Windows 7 PsychoPy 3.0.0 Standard Standalone: I want to assign participants to one of two possible conditions randomly. So far I am able to assign participants to a condition manually by using ‘group’ in the info dialog. That is, the conditions for each trial are defined by: $expInfo['group']+".x…

@Nessimon , in a code component you could add the following: # Begin Experiment import random condition = random.choice(('A','B')) Then, your filename in your loop would be called $'Order' + condition + '.xlsx', which would give OrderA.xlsx, or OrderB.xlsx. This will work for Python, but for runnin…

@dvbridges thank you for your suggestion! I had really similar question to @Nessimon and your suggestion worked perfectly for me on my laptop! However, I couldn’t run the experiment on Pavlovia. I may be doing something wrong about Javascript. Windows 10 v2020.1.3. Chrome I have 4 different cond…

@emregurbuz , the error suggests your code has not compiled correctly. You should have had an error message output into the Runner window when you tried to sync your experiment, that will point to where the error has occured.

@dvbridges thank you for the super fast reply! Following is the error message output I received when I tried to sync. [realerror] I guess the problem is with the feedback code. Following is the HTML file that I opened on github: [kod] Also the first lines; [firstlines] Many thanks, Emre

@emregurbuz , its probably because you need to be in a loop to use continue - it moves on to the next loop iteration. In this specific code, you do not need the else continue statement.

@dvbridges I want to give feedback after each trial to participants by showing a red X if they make a mistake. Since I do have my feedback code component in the loop, I thought I had to use “continue” (or equivalent in JS as well). How can I do this in Javascript? Please excuse me if I am asking e…

I see, you could try something like this, putting the code in the relevant tabs: // Begin Experiment red = new util.Color("red"); // create new colors green = new util.Color("green"); // Begin Routine if (resp.corr === 0) { msg = 'X'; text_5.color = red; } else { msg = 'Correct'; text_5.c…

@dvbridges yes I see! So the problem is that I cannot use continue in JS as I use in Python! Thank you very much! I am curious about one last thing. Is it possible to give feedback only on erroneous trials (i.e., “mistake” when person makes an error and “No response” when one does not give any res…

Sure, try the following if (resp.corr === 0) { msg = 'X'; text_5.color = red; } else { msg = ''; }

@dvbridges That worked perfectly! Thank you so much! I have just realized something important. The code that I wrote from your example had just condition A and B. However, I have 4 different conditions. Is the following correct code for 4 different conditions? I couldn’t be sure about JavaScript tr…

@emregurbuz , try: function random_character() { var chars = "ABCD"; return chars.substr( Math.floor(Math.random() * 4), 1); }

Assigning participants randomly to a condition

Builder

bubu September 1, 2020, 7:32am 28

Is there a possibility to randomize people to a condition based on their response on a slider or something else? so based on a response, that they gave before the specific instructions for each condition?

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Assigning participants randomly to a condition

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