Millisecond Forums

Recording information that corresponds to a trial item

https://forums.millisecond.com/Topic11117.aspx

By DanielB - 8/28/2013





Hi everybody, I’m new to Inquisit, and was hoping the community could help me solve this problem


For my experiment, I’m showing participants a pair of
integers and asking them to determine which integer is larger. The pairs are
presented in random order.


For each trial, I want Inquisit to record the difference between the numbers in the pair and
their ratio on the data sheet in addition to the stimulus number (for example, if the stimulus
is “6       9”, the distance would be 3 and
the ratio would be 1.5).

I've made a list of differences and ratios that corresponds to my stimulus numbers. I have also made two columns in the data sheet for this data, but I'm not sure how to tell Inquisit to record the correct item from that list for each trial.


For reference, here are the bits of script that I think are relevant


<list distancetag>
/ items = [number3]
</list>

<item number3>
/1 = "1"
/2 = "1"
/3 = "1"
/4 = "1"
/5 = "1"
/6 = "2"
/7 = "1"
/8 = "2"
/9 = "2"
/10 = "3"
/11 = "4"
/12 = "5"
/13 = "6"
/14 = "2"
/15 = "4"
/16 = "4"
/17 = "5"
/18 = "6"
/19 = "7"
/20 = "8"
</item>


<data>
/ columns=[subject, blockcode, trialcode, trialnum, latency, response, stimulusitem, stimulusnumber, stimulusitem, stimulusnumber, list.distancetag, list.ratiotag]
</data>


By Dave - 8/28/2013

For each trial, I want Inquisit to record the difference between the numbers in the pair and
their ratio on the data sheet in addition to the stimulus number (for example, if the stimulus
is “6       9”, the distance would be 3 and
the ratio would be 1.5).


Since both are simple mathematical operations, you could use two <expressions> to compute difference and ratio and log the results to the data file as detailed in the documentation for the <data> element / its /columns attribute.


For your current solution to work, you would (1) have to properly "link" the lists containing the results to the stimuli (see the "How to present stimulus pairs" topic in the documentation) and (2) log the respective list item to the data file via a suitable property (list.listname is not a property and hence returns nothing).