Use interval censoring when you plan to inspect units for failures at preset intervals. You can space these intervals equally in time or in log time, or you can set intervals so that the expected number of failures in each interval is the same. For more information on interval censoring, go to Data censoring.
 Number of inspections for each stress level
 Enter the number of inspections for each stress level, in order from the lowest stress level to the highest stress level. The number of values that you enter must equal the number of test stress levels.
 Inspection Times
 Indicate how to space the inspection times. The number of values that you enter must equal the number of test stress levels.

 Equally spaced: Select to equally space the inspection times. Then enter the time of the last inspection for each stress level, in order from the lowest stress level to the highest stress level.
 Equal probability: Select to make the expected proportion of failures the same in each interval. Then enter the expected percent of failures at each stress level, in order from the lowest stress level to the highest stress level.
 Equally spaced in ln time: Select to equally space the natural log inspection times. Then enter the time of the first inspection for each stress level and the time of the last inspection for each stress level. Enter the times in order from the lowest stress level to the highest stress level.