Michael Mateas

An Oz-centric review of interactive drama and believable agents

Believable agents are autonomous agents that exhibit rich personalities. Interactive dramas take place in virtual worlds inhabited by believable agents with whom an audience interacts. In the course of this interaction, the audience experiences a story. This paper presents the research philosophy behind the Oz Project, a research group at CMU that has spent the last ten years studying believable agents and interactive drama. The paper then surveys current work from an Oz perspective.

Casual Information Visualization: Depictions of Data in Everyday Life

Information visualization has often focused on providing deep insight for expert user populations and on techniques for amplifying cognition through complicated interactive visual models. This paper proposes a new subdomain for infovis research that complements the focus on analytic tasks and expert use. Instead of work-related and analytically driven infovis, we propose casual information visualization (or casual infovis) as a complement to more traditional infovis domains. Traditional infovis systems, techniques, and methods do not easily lend themselves to the broad range of user populations, from expert to novices, or from work tasks to more everyday situations. We propose definitions, perspectives, and research directions for further investigations of this emerging subfield. These perspectives build from ambient information visualization (Skog et al., 2003), social visualization, and also from artistic work that visualizes information (Viegas and Wattenberg, 2007). We seek to provide a perspective on infovis that integrates these research agendas under a coherent vocabulary and framework for design. We enumerate the following contributions. First, we demonstrate how blurry the boundary of infovis is by examining systems that exhibit many of the putative properties of infovis systems, but perhaps would not be considered so. Second, we explore the notion of insight and how, instead of a monolithic definition of insight, there may be multiple types, each with particular characteristics. Third, we discuss design challenges for systems intended for casual audiences. Finally we conclude with challenges for system evaluation in this emerging subfield.

A behavior language for story-based believable agents

A behavior language is a reactive planning language, based on the Oz Project language Hap, designed specifically for authoring believable agents-characters that express rich personality, and that, in this case, play roles in an interactive story called Facade.

A data mining approach to strategy prediction

We present a data mining approach to opponent modeling in strategy games. Expert gameplay is learned by applying machine learning techniques to large collections of game logs. This approach enables domain independent algorithms to acquire domain knowledge and perform opponent modeling. Machine learning algorithms are applied to the task of detecting an opponents strategy before it is executed and predicting when an opponent will perform strategic actions. Our approach involves encoding game logs as a feature vector representation, where each feature describes when a unit or building type is first produced. We compare our representation to a state lattice representation in perfect and imperfect information environments and the results show that our representation has higher predictive capabilities and is more tolerant of noise. We also discuss how to incorporate our data mining approach into a full game playing agent.

Towards Integrating Plot and Character for Interactive Drama

The authors are currently engaged in a three year collaboration to build an interactive story world integrating believable agents and interactive plot. This paper provides a brief description of the project goals and design requirements, discusses the problem of autonomy in the context of story-based believable agents, and describes an architecture that uses the dramatic beat as a s tructural principle to integrate plot and character.

Engineering ethnography in the home

ABSTRACT Intel CorporationJF3-21O2111 NE 25th AvenueHillsboro,OR97124Tel: (503) 264-5766tony_salvador, jean_scholtz, doug_l_sorensen } @ccm.jf.intel.com To inform the design and development of domesticcomputing systems, we performed a pilot ethnographicstudy of the home. The resulting model of domesticactivity shows that the implicit design assumptions of thepersonal computer are inappropriate for the home. Ourmodel suggests that small, integrated, computationalappliances are a more appropriate domestic technologythan the monolithic PC. Keywords ethnography, home computing, ubiquitous computing UNDERSTANDING THE HOMEThe computer industry has a strong interest in sellingcomputer technology into the home. Yet there are fewsources of knowledge on how this technology fits into thehome. Venkatesh [3, 4] provides a valuable analysis ofhome computing diffusion trends. Kraut’s HomeNetproject [2] provides valuable quantitative data regardingInternet use in the home. However, in order to definefuture domestic technologies, we need a more completemodel of daily home life. Towards this end we ran a pilotethnographic study with ten families. During the course ofthis project we developed new data collection methods anda spatial, temporal and social model of the home.

A preliminary poetics for interactive drama and games

Interactive drama has been discussed for a number of years as a new AI-based interactive experience. While there has been substantial technical progress in building believable agents and some technical progress in interactive plot, no work has yet been completed that combines plot and character into a full-fledged dramatic experience. Part of the difficulty in achieving interactive drama is due to the lack of a theoretical framework guiding the exploration of the technological and design issues surrounding it. This paper proposes a theory of interactive drama integrating Laurels Aristotelian structural model with Murrays concept of agency. The resulting theory illuminates the general conditions under which a user will experience agency in any interactive experience and provides design and technology guidance for the particular case of building interactive dramatic worlds.

Rhythm-based level generation for 2D platformers

We present a rhythm-based method for the automatic generation of levels for 2D platformers, where the rhythm is that which the player feels with his hands while playing. Levels are created using a grammar-based method: first generating rhythms, then generating geometry based on those rhythms. Generation is constrained by a set of style parameters tweakable by a human designer. The approach also minimizes the amount of content that must be manually authored, instead relying on geometry components that are included in the level designers tileset and a set of jump types. Our results show that this method produces an impressive variety of levels, all of which are fully playable.

Answer Set Programming for Procedural Content Generation: A Design Space Approach

Procedural content generators for games produce artifacts from a latent design space. This space is often only implicitly defined, an emergent result of the procedures used in the generator. In this paper, we outline an approach to content generation that centers on explicit description of the design space, using domain-independent procedures to produce artifacts from the described space. By concisely capturing a design space as an answer set program, we can rapidly define and expressively sculpt new generators for a variety of game content domains. We walk through the reimplementation of a reference evolutionary content generator in a tutorial example, and review existing applications of answer set programming to generative-content design problems in and outside of a game context.

Tanagra: a mixed-initiative level design tool

Tanagra is a prototype mixed-initiative design tool for 2D platformer level design, in which a human and computer can work together to produce a level. The human designer can place constraints on a continuously running level generator, in the form of exact geometry placement and manipulation of the levels pacing. The computer then fills in the rest of the level with geometry that guarantees playability, or informs the designer that there is no level that meets their requirements. This paper presents the design of Tanagra, a discussion of the editing operations it provides to the designer, and an evaluation of the expressivity of its generator.