Millisecond Forums

Thanks Dave. Will try this one and write back if there are issues.

Hi Dave,

Stuck here. Following code is working OK. I want to present 10 random sounds to a respondent, whcih is working fine in this code.

But why is it that the SAME 10 sounds are presented to different respondents.  Why it is not presenting 10 different randomly chosen sounds to different respondents.


<list all>
/ poolsize = 10
/ selectionrate = always
</list>

<list s>
/ items = (values.1S)
/ selectionrate = always
/ selectionmode = random
</list>

<sound 1S>
/ items = sitems
/ playthrough = false
/ select = list.s.nextvalue
</sound>


<item sitems>
/1="1.wav"
/2="2.wav"
/3="3.wav"
/4="4.wav"
/5="5.wav"
/6="6.wav"
/7="7.wav"
/8="8.wav"
/9="9.wav"
/10="10.wav"
/11="11.wav"
/12="12.wav"
/13="13.wav"
/14="14.wav"
/15="15.wav"
/16="16.wav"
/17="17.wav"
/18="18.wav"
/19="19.wav"
/20="20.wav"
</item>

<values>
/ 1S = 1
</values>


<likert NewStudy1>
/ ontrialbegin = [values.1S = list.all.nextindex]      
/ anchors = [1="Extremely pleasant"; 11="Extremely Unpleaant"]
/ stimulusframes = [1 = 1S; 100= 1S;          200= 1S;               300= 1S;               400= 1S;               500= 1S;          600= 1S;               700= 1S;               800= 1S;               900= 1S;               1000= 1S;            1100= 1S;          1200= 1S;            1300= 1S;            1400= 1S;            1500= 1S;            1600= 1S;            1700= 1S;          1800= 1S;            1900= 1S;            2000= 1S;            2100= 1S;            2200= 1S;            2300= 1S;          2400= 1S;            2500= 1S;            2600= 1S;            2700= 1S;            2800= 1S;            2900= 1S;          3000= 1S;            3100= 1S;            3200= 1S;            3300= 1S;            3400= 1S;            3500= 1S;          3600= 1S;            3700= 1S;            3800= 1S;            3900= 1S;            4000= 1S;            4100= 1S;          4200= 1S;            4300= 1S;            4400= 1S;            4500= 1S;            4600= 1S;            4700= 1S;          4800= 1S;            4900= 1S;            5000= 1S;            5100= 1S;            5200= 1S;            5300= 1S;          5400= 1S;            5500= 1S;            5600= 1S;            5700= 1S;            5800= 1S;            5900= 1S;          6000= 1S;            6100= 1S;            6200= 1S;            6300= 1S;            6400= 1S;            6500= 1S;
]
/ fontstyle = ("Arial", 1.4%,true, false, false, false, 5, 0)
/ beginresponseframe = 1
/ anchorwidth = 150
/ recorddata = true
/ response = free
/ numpoints=11
/ position = (50, 55)
</likert>

<block NewStudy1>
/ trials = [1-10= random(NewStudy1)]
/ bgstim = (Q1,qnew, block1)
/ skip = [dropdown.agreement.response == "I do NOT agree to participate in this study"]
/ screencolor = (white)
/ responsemode = correct
/ recorddata = true
</block>

It's the same 10 sounds because you are only sampling from items 1 to 10

<list all>
/ poolsize = 10
/ selectionrate = always
</list>

not from items up to 30.

See https://www.millisecond.com/forums/FindPost26853.aspx again.

when I use poolsize 30 then there is variation of sounds within partipant also across 2 blocks. I want same 10 sounds for one participant across many blocks.

But between particpants these 10 sounds should vary.

That is what the code I gave you does:

https://www.millisecond.com/forums/FindPost26853.aspx

The example selects 5 items out of 30 at random for a given participant, and those 5 items then remain the same for that participant. A different participant will get a different sample of 5 items out of 30, which will then remain constant for that participant.