I programmed experiments using the self-paced reading function with preview characters. The spaces between words is not displayed correctly on a random basis (different trials each time I run the program). Below are samples to illustrate the problem.
Input:
I like/swimming in lakes/when the water is warm.
Should look like:
I like ________ __ _____ ____ ___ _____ __ ____. (button press)
I like swimming in lakes ____ ___ _____ __ ____. (button press)
I like swimming in lakes when the water is warm.
On random basis, it looks like:
Ilike ________ __ _____ ____ ___ _____ __ ____. (button press)
Ilike swimminginlakes ____ ___ _____ __ ____. (button press)
Ilike swimminginlakes whenthewateriswarm.
The space between words is left out. The problem does not occur on every trial, only a small number of trials.
I am using version 5.05. I have used self-paced reading with prior versions (e.g., 4.0, 4.5) and never had problems. Any suggestions?
I will add that the problem has happened on more than one type of computer, so I know this can’t be a simple incompatibility issue with the laptops we are using. The problem does not occur every time and doesn’t occur on the same trial each time. As I said previously, I never encountered this problem with prior versions of superlab.
You have stumbled upon a bug. When a self-paced reading event is repeated, the spaces within the text are stripped out. You can work around this issue by implementing stimulus lists for your SPR events. This would also significantly decrease the the amount of trial and event items in your experiment. If you need help with this, please let me know.
I will post a case in our internal tracking system and make sure it is brought up to our developers. Thank you for bringing this matter to our attention.
I want to make sure I understand your response. In our study, participants read a passage twice, with the expectation that the second reading is faster. Even though a passage is read twice, we don’t use the same event for the first and second reading. For instance, the first passage has two spr events (“idiom passage 1-2a” and “idiom passage 1-2b”). We set up the program this way because the passages are not always identical during the second reading. Specifically, some passages contain an idiom in the 3rd sentence (trials labeled as idiom trials). For some idiom passages we change the idiom to a similar idiom during the second reading (e.g., “kicked the bucket” could be changed to “bit the dust”). Filler passages don’t have changes during the second reading, but we still use two different events for the first and second readings. Thus, when you say the spr event is repeated, I am not sure what you mean because we don’t repeat spr events. Can you expand?
Given what I just described, I’m not sure how to set this up as a list. Any suggestions would be appreciated.
In your experiment, the issue does not arise from SPR events repeating within a single trial. The issue arises from SPR events repeating throughout the entire scope of the experiment. For example, the event, Idiom Passage 3-2a, is first presented in the block, Trials 1. Eventually, it is again presented in the block, Trials 2. This is the repetition that I am referring to.
In fact, if you only run one of the two blocks from the experiment that you posted, the issue does not occur because the SPR events are never presented a second time.
Technically, you do not have to implement lists. You could simply clone the SPR events that would have been repeated. However, I recommend all users to use stimulus lists if their design allows them.
I see that this thread is not all that recent, but I have a related issue, so I will post it here.
We are presenting an SPR stimulus sentence (using the Space bar) followed by a comprehension question with three possible responses which participants select using the numeral keys: 1, 2, 3. Then, using Feedback they’re told whether they were right or wrong. We use Stimulus Lists for all items, and Tags in the Comprehension question event to identify the correct response (1, 2, or 3). Consequently, the Event ends based on “any response from the participant.”
If participants absentmindedly press the Space bar while the Comprehension question is displayed, they receive the “Incorrect” feedback, as the Space bar was not the Correct answer. In such cases, I’d like to present a different feedback Event (Ooops! Please try again and remember to use the number keys) and then repeat the trial. I can specify the additional “oops” feedback Event, but when the SPR stimulus for the Trial is repeated, the blanks are missing between the underlines/placeholders for each word, appearing as one single underline for the whole sentence.
In the explanation above, you’ve alluded to a work-around using Stimulus Lists, but I haven’t hit on how to do that. I am using Stimulus Lists but still get the problem (bug?).
Could you elaborate on how to get the work-around you have in mind to work?