05.01.2013 Views

April 2012 Volume 15 Number 2 - Educational Technology & Society

April 2012 Volume 15 Number 2 - Educational Technology & Society

April 2012 Volume 15 Number 2 - Educational Technology & Society

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

Utilization of Test Item<br />

36<br />

33<br />

30<br />

27<br />

24<br />

21<br />

18<br />

<strong>15</strong><br />

12<br />

9<br />

6<br />

3<br />

0<br />

0.49<br />

0.45<br />

0.41<br />

0.37<br />

0.33<br />

0.29<br />

0.25<br />

0.21<br />

Threshold<br />

0.17<br />

0.13<br />

0.09<br />

0.05<br />

0.01<br />

Diagnosys<br />

Figure 14. The use of test items of Diagnosys, OT, and expert for training samples 100<br />

Prediction Accuracy<br />

1<br />

0.98<br />

0.96<br />

0.94<br />

0.92<br />

0.9<br />

0.88<br />

0.86<br />

0.84<br />

0.82<br />

0.8<br />

0.49<br />

0.45<br />

0.41<br />

0.37<br />

0.33<br />

0.29<br />

0.25<br />

0.21<br />

Threshold<br />

0.17<br />

0.13<br />

0.09<br />

0.05<br />

0.01<br />

OT<br />

Expert<br />

Diagnosys<br />

Figure <strong>15</strong>. The prediction accuracy of Diagnosys, OT, and expert for training samples 200<br />

Utilization of Test Item<br />

36<br />

33<br />

30<br />

27<br />

24<br />

21<br />

18<br />

<strong>15</strong><br />

12<br />

9<br />

6<br />

3<br />

0<br />

0.49<br />

0.45<br />

0.41<br />

0.37<br />

0.33<br />

0.29<br />

0.25<br />

0.21<br />

Threshold<br />

0.17<br />

0.13<br />

0.09<br />

0.05<br />

0.01<br />

OT<br />

Expert<br />

Diagnosys<br />

Figure 16. The use of test items of Diagnosys, OT, and expert for training samples 200<br />

Prediction Accuracy<br />

0.8 0.82 0.84 0.86 0.88 0.9 0.92 0.94 0.96 0.98 1<br />

0.02<br />

0.1<br />

0.18<br />

0.26<br />

0.34<br />

0.42<br />

0.5<br />

IRS threshold<br />

0.58<br />

0.66<br />

0.74<br />

0.82<br />

0.9<br />

0.98<br />

Figure 17. The prediction accuracy of the IRS for training samples 10, 50, 100, and 200<br />

OT<br />

Expert<br />

TS=10<br />

TS=50<br />

TS=100<br />

TS=200<br />

83

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!