CAPIT: An Intelligent Tutoring System for Capitalisation and Punctuation

ICTG Group

Department of Computer Science

University of Canterbury

Overview Introduction Punctuation/Capitalisation Domain Constraint-Based Modeling (CBM) CAPIT Evaluation Study Results Conclusion

Introduction CAPIT is the second constraint-based ITS Domain is English punctuation and

capitalisation for school children Basic usages of capitals, commas, full-

stops, quotation marks

Introduction First evaluation of CAPIT held in April

2000 Results indicate that children gradually

learned the rules of the domain Children much more motivated by CAPIT

than by traditional pen-and-paper exercises

Punctuation/Capitalisation Domain Check-and-correct: student checks for

errors, if any, and corrects them Completion exercise: student must

punctuate and capitalise an unpunctuated, uncapitalised piece of text

Latter type of exercise chosen

Punctuation/Capitalisation Domain Example:

the teacher said open your books Student submits:

The teacher said, “open your books”. Two errors!

Punctuation/Capitalisation Domain open should be capitalised Period should be inside the quotation Correct Answer:

The teacher said, “Open your books.”

Punctuation/Capitalisation Domain Another example:

theres a bee buzzing past me its taking its honey back to its hive i hope it knows its

way home

Constraint-Based Modelling (CBM) SQL-Tutor is another CBM tutor Domain knowledge represented by a set of

constraints A constraint is a pattern of form <Cr, Cs> If a solution matches the Cr then it must

also match the Cs, else something is wrong

CAPIT Designed for 10-11 year old schoolchildren Interactive system for punctuating and

capitalising text Problems must be designed by a teacher 45 problems and 25 constraints Motivation: points and reward animations

Constraint Database

Problem Database

User Interface

Student Modeller

Pedagogical Module

Feedback Message

Next Problem

Student’s Solution

Violated Constraints

Student Model

CAPIT Constraints cover:

Capitalisation of sentences and names

Ending sentences with a full-stop

Contraction of is and not

Denoting ownership

Direct speech

etc etc

CAPIT A problem consists of a list of words Each word has one or more tags

CAPIT Example:

The SENTENCE-START,NO-PUNC

teacher DEFAULT

said, WORD-PRECEDING-DIRECT-QUOTE,

L-CASE,ONE-PUNC

“Open DIRECT-QUOTE-START,ONE-PUNC

your DEFAULT

books.” DIRECT-QUOTE-ENDING-SENTENCE,

L-CASE,TWO-PUNC

CAPIT A constraint consists of a Cr and a Cs In CAPIT, each constraint also has a

feedback message A Cs is a set of tags A Cr is a regular expression

CAPIT Example:

Cr = {NAME-OF-PERSON}

Cs = ^[%SYMBOLSET%]*[A-Z0-9]

Msg = Each word in a person’s name should start with a capital!

More examples in the paper

Evaluation Study April 2000 Westburn School, Christchurch 28 10-11 year olds working in pairs Four 30-45 minute sessions over 1 month Preliminary evaluation for a more

comprehensive evaluation that followed in June 2000

Evaluation Study Averages per student:

89 attempts at 28 problems

30 seconds per attempt

45 minutes interaction time

21 out of 45 solved problems

7 abandoned problems

181 violated constraints, with feedback on 68

Evaluation Study

y = 0.3737x-0.1673

R2 = 0.687

00.050.1

0.150.2

0.250.3

0.350.4

0 5 10 15 20 25 30 35 40 45 50 55

N

Pro

po

rtio

n o

f V

iola

tio

ns

Conclusion This version of CAPIT had no long-term

student model Next problem was selected randomly Most appropriate error message also

selected randomly (from set of violated constraints)

Conclusion Current version of system has Bayesian

network student model. BN built using data acquired during the

April evaluation Subsequent evaluation of that complete

system held in June 2000 (see IJAIED paper)