Nielsen executives said most participants simply filled out the diary at the end of the week by recall.
The Nielsen executive declined to comment on the new competition, except to say, "We think our system is a better one."
Nielsen executives have said they have examined their system and found no flaws.
But Nielsen executives argued that the system will not be an invasion of privacy.
Nielsen executives have said the new system provides a more accurate picture of what people are watching.
A Nielsen executive said the skipping over of such homes was rare.
The drop has been described, by both network and Nielsen executives, as unlike anything they had previously encountered.
But Nielsen executives do not agree that last year's ratings were wrong.
After last year's report of declining viewership, Nielsen executives suggested larger cultural reasons for the trend.
But Nielsen executives say they had no choice.