1. Mass Producing Example- Tracing Tutors Bruce McLaren Human-Computer Interaction Institute Carnegie Mellon University

2. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 What is Mass Production? Many learning situations require repetition of similar problems, but authoring many similar Example-Tracing Tutors is hard –It is time-consuming to demonstrate individual problems –Inconsistency between problems is often introduced Examples: –Practice fraction addition problems in a math class –Drill on proper use of articles in a language class CTAT mass production allows us to use a single demonstration as the basis for many tutored problems of the same type

3. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Step 1: Enter variables into the template

4. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Save a copy of your existing graph

5. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Insert variables in the start state Close the Behavior Recorder Open the newly saved BRD in a text editor Work backwards from StartStateEnd replacing constants with variables.

6. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 NotePropertySet StartProblem 1416 NotePropertySet InterfaceAction firstNumGiven UpdateTextArea 1

7. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 NotePropertySet StartProblem 1416 NotePropertySet InterfaceAction firstNumGiven UpdateTextArea 1

8. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 NotePropertySet StartProblem 1416 NotePropertySet InterfaceAction firstNumGiven UpdateTextArea %(num1Given)%

9. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 firstNumGiven UpdateTextArea %(num1Given)% Enter variables for all four text areas. Save your BRD. Open it in the Behavior Recorder.

10. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Add variables for input matching

11. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006

12. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Modify hints to include variables

13. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Save your file

14. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Step 2: Create a problems table

15. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Create a problems table

16. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Create a problems table (continued)

17. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Step 3: Input problems into problems table

18. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Input problems into problems table

19. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Input problems into problems table Save the problems table

20. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Step 4: Merge Problems

21. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Merge problems

22. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Merge problems (continued)

23. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Step 5: Test and Revise Launch both the Student Interface and Behavior Recorder Open individual mass-produced problems Test them for accuracy and completeness If necessary, revise the problems table and/or template BRD

24. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Conclusion Mass Production allows us to generate many tutored problems of the same type Issues to be aware of: –Tutored problems must have exactly the same graph structure to be represented in one problems file –Not all fraction addition problems are alike, e.g., 1/2 + 1/2 doesn’t have the same problem solving structure as 1/4 + 1/6 –Be careful to use the full “%(“ and “)%” variable representation. Easy to forget the closing “)%” Let’s try it out!

25. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Hands-On Assignment #2 Mass produce several fraction addition tutors –Use the “Mass Production Guide” hand-out as an aid –Go to the directory…/Projects/Examples/Exercise2-MassProduction –Use the following files in this directory: a completed user interface (i.e., “fractionAddition.fla”), a completed BRD file (i.e., “1-2+1-3.brd”) and a partially completed BRD template file (i.e., “1-2+1-3- BRDTemplate.brd”) –Extend the partially completed BRD template file and mass produce tutors for: 1/2 + 1/3 1/3 + 1/5 1/4 + 1/5 1/6 + 1/7 Thought experiment: Will this BRD template mass produce tutors for any fractions? If not, what are its limits?

26. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 Differences in Fractions Fraction Addition Problems Same Denoms, e.g., 1/2 + 1/2 One denom is a multiple of the other, e.g., 1/2 + 1/4 Different denoms, one is not a multiple of the other, e.g., 1/2 + 1/3 Simplification required, e.g., 1/3 + 5/12 Simplification not required, e.g., 1/2 + 1/4 Simplification required, e.g., 1/7 + 2/12 Simplification not required, e.g., 1/2 + 1/3 Structure varies -- what to do? - Different templates for diff. problem classes - Hints as variables And this doesn’t include whole number results!

27. PSLC Summer School July-August, 2006 © Vincent Aleven & Bruce McLaren, 2006 THE END (Of “Mass Producing Example-Tracing Tutors”)