1. Reader’s Questioning: Some Hints for Automated Question Generation
José Otero 1, Koto Ishiwa1 , Vicente Sanjosé2
(1) Universidad de Alcalá
28871 Alcalá de Henares
Madrid, Spain
(2) Universitat de València
46071Valencia, Spain
Workshop on the Question Generation Shared Task and Evaluation Challenge
September 25-26, 2008
NSF, Arlington, VA.

2. Introduction
In this presentation we describe some basic components of the mechanism of human question asking.
Questions may be asked with several purposes. This analysis is focused on sincere information-seeking questions (ISQs) asked by humans who process discourse with an understanding goal.

3. Organization of the presentation
Some basic components of human QG
Text-based and knowledge-based questions.
Generation of knowledge-based questions and a taxonomy according to their causes.
Some implications for automated QG.

4. Mechanisms of question generation
Generation of ISQs by humans is triggered by the recognition of anomalies (Graesser and McMahen, 1993).
A knowledge deficit hypothesis and a knowledge clash hypothesis have been considered as alternative mechanisms to recognize these anomalies (Otero and Graesser, 2001)
Where is the nearest bus stop?
Can’t you see water vapor?

5. A goal+obstacle hypothesis
The generation of ISQs may be conceptualized as a process involving a request for information in order to remove obstacles towards a goal
Input Goal
TEXT OBSTACLES MENTAL
REPRESENTATION
Question Asking
REQUEST FOR INFORMATION
TO OVERCOME OBSTACLES

6. Goals and obstacles when reading texts
Readers attempting a mental representation at the
textbase level generate text-based questions
What does isochoric mean?
situation model level generate knowledge-based questions
Do waves move all the water or only what’s on the surface?

7. How are knowledge-based questions generated
How are knowledge-based questions generated? What may we not know about the world?
  What kind of obstacles may be found in building a situation model? What does it take to build a situation model?: three types of inferences during conscious understanding (Trabasso and Magliano, 1996):
Associations provide information about features, properties, relations and, in general, descriptive detail of the entities mentioned in a text
Explanations provide reasons for why something occurs
Predictions include consequences of actions or events and anticipate occurrences.

8. Three types of obstacles found and questions asked
Obstacles in
Result in
Formulated as
Knowing entities
Explaining entities
Knowing the consequences of entities
Association questions
Explanation questions
Prediction questions
i. What? How?
Why?
What happens next?

9. Different reading goals result in different obstacles and different questions

10. Some implications for QG systems
Obstacles to create a mental representation at the textbase level seem to be easier to identify than obstacles to build a situation model. Therefore generation of text-based questions should be easier to implement than the generation of knowledge-based questions.
Generation of knowledge-based questions should depend on the reading goal of the system, i.e., the attempted internal representation.

11. Some implications for QG systems
The relevance of knowledge-based questions depends, at least, on goals and obstacles:
Given a certain input, it depends on the quality of the attempted goal.
Given a certain input and goal, it depends on the importance of the identified obstacle to attain the goal

12. Thanks for your attention

13. Read the description of the following phenomenon carefully, trying to understand it. Sail boats are used since ancient times. Wind collides against the surface of sails that push the boat so that it navigates. However, sail boats are able to navigate against the wind since several centuries ago. When they navigate against the wind sail boats are able to reach speeds up to two times the square root of the wind’s speed at that moment. An appropriate wind to navigate may have a speed of 50 km/h.
State any query or question so that you may correctly answer the questions of the comprehension test next day. (Understanding version)
Calculate the speed of the boat in this case.
State any query or question so that you may correctly solve the problem next day. (Problem solving version)