Millisecond Forums

Different conditions with one web script license using the batch element

https://forums.millisecond.com/Topic12071.aspx

By ubcparentinglab - 1/13/2014

Hi,

our lab is new to Inquisit. We created different scripts for a study which combines two computer tasks (an IAT and another experiment).

We have a boy and a girl version and furthermore we want to counterbalance the order of the two tasks. The IAT has 2 conditions (bad or good left) and the other experiment has 2 conditions (Load and No Load). This makes in total 16 conditions.

The problem is now that we have 16 scripts but only one web license. I figured out that you can use the batch element to solve this problem. See here:

<batch GroupA>
/subjects = (1 of 16)
/groupassignment = subjectnumber
/file = "1.boyIAT - for IAT first - bad left.iqx"
/file = "1.BOY_NO load_2nd.iqx"
</batch>

<batch GroupB>
/subjects = (2 of 16)
/groupassignment = subjectnumber
/file = "2.boyIAT - for IAT first - bad left.iqx"
/file = "2.BOY_Load_2nd.iqx"
</batch>

<batch GroupC>
/subjects = (3 of 16)
/groupassignment = subjectnumber
/file = "3.boyIAT - for IAT first - good left.iqx"
/file = "3.BOY_NO load_2nd.iqx"
</batch>

<batch GroupD>
/subjects = (4 of 16)
/groupassignment = subjectnumber
/file = "4.boyIAT - for IAT first - good left.iqx"
/file = "4.BOY_Load_2nd.iqx"
</batch>

<batch GroupE>
/subjects = (5 of 16)
/groupassignment = subjectnumber
/file = "5.BOY_NO load_1st.iqx"
/file = "5.boyIAT - for IAT second - bad left.iqx"
</batch>

<batch GroupF>
/subjects = (6 of 16)
/groupassignment = subjectnumber
/file = "6.BOY_Load_1st.iqx"
/file = "6.boyIAT - for IAT second - bad left.iqx"
</batch>

<batch GroupG>
/subjects = (7 of 16)
/groupassignment = subjectnumber
/file = "7.BOY_NO load_1st.iqx"
/file = "7.boyIAT - for IAT second - good left.iqx"
</batch>

<batch GroupH>
/ subjects = (8 of 16)
/groupassignment = subjectnumber
/file = "8.BOY_Load_1st.iqx"
/file = "8.boyIAT - for IAT second - good left.iqx"
</batch>

<batch GroupI>
/subjects = (9 of 16)
/groupassignment = subjectnumber
/file = "9.girlIAT - for IAT first - bad left.iqx"
/file = "9.Girl_NO load_2nd.iqx"
</batch>

<batch GroupJ>
/subjects = (10 of 16)
/groupassignment = subjectnumber
/file = "10.girlIAT - for IAT first - bad left.iqx"
/file = "10.Girl_Load_2nd.iqx"
</batch>

<batch GroupK>
/subjects = (11 of 16)
/groupassignment = subjectnumber
/file = "11.girlIAT - for IAT first - good left.iqx"
/file = "11.Girl_NO load_2nd.iqx"
</batch>

<batch GroupL>
/ subjects = (12 of 16)
/groupassignment = subjectnumber
/file = "12.girlIAT - for IAT first - good left.iqx"
/file = "12.Girl_Load_2nd.iqx"
</batch>

<batch GroupM>
/subjects = (13 of 16)
/groupassignment = subjectnumber
/file = "13.Girl_NO load_1st.iqx"
/file = "13.girlIAT - for IAT second - bad left.iqx"
</batch>

<batch GroupN>
/subjects = (14 of 16)
/groupassignment = subjectnumber
/file = "14.Girl_Load_1st.iqx"
/file = "14.girlIAT - for IAT second - bad left.iqx"
</batch>

<batch GroupO>
/subjects = (15 of 16)
/groupassignment = subjectnumber
/file = "15.Girl_NO load_1st.iqx"
/file = "15.girlIAT - for IAT second - good left.iqx"
</batch>

<batch GroupP>
/ subjects = (16 of 16)
/groupassignment = subjectnumber
/file = "16.Girl_Load_1st.iqx"
/file = "16.girlIAT - for IAT second - good left.iqx"
</batch>

So if we want to send a participant a link and we want this paticipant be in condition 16, we could send him our linkaddress with ending in ?subjectnumber=256

because 256 is a multiply of 16 and refers to condition 16. Right? The same is for the numbers: 4096, 65536, 1048576,...

But how to do it for number 1 (condition 1)?

Is it comprehensible without seeing the actual scripts?


Help would be appreciated a lot!
By Dave - 1/13/2014

For an explanation how condition assignment works (mathematically) see:It's simple modulo arithmetic. Also take note of the /groupassignment attribute. You can also use groupnumber instead of subjectnumber for condition assignment -- details are available in the documentation.
By ubcparentinglab - 1/14/2014

Thanks - although I already read this forum thread I don´t understand how it works.
How can I put different subjects in the condition 1? 
If "The modulo function returns the remainder of the division subjectnumber/condition" is true than only the subject number 16 refers to condition 1.

Where can I find this documentation?
By Dave - 1/14/2014

> If "The modulo function returns the remainder of the division subjectnumber/condition" is true than only the subject number 16 refers to condition 1.

No. 1 modulo 16 equals 1, i.e., the subject will be assigned to condition 1. 17 modulo 16 equals 1. 33 modulo 16 equals 1. And so forth.

By contrast, 16 modulo 16 equals 0, i.e., the subject will receive the 16th condition. 32 modulo 16 equals 0. 48 modulo 16 equals 0. And so forth.

Same for all the other conditions.
By ubcparentinglab - 1/14/2014

Thank you! It makes sense now!