Distributional statistics for VP and TT.

The data revealed extremely different distributions of VP and TT for the 40 infants. All the data were calculated based on questionnaire responses of coders for the 1572 five-min segments. A. More than 90% of segments were judged to have some VP, while only 20% of segments were judged to have some TT. B. Crosstabulation showed that the vast majority of segments (74%) were judged to have Some VP and No TT. Only 1% of segments showed Some TT and No VP. C. The data breakdown in terms of the individual 1–5 ratings provided by coders for each segment showed that there were no segments judged to have TT occurring throughout the segment (a rating of 5), while VP was rated to have occurred throughout 31% of segments. Among the segments judged to have some TT, the vast majority were deemed to have occurred less than half the time (a rating of 2), while ratings suggested more than ¾ of the segments had VP occurring during at least half the time.