Millisecond Forums

That has worked perfectly - thank you kindly for such a quick reply and such detailed instructions.

#1: Create a bunch of new <values> entries to hold the respective statistics. E.g.

<values>
/ n1hits = 0
/ n2hits = 0
...
</values>

(same for false alarms, etc.)

#2: Aggregate those statistics according to n-level at the end of the <block>, e.g.

<block s_ntask>
/ onblockbegin = [
                        values.currenttarget = 0; values.minus1 = 0; values.minus2 = 0; values.minus3 = 0; values.minus4 = 0;
                        values.Hits = 0; values.FalseA = 0; values.Misses = 0; values.CorrReject = 0;
                        values.TotalBlocks += 1;
                        values.starttrialcounter = 0;
                        values.repetitioncounter += 1;
                        ]
/ onblockend = [if (values.n==1) {values.n1hits+=values.Hits; }; ]
/ onblockend = [if (values.n==2) {values.n2hits+=values.Hits; }; ]
/ trials = [1 = expinstructiontrial; 2 = start; 3 - 22 = noreplace(nontarget, nontarget, nontarget, nontarget, nontarget, nontarget, nontarget,
                                                                                target, target, target)]
...      
</block>

(same for false alarms, etc.)

#3: Add the newly created values to the summary data output:

<summarydata >
/file = "SingleTaskNback_summary.iqdat"
/columns = [script.startdate, script.starttime, script.subjectid, script.groupid, script.elapsedtime, values.completed,
values.TotalHits, values.TotalFA, values.DV, values.n1hits, values.n2hits, ... ]
</summarydata>

(same for false alarms, etc.)