Millisecond Forums

The latencies those scores are calculated on are the latencies from the <trial> elements AAT_1 to AAT_8

<trial AAT_1>
...
/ ontrialend = [
  ...;
    if (trial.AAT_1.correct) {
        list.AAT1correctlatencies.insertitem(trial.AAT_1.latency, 1);
...;};
]
...
</trial>

Only correct trials are considered.

> Is there a difference in latency and RT?

No. values.RT captures the same thing:

<trial AAT_1>
...
/ ontrialend = [
...
    values.RT = trial.AAT_1.latency;
    values.correct = trial.AAT_1.correct;
...
]
...
</trial>

So, in summary, calculating the median of RTs for all _correct_ instances of <trial AAT_1>, <trial AAT_2>, etc. and then calculating the difference should give you the same result. Note, though, that the order of terms in the difference calculation varies according to the experimental condition (values.expcondition):

<expressions>
...
/ AAT_Diffscore_Cat1 = if (values.expcondition == 1) list.AAT1correctlatencies.median - list.AAT2correctlatencies.median else
list.AAT2correctlatencies.median - list.AAT1correctlatencies.median
...
</expressions>

median latency of AAT_1 - median latency of AAT_2 in the 1st condition, and
median latency of AAT_2 - median latency of AAT_1 in the 2nd condition.

(Analogously for the other categories / difference scores.)

Hope this helps.

Hej,
thanks for the fast reply!
Don't know why, but it's not the same result calculating the medianRT and the Diff_Score if I put out the mistakes...
I have all RTs and put all incorrect out. I did this in Excel.
Then I calculated the median for each AAT1, AAT2, AAT3 und AAT4 (I have just 4...)
Then I calculated the difference.

I also have the medianlatency.
But these median is not the same as the RTmedian (RT without mistakes).

I don't understand, in which way Inquisit built the medianlatency...

Maybe I did something weird I can't find.

Thanks!!!
Anni

So, maybe you could help me in another way:
I would like know the Diffscore for the medianRT for each AAT1, AAT2, AAT3, AAT4.
So I do:
/ AAT_DiffmedianRT_Cat1 = if ( values.expcondition ==1 ) trial.AAT_1.medianRT - trial.AAT2.medianRT else....
/ AAT_DiffmedianRT_Cat2 = if ( values.expcondition ==1 ) trial.AAT_3.median RT - trial.AAT4.medianRT else...

I have to know how the DiffScore is calculated and I would like to know about the Datas...

But Inquisit message: Expression "trial.AAT_1.medianRT_AAT1 & AAT3" is invalid
Do you have an idea? Would be great!!

Thanks!
Anni

There is no such thing as a ".median RT" property. The property you are (probably) looking for is called .medianlatency as in

/ AAT_DiffmedianRT_Cat1 = if ( values.expcondition ==1 ) trial.AAT_1.medianlatency - trial.AAT2.medianlatency

As for why your calculations in Excel don't match Inquisit's own calculations, I do not know. I would have see the actual data, i.e. one summary data file AND the corresponding raw data file.

Hi,
yes, that's right, I m looking for meidan latency.
But I can't understand, how this is calculated in Inquisit, what Inquisit is doing...
I thougt, Inquisit took the value.RT, then take the RT for each category (AAT1, AAT2, AAT3, AAT4), put out mistakes (RT < 100ms, when the joystick was pulled instead of push, else...) and calculate the median for each AAT_... Then calculate the Difference for the Diff Score.
So, I took the RTs and put them in Excel and tried to calculate this way myself. But its no the same!!

Is Inquisit doing something else?
Or is there another way for put out the mistakes? Not only "wrong way for joystick"? <100ms?

Thank you so much!

> I thougt, Inquisit took the value.RT, then take the RT for each category (AAT1, AAT2, AAT3, AAT4),
> put out mistakes (RT < 100ms, when the joystick was pulled instead of push, else...)
> and calculate the median for each AAT_... Then calculate the Difference for the Diff Score.

That is exactly what Inquisit is supposed to be doing. Again, though, I cannot tell you whether _Inquisit_ is making some mistake or if there is some mistake in the _Excel_ calculations that's responsible for the difference in results. As stated previously, you would have to share some actual data for me to be able to check, i.e. one summary data file and the associated raw data file.