title: An intelligent tutoring system that generates a natural language dialogue using dynamic multi-level planning.
abstract: OBJECTIVE
  The objective of this research was to build an intelligent tutoring system capable of carrying on a natural language dialogue with a student who is solving a problem in physiology. Previous experiments have shown that students need practice in qualitative causal reasoning to internalize new knowledge and to apply it effectively and that they learn by putting their ideas into words.
  
  
  METHODS
  Analysis of a corpus of 75 hour-long tutoring sessions carried on in keyboard-to-keyboard style by two professors of physiology at Rush Medical College tutoring first-year medical students provided the rules used in tutoring strategies and tactics, parsing, and text generation. The system presents the student with a perturbation to the blood pressure, asks for qualitative predictions of the changes produced in seven important cardiovascular variables, and then launches a dialogue to correct any errors and to probe for possible misconceptions. The natural language understanding component uses a cascade of finite-state machines. The generation is based on lexical functional grammar.
  
  
  RESULTS
  Results of experiments with pretests and posttests have shown that using the system for an hour produces significant learning gains and also that even this brief use improves the student's ability to solve problems more then reading textual material on the topic. Student surveys tell us that students like the system and feel that they learn from it. The system is now in regular use in the first-year physiology course at Rush Medical College.
  
  
  CONCLUSIONS
  We conclude that the CIRCSIM-Tutor system demonstrates that intelligent tutoring systems can implement effective natural language dialogue with current language technology.
authors.affiliation: School of Computer Science, Kookmin University, 861-1 Chongnung-Dong, Sungbuk-Ku, Seoul, Republic of Korea.
authors.forename: Chong Woo
authors.initials: CW
authors.lastname: Woo
authors.forename: Martha W
authors.initials: MW
authors.lastname: Evens
authors.forename: Reva
authors.initials: R
authors.lastname: Freedman
authors.forename: Michael
authors.initials: M
authors.lastname: Glass
authors.forename: Leem Seop
authors.initials: LS
authors.lastname: Shim
authors.forename: Yuemei
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yujian
authors.initials: Y
authors.lastname: Zhou
authors.forename: Joel
authors.initials: J
authors.lastname: Michael
mesh_terms: D001185:Artificial Intelligence; D004501:Education, Medical / Q000379:methods*; D006801:Humans; D008037:Linguistics / Q000379:methods*; D010827:Physiology / Q000193:education*; D010934:Planning Techniques; D014584:User-Computer Interface