BayesianUnit
BayesianUnit
BayesianUnit
BayesianUnit
Figure 6.1: Information-centric view of the architecture of the bot, the part concerning this
chapter (tactics) is in the dotted rectangle. Dotted arrows represent constraints on what is
possible, plain simple arrows represent simple (real) values, either from data or decisions, and
double arrows represent probability distributions on possible values. The grayed surfaces are
the components actuators (passing orders to the game).
6.1 What are tactics?
6.1.1 A tactical abstraction
In their study on human like characteristics in RTS games, Hagelbäck and Johansson Hagelbäck
and Johansson [2010] found out that “tactics was one of the most successful indicators of
whether the player was human or not”. Tactics are in between strategy (high-level) and micromanagement
(lower-level), as seen in Fig. 4.5. When players talk about specific tactics, they
use a specific vocabulary which represents a set of actions and compresses subgoals of a tactical
goal in a sentence.
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