Number Of Items Keyword
N parameter alternative.
More accurately this should be referred to as the Number Of Responses, however historicity being what it is it will remain as is, largely because in DMDX the keyword is nearly redundant. If this parameter is included then the number of responses gathered (not including instructions) is counted and if at the end of the item file the number is not the same as this parameter's value then the infamous ITEM COUNT NOT ZERO message is issued. If this parameter is not specified (in DMDX) then no counting is done and no error messages are issued, unlike previous versions of Dmastr (DM and DMTG) where the N parameter had to be specified and specified correctly in order to avoid the error message.
The whole purpose of the original N parameter was a double check to make sure the item file was gathering the data the experimenter intended to gather, however as time went by both Ken and I have seen item files that are syntactically correct, even functionally correct, nay, they even gathered the intended data, but there was no way get N specified correctly. A mystery, solved only by the removal of N's necessity.