Hello,
I have a question regarding the randomization for a primed lexical decision task.
For the task I have:
- 5 different types of primes (selected from large banks of images)
- 4 different types of words/nonwords for the lexical decision task (Word Group 1, Word Group 2, Word Group 3, Word Group 4)
& each Word Group contains 10 different words (40 words total)
Ideally, in this experiment there would be 200 trials with each trial being 1 of the 5 prime types and then a unique word.
Currently, my code is able to correctly randomize and present the prime types (40 of each type) and the different categories of words (50 from Group 1, Group, 2, etc.) yet when I look at the precise words/nonwords being presented they vary in amount across the different primes.
For instance, Prime 1 has the nonword "angrop" presented 2 times, Prime 2 has it presented 0 time, Prime 3 - 0 times, Prime 4 - 1 times and Prime 5 - 0 times. In total that means "angrop" was presented 5 times however it is uneven across the different Prime types.
Is there a way to get "angrop" to be presented just once per Prime? Ideally it would be Prime 1 - 1 "angrop", Prime 2 - 1 "angrop", Prime 3 - 1 "angrop", etc.
A shorted modified version of my code:
<item Prime1>
/1 = "stimuli\1"
/2 = "stimuli\2"
...
</item>
*repeated for Prime2-5<item WordGroup1>
/1 = word1
/2 = word2
...
</item>
*repeated for WordGroup2-4<text WG1>
/ items = WordGroup1
/ select = noreplace
</text>
*repeated for WordGroup2-4
<picture P1>
/ items = Prime1
/ select = noreplace
</picture>
*repeated for Prime2-5<trial nonword_P1>
/ stimulustimes = [0=ready; 200=P1; 700=WG1; 950=blank]
/ beginresponsetime = 700
</trial>
<trial wordG2_P1>/ stimulustimes = [0=ready; 200=P1; 700=WG2; 950=blank]/ beginresponsetime = 700</trial> *repeated for each Prime (1-4) and Word Group(1-5), in total 20 types of trials for each combination
<block LDT>
/ trials = [1 = instructions; 2-201=noreplace(
the 20 different types of trials...thus each is presented 10 times)
Thank you so much for your help.