Recording the response time for two correct answers in the same trial

[Sean]

Hi, I am in the process of creating an experiment that assesses sustained attention. One of my variables is whether the participant is taking the test alone or with another individual. Everything works smoothly in the alone condition, but it gest tricky when I have two people taking the test. 

The way the test is set up: There are 300 trials in random order that each contain a string of six digits. The participants' task is to respond correctly and as quickly as possible for each trial. If there is the number 4 in the sequence of numbers, they are asked to respond by pressing 1, and if the 4 is absent they are asked to press 2. Then the screen goes blank for about a half of a second and then shows the next sequence of numbers. 

Now I know that the response time is recorded for the individual responding with the 1 and 2, but I need to also be able to record the response time (and correctness) of another participant taking the same test on the same screen using the same keyboard. I got the program to accept 2 responses before moving on to the next sequence, but it only records the first response. For the second participant I asked that they use the keys Z and X the same way I explained for 1 and 2 (Z if there is a 4, X if there is not a 4). 

Is there a way that the program can log the response time and accuracy of both participants taking the test together? In other words, if one participants presses 1 and the other participant presses Z, how can I get the response time for both of the responses? 

Thanks in advance for any help

[David McFarlane]

Take a look at the "Multiple Response Collection" example
downloadable from PST.


-----
David McFarlane
E-Prime training
online: http://psychology.msu.edu/Workshops_Courses/eprime.aspx
Twitter: @EPrimeMaster (twitter.com/EPrimeMaster)

/----
Stock reminder: 1) I do not work for PST. 2) PST's trained staff
take any and all questions at
http://support.pstnet.com/e%2Dprime/support/login.asp , and they
strive to respond to all requests in 24-48 hours -- this is pretty
much their substitute for proper documentation, so make full use of
it. 3) In addition, PST takes questions at their Facebook page
(http://www.facebook.com/pages/Psychology-Software-Tools-Inc/241802160683
), and offers several instructional videos there and on their YouTube
channel (http://www.youtube.com/user/PSTNET ) (no Twitter feed yet,
though). 4) If you do get an answer from PST staff, please extend
the courtesy of posting their reply back here for the sake of others.
\----

[Sheila Bouten]

I have a related question: I have two participants in my experiment using one keyboard to respond to a memory task. For example, if they are shown an image they have seen before, the participant on the left would press "Q" while the participant on the right would press "N". If they hadn't seen the image before, the participant on the left would press "W" while the participant on the right would press "M". My problem is that my code makes it such that if one participant accidentally presses one key twice, their response is recorded twice and the other participant's response is not recorded. This data is thrown out. Is there some code to prevent this by recording only one keystroke from each half of the keyboard? 

Thanks for your help!

[David McFarlane]

Once again, I think you could work out an answer based on the
"Multiple Response Collection" example that you may download from the
PST website. You might enhance that by using two keyboard input
masks on your stimulus object in order to help keep track of which
responses come from which subject.

-----
David McFarlane
E-Prime training
online: http://psychology.msu.edu/Workshops_Courses/eprime.aspx

Twitter: @EPrimeMaster (https://twitter.com/EPrimeMaster)

/----
Stock reminder: 1) I do not work for PST. 2) PST's trained staff
take any and all questions at
http://support.pstnet.com/e%2Dprime/support/login.asp , and they

strive to respond to all requests in 24-48 hours, so make full use of
it. 3) In addition, PST offers several instructional videos on their
YouTube channel (http://www.youtube.com/user/PSTNET ). 4) If you do

get an answer from PST staff, please extend the courtesy of posting
their reply back here for the sake of others.
\----

[francesca ciardo]

Hi everybody,

I  am running an experiment in which two participants are required to response to one of two targets.
Each participants is in charge of one response key of the Response box, one left-sided and one right-sided. In the 50% of the trials the targets appear together on the screen, and thus two responses are required. While for the other 50% of trials only one target is presented, and thus only one response is required (left or right).
I need to collect RTs and accurancy separated for the left and right key of the response box, since they correspond to two different participants.
I already tried to use the Multiple Response collection sample downloaded from psnet support website, but responses are classified, both for RTs and accuracy, as SRbox1 and SRbox 2 according to response speed and not according to response position. How can I solve this problem? Thank you for your help.