Pick combined with randomizeNoMoreThan

[aliona]

Dear Jeremy,

I have been using the Pick function to have my items presented in 3 blocks separated by 2 breaks. The critical and the filler items are well randomized, but sometimes they appear in long sequences of same-answer trials for the post-sentence question (e.g., 4-5 with a ‘yes’-answer followed by 4-5 with a ‘no’-answer).

Is there a way I could combine the Pick function and maybe randomizeNoMoreThan function to specify that I don’t want to have, say, more than 3 same-answer trials regardless of whether they’re critical or filler (which is specified in a column called “match” with “yes” and “no” values in it)?

Thanks in advance for your help!
Aliona

P.S: here are my Pick function and sequence just in case.

function Pick(set,n) {
    assert(set instanceof Object, "First argument of pick cannot be a plain string" );
    n = Number(n);
    if (isNaN(n) || n<0)
        n = 0;
    this.args = [set];
    this.runSet = null;
    set.remainingSet = null;
    this.run = arrays => {
        if (this.runSet!==null) return this.runSet;
        const newArray = [];
        if (set.remainingSet===null) {
        if (set.runSet instanceof Array) set.remainingSet = [...set.runSet];
        else set.remainingSet = arrays[0];
    }
        for (let i = 0; i < n && set.remainingSet.length; i++)
            newArray.push( set.remainingSet.shift() );
    this.runSet = [...newArray];
    return newArray;
}
}
    function pick(set, n) { return new Pick(set,n); }
        
        critical = randomize("critical")
        fillers = randomize("filler");

PennController.Sequence("demographics","etc",
                        rshuffle(pick(critical,8),pick(fillers,11)),"break",
                        rshuffle(pick(critical,8),pick(fillers,11)),"break",
                        rshuffle(pick(critical,8),pick(fillers,11)),
                        "etc");

• This topic was modified 2 years, 8 months ago by aliona.

[Jeremy]

Hi Aliona,

The Sequence command and the related functions only care about the trials’ labels: if you yes-answer and no-answer trials share the same labels, you won’t be able to control their distribution. I suggest you include the yes/no bit of information in the trials’ labels, eg "critical-yes"/"critical-no" and "filler-yes"/"filler-no"

The pick function will pick the N next trials from a set: when you do pick(critical,8) and critical was set to randomize("critical"), it will pick 8 trials from a randomized set of all the trials labeled “critical”. Then you pass that to rshuffle, so those 8 trials will be interspersed with trials labeled “filler” in the order in which they were picked from critical

You could do that, in which case two critical-yes trials would always be separated by a critical-no, a filler-yes and a filler-no trial:

criticalyes = randomize("critical-yes")
criticalno = randomize("critical-no")
fillersyes = randomize("filler-yes")
fillersno = randomize("filler-no")

Sequence("demographics","etc",
         rshuffle(pick(criticalyes,4),pick(fillersyes,6),pick(criticalno,4),pick(fillersno,5)),"break",
         rshuffle(pick(criticalyes,4),pick(fillersyes,5),pick(criticalno,4),pick(fillersno,6)),"break",
         rshuffle(pick(criticalyes,4),pick(fillersyes,6),pick(criticalno,4),pick(fillersno,5)),
         "etc")

Don’t forget to add -yes/-no to your trials’ labels, and make sure the 5/6 match the number of different types of trials you have (I went with 17 filler-yes trials and 16 filler-no trials, for a total of 33 filler trials)

Jeremy

[aliona]

Hi Jeremy,

it worked out perfectly! Thanks for the help.

Aliona

[Author]

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