Although variability is high because of the significant
increase in scores from the beginning of the intervention phase to the end, the trend is quite
positive and reflects the incremental nature of the intervention phase instruction. The score for
probe 10 (the 7th intervention session out of 8) altered the linear pattern slightly, but then the
probe 11 score of 100% correct brought the line back to its positive trend. Taken together, the
variability and trend characteristics show that the data for Jeff's intervention phase has a high
degree of stability.