[LON-CAPA-users] correct answer changing to incorrect

[James Mueller]

A student just complained that he solved a problem but later Lon Capa said he was incorrect.  I looked at his submissions and see the following.  From the submissions, it looks like he completed every part of the problem on Nov 21, but on Nov 30, his first incorrect answer for the first part appears to be entered again, and it is listed as the first trial.  I can give him credit for getting this correct, but does anyone have any ideas as to how this might happen?

-Jim Mueller

Sun Nov 21 06:34:31 pm 2010 (EST)Part: 11 (ID 12) Trial not counted  0.0490
 Part: 11  no_unit 
  Sun Nov 21 06:34:33 pm 2010 (EST)Part: 11 (ID 12) Trial 1  0.0490 m
 Part: 11  incorrect 
  Sun Nov 21 06:35:54 pm 2010 (EST)Part: 11 (ID 12) Trial 2  2.0944 m
 Part: 11  approx_ans 
  Sun Nov 21 06:38:14 pm 2010 (EST)Part: 13 (ID 14) Trial not counted  284.8377 m/s
 Part: 13  sig_fail 
  Sun Nov 21 06:38:19 pm 2010 (EST)Part: 13 (ID 14) Trial 1  284.81 m/s
 Part: 13  incorrect 
  Sun Nov 21 06:38:23 pm 2010 (EST)Part: 13 (ID 14) Trial 2  284.84 m/s
 Part: 13  incorrect 
  Sun Nov 21 06:39:19 pm 2010 (EST)Part: 13 (ID 14) Trial 3  45.33 m/s
 Part: 13  approx_ans 
  Sun Nov 21 06:41:29 pm 2010 (EST)Part: 15 (ID 16) Trial 1  6.66 m/s
 Part: 15  approx_ans 
  Tue Nov 30 05:10:17 am 2010 (EST)Part: 11 (ID 12) Trial 1  0.0490 m
 Part: 11  incorrect