In June we tested 52 participants, which was our minimum. The overall results showed evidence for the null hypothesis, albeit it was not very compelling. We believe that if we test at least 48 more participants (bringing it to a total of 100) our results will be clear enough to draw strong conclusions regarding the competing hypotheses. Therefore we will continue our research this semester. As stated above our goal is to test at least 100 participants (as Bem tested 100 participants in his experiment).We will monitor the Bayes factor as the participants come in and stop whenever the result is clear enough.
The experiment will of course be exactly the same as last semester. Participants will first fill out a questionnaire, then watch a relaxing video and finally perform the actual task on a computer. Due to a randomization issue, our first 52 participants were not yoked, but each received a completely randomized sequence. For purposes of uniformity, we will continue the fully randomized sequence for the new participants.
We also want to attach a paper we have written over the interim results. It is in Dutch.
Interim results (in Dutch)