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rr-exams

How to avoid schoice questions to receive positive points when two options are selected (one of them right)?

When using the nops_eval function in an exam with only schoice items (5 possible answers), we want the wrong answers to be evaluated like 1/n number of incorrect options. E.g. an item with 3 expoints with a wrong answer should receive: 1/-4 = -.25. However, if a student answers two options in an exam:

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It must not give any positive points... it is a schoice question, so it should evaluate as a wrong answer (i.e. 1/(-4)) even if one of the answers is the right one.

The used options were:

eval_v1 <- nops_eval(register = "nops_eval/pauta_II.csv",
          solutions = "nops_eval/Ex_AEII_MTI_v1_.rds",
          scans = "nops_eval/nops_scan_20210120211740_v1.zip", language = "pt",
          eval = exams_eval(partial = T, negative = T, rule = "false"),
          dir = "eval",
          interactive = T)

If the argument rule = "false2" the final result is the same.

Solution

  • We found the solution... we should set partial = F, negative = -.25. With partial = F, we assure that only full right answers are accepted (as schoice presumes) and with negative = -.25 we assure that all wrong answers are penalized with -.25 times the expoints of each exercise.