1ACE 2011

Towards a Conversational Agent Architecture to Favor Knowledge

Discovery in Serious Games

F. Bellotti, R. Berta, A. De Gloria, E. LavagninoELIOS Lab, DIBE, University of Genoa

berta@elios.unige.it

@riccardoberta

ELIOS Lab

2ACE 2011

Definition of Conversational Agent (CA) in Serious GamesRequirementsPresentation of the proposed systemAn example of useFuture research directions

Outlook

3ACE 2011

Conversational Agents (CA)

Non-Player Characters (NPC)controlled by the computer able to dialogue with users in natural languageto increase the situation realism and user involvementusually employed in

virtual world applications (for training, gaming or advertising)

CAs take part in the narrative, playing a specific role: to introduce “back-stories”to assign tasks to playersto reward performance in general, to give information

Our system is focused on instructional dialogues in Serious Games

favoring a player’s acquisition of knowledge on specific topicseasy and efficient writing and maintenance of the CA knowledge

4ACE 2011

CA embodies certain well-defined units of knowledgefor instance, a real policeman is able to give street directions, while a art expert may answer questions about artworks and heritage

CAs are aimed at answering player’s questionsto help in specific knowledge acquisition

The context can be usefully exploited to facilitate the dialogue

sample elements of the context are the appearance of the CA (e.g., uniform, cloths, sex, age), its position, role and game level in which it appears

CA’s knowledge should be easy to edit and maintainalso by people with no specific expertise in automatic dialogue algorithms

Requirements

5ACE 2011

These requirements are not general, but address a specific target of human-content interactions

this kind of CAs may be employed in short dialogues where a player could get knowledge clues about a specific topicthis is a typical need of serious games (like adventures)

The main idea is that such CAs implement a specific serious game mechanism combining:

user knowledge acquisition natural and pleasant interaction

The key element in our view is player knowledge acquisition

not only entertain the player with “real” dialogues

Requirements

6ACE 2011

We have developed a CA system to provide useful information on the basis of the user request to ask player questions in order to stimulate reasoning (e.g., about facts and context)

The system is based on a two level architecture: a strategy level (The Strategy Manager)

it is responsible for managing the high-level aspects of the conversation

a tactical level (The Tactic Manager) it responds to the player’s queries by relying on a combination of simple

syntactical analysis and an statistical procedurea

We are testing the system in two real SGs:SeaGame

for promoting safe maritime behavior in coastal areas a national project funded by Liguria Region (Italy)

Travel in Europe for cultural heritage promotion A EU project funded by Culture 2000 framework

The system

7ACE 2011

Manage the beginning and the end of the conversation.

For instance, SM could welcome the player and invite him to speak, introduce itself, answer to a welcome, etc.

An important first step is the presentation of an overview of the knowledge available by the CA

Change the knowledge set of the tactical level Exploiting information coming from the user answers and queries

Intervene during the conversationproviding help/indications if the conversation is lagging

Terminate the conversation when the CA’s knowledge has been told to the player

The Strategy Manager (SM)

8ACE 2011

Responsible for directly reacting to the user input Not the whole corpus of possible answer documents is analyzed The corpus is structured in answers to different types of questions

Where, When, Who, Why, What, How The five Ws in journalism are the basis for information-gathering

At runtime:when the user inputs a text, the actual question statement is extractedif a question cannot be detected, the TM invites the player to ask questions (giving clues about the topic)otherwise, the question is processed in order to catalog it in one of the W types then the best answer of that type is selectedif no answer shows a sufficient level of precision, the SM intervene for managing the situation

e.g. by outputs an author-defined expression for that situation

The Tactics Manager (TM)

9ACE 2011

Need to allow authors to write dialogue content in a simple, efficient and effective wayIn particular, the author has to prepare:

The set of welcome questions for the SMThe help texts and the trigger conditions through which the

SM proactively intervenes to support the playerThe texts of all the possible answers for the TM

represent the specific knowledge of the CA. every answer has to be tagged with the corresponding W type

The author can also set dependencies among questions one question may enable the player to explore further knowledge

The Authoring Tool

10ACE 2011

Travel in Europe game aims at promoting the cultural heritage of European cities of art

the user explores reconstructed areas of EU cities, while accomplishing missions in a treasure hunts with artistic topicsduring the exploration the player may encounter some CAs with which he can interact in order to get information about the visited areas

We present only one situation (other examples can be found in the paper):

The player has to visit “Palazzo Bianco” (an artistic Renaissance Palace holding a Museum in the Genoa city center) and collect information about the palace and the museum

Use Case (cultural heritage)

11ACE 2011

Player: Is there a museum inside?CA: Yes, there is a museum insidePlayer: At what time does it open?CA: The museum opens at 3 pm.Player: Why is it named Palazzo Rosso?CA: It is named Palazzo Rosso because of its red colorPlayer: When was it built?CA: Palazzo Rosso was built in the 17th CenturyPlayer: Who designed Palazzo Rosso?CA: Architect Pietro Antonio Corradi designed Palazzo RossoPlayer: What can I see inside?CA: You can see a lot of pictures inside

Use Case (cultural heritage)

12ACE 2011

Player: Who are the painters of the pictures exhibited?CA: The painters are Rembrandt and Van DickPlayer: Which are the most important pictures of Rembrandt?CA: The pictures by Rembrandt are the following […]

Use Case (cultural heritage)

13ACE 2011

SGs represent a promising tool for improving instructionConversation can provide an important added value

We propose a system with a focus on instructional dialogues

to favor player acquisition of knowledge on specific topicswe have designed the system and prototyped it in two real examples of SG

Next steps: extensive testing phase with real user system performance improvement in particular in the question handling

type recognition

Implementation of API to include CAs in standard game engine (Unity)Implementation of a GUI for authors

Conclusion and Future Work

14ACE 2011

Thank you!

www.galanoe.euGALA EU NoE on

Serious Games (#galanoe )

@riccardobertawww.elios.dibe.unige.it