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OpenSesame not logging whether responses are correct


I'm using OpenSesame to design a simple reaction-time study. It involves participants rapidly judging whether a string of letters is a word or non-word (lexical decision task), by pressing a YES key (letter G) or NO key (letter H).

The problem I'm facing is that the 'logger' item - which I placed immediately after the 'keyboard response' item (allowed responses letters 'g' and 'h') - is not logging whether the response is correct or incorrect. [Please see attached photo for my current set-up]

Under the microsoft excel records, the cell labelled 'correct' consistently logs 'undefined'. [Please see attached photo] I know the excel sheet should reflect either 1 for correct or 0 for incorrect, because it did previously. But I can't seem to figure out why it suddenly isn't doing so now.

Would appreciate soonest help if anyone knows!



  • Hi,
    Did you set correct_response of the judgement_practice object ?


  • edited January 2017

    Hi Elliot,

    I left the correct_response blank of the judgement_practice_object empty, with allowed responses letter 'g' and letter 'h' [please see top screenshot].

    But I specified the correct response for each data entry [please see bottom screenshot, right most column].

    The funny thing is that the experiment does call up the correct response page, and error response page, based on whether the response is accurate. But as mentioned the data file does not log the accuracy in the 'correct' cell?

    Many Thanks,

  • Hi Elliot,

    I realized I changed the label for correct_response to correct_response_practice, so after amending the judgement_practice object it now logs the response accuracy!

    Many Thanks,

  • Hi Samuel,

    how did you manage that each value appears in a separate cell in excel?


  • Hi Micki,

    1 Open Excel
    2 Go to "data"
    3 "open text"
    4 Choose your path
    5 select "separated"
    6 seleft "by comma"
    --> your done

    I would recommend to open your data in a statistics program.
    You will need it for further analyses anyway.
    In SPSS opening the .csv is similar to Excel.

    You're welcome

  • hey, I have used python script instead of keypad icon for response. accuracy variable is coming undefined while test is running ok. help me in setting accuracy.

  • Hi,

    For the accuracy variable to be defined, you need to use the right variable names for the response, the correct response and the correctness of the response. In particular, the response has to be called var.response, the correect response has to be called, var.correct_response, and the variable that indicates whether a specific response was correct or not, should be called var.correct. Based on these variables Opensesame will compute the variable var.accuracy.

    But if you have a variable that indicates whether a trial was correct or not, you can also define your own accuracy variable, all you need to know is the total number of trials and the total number of correct responses.

    Hope this helps,


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