By derodriguezz - 3/20/2018
Hi everyone!
I'm trying to set 26 trials in which there should be 16 trials of "choice" and 10 trials of another two kinds ("posneg", "arounon"- 5/5). I'm setting the proportions in the selection pool but I always have an unequal quantity of trials between "posneg" and "arounon" (4/6). This is the code i'm using
<block choiceblock>
/trials = [
1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,39,41,43,45,47,49,51 = noreplacenorepeat(choice, choice, arounon, posneg);
2,4,6,8,10,12,14,16,18,20,22,24,26,28,30,32,34,36,38,40,42,44,46,48,50,52 = rate
]
</block>
thanks to all of you
!
|
By Dave - 3/20/2018
+xHi everyone! I'm trying to set 26 trials in which there should be 16 trials of "choice" and 10 trials of another two kinds ("posneg", "arounon"- 5/5). I'm setting the proportions in the selection pool but I always have an unequal quantity of trials between "posneg" and "arounon" (4/6). This is the code i'm using <block choiceblock> /trials = [ 1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,39,41,43,45,47,49,51 = noreplacenorepeat(choice, choice, arounon, posneg); 2,4,6,8,10,12,14,16,18,20,22,24,26,28,30,32,34,36,38,40,42,44,46,48,50,52 = rate ] </block> thanks to all of you !
1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,39,41,43,45,47,49,51 = noreplacenorepeat(choice, choice, arounon, posneg);
you are taking 26 samples
from
1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,39,41,43,45,47,49,51 = noreplacenorepeat(choice, choice, arounon, posneg);
four elements
26 / 4 = 6.5
since there can be no such thing as "half a trial" (.5), you're getting varying result. The math just doesn't work and your selection pool is not set up correctly.
You've defined a 2:1:1 ratio with noreplacenorepeat(choice, choice, arounon, posneg), but you actually want a 16:5:5 ratio.
2:1:1 and 16:5:5 are mathematically not the same.
2:1:1 would be mathematically equivalent to 16:8:8 or 10:5:5, but it is not mathematically equivalent to 16:5:5.
In fact, you cannot simplify 16:5:5 further, because there is no common divisor for 16 and 5. In other words, you actually need to set up your pool like this:
1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,39,41,43,45,47,49,51 = noreplace(choice, choice, choice, choice, choice, choice, choice, choice, choice, choice, choice, choice, choice, choice, choice, choice, arounon, arounon, arounon, arounon, arounon, posneg, posneg, posneg, posneg, posneg);
|
|