Millisecond Forums

omit trials with latency > 10000 ms

https://forums.millisecond.com/Topic5332.aspx

By Sonja - 1/20/2011

Dear all,


I have a question regarding latencies that exceed 10000 ms. As far as I understand, my script omits latencies bigger than 10000 ms for the computation of D measures:


/ ontrialend = [if(block.iat2compatibletest1.latency  <= 10000 && block.iat2compatibletest1.currenttrialnumber != 1 ) values.sum1a =  values.sum1a + block.iat2compatibletest1.latency]
/ ontrialend = [if(block.iat2compatibletest1.latency  <= 10000 && block.iat2compatibletest1.currenttrialnumber != 1 ) values.n1a =  values.n1a + 1]
/ ontrialend = [if(block.iat2compatibletest1.latency  <= 10000 && block.iat2compatibletest1.currenttrialnumber != 1 ) values.ss1a =  values.ss1a + (block.iat2compatibletest1.latency * block.iat2compatibletest1.latency)]


Now, I have a case where the first totalmaxlatency in the first row (first recorded trial in first recorded block) says 11298 ms while the first latency is 1729 ms. My first guess was that Inquisit omits the 11298 ms in the output data BUT there is no trial missing. There are 24 recorded trials in this block (incompatibletest1) but none of them has the 11298 ms as recorded latency. How can this be?


Furthermore, I understood totalmaxlatency as "The longest response latency for the specified element over the entire
experiment" (manual) but it seems the shown latency in this column is reset every time a new block is recorded. Did I understand something wrong?



Can anyone help on this issue? Thank you so much!



Regards, Sonja


By Sonja - 1/20/2011

I would also like to add the block definition:


<block iat2compatibletest1>
/ bgstim = (iat2targetAleft, iat2orleft, iat2attributeAleftmixed, iat2targetBright, iat2orright, iat2attributeBrightmixed)
/ trials = [1=iat2instructions;3,5,7,9,11,13,15,17,19,21,23,25= noreplace(iat2targetAleft, iat2targetBright);2,4,6,8,10,12,14,16,18,20,22,24= noreplace(iat2attributeA, iat2attributeB)]
/ errormessage = false
/ responsemode = correct
/ ontrialend = [if(block.iat2compatibletest1.latency  <= 10000 && block.iat2compatibletest1.currenttrialnumber != 1 ) values.sum1a =  values.sum1a + block.iat2compatibletest1.latency]
/ ontrialend = [if(block.iat2compatibletest1.latency  <= 10000 && block.iat2compatibletest1.currenttrialnumber != 1 ) values.n1a =  values.n1a + 1]
/ ontrialend = [if(block.iat2compatibletest1.latency  <= 10000 && block.iat2compatibletest1.currenttrialnumber != 1 ) values.ss1a =  values.ss1a + (block.iat2compatibletest1.latency * block.iat2compatibletest1.latency)]
</block>


Is the long totalmaxlatency maybe the latency of reading the iat2instructions? I am not sure whether these are recorded, too.

By Dave - 1/20/2011

(1) The data for IAT-trials with latency > 10000ms will *not* be omitted from the data file. However, these data are not be included in computing D.


(2) The totalmaxlatency property will also include the latency for e.g. trial.iat2instructions.


(3) To see whether the raw data for instruction trials should be recorded in the data file, check the trials' /recorddata settings.


(4) You might want to post the data file in case of further questions.


~Dave

By Sonja - 1/20/2011

Thanks Dave, this helped a lot! No further questions for the time being.