RITEL: Spoken and Interactive Question-Answering System

RITEL: Spoken and Interactive Question-Answering System

A spoken and interactive QA system that helps a user to find an answer to his question, spoken or written, in a collection of documents.

Target users and customers

Question-answering is an end-user application. The purpose is to go beyond the traditional way of retrieving information through search engines. Our system is interactive, with both a speech (phone or microphone) and text (web) interface.

Application sectors

QA system can be viewed as a direct extension of search engines. They allow a user to ask questions in natural language.


There are different ways to go beyond standard retrieval systems such as search engines. One of them is to offer the users different ways to express their query: some prefer to use speech to express a query, while others prefer written natural language. Another way is to allow the user to interact with the system.

The Ritel system aims at integrating a dialog system and an open-domain information retrieval system to allow a human to ask a general question (f.i. « Who is currently presiding the Senate?’’ or « How did the price of gas change for the last ten years?’’) and refine his research interactively.

A human-computer dialog system analyses and acts on the user requests depending on the task at hand, the previous interactions and the user’s behaviour. Its aim is to provide the user with the information being sought while maintaining a smooth and natural interaction flow.

The following example illustrates the kind of possible interaction with the Ritel system:

[S] Hi, Ritel speaking! What is your first question?
[U] who built the Versailles Castle
[S] Your search is about Versailles Castle and built. The answer is Louis XIII. Do you want to ask another question?
[U] in which year
[S] 1682, according to the documents I had access to. Another question?
[U] Who designed the garden
[S] The following items are used for searching: Versailles, gardens and designed. André Le Nôtre. Anything else?

The dialog system is comprised of a component for user utterance analysis, a component for dialog management, and a component for interaction management. The system for information retrieval and question-answering is tightly integrated within it. The user interface can be phone-based or web-based for written interaction.

Technical requirements:

PC with Linux platform.

Conditions for access and use:

Available for licensing on case-by-case basis




Contact details:

Sophie Rosset

TLP Group
B.P. 133
91403 Orsay Cedex