1. http://www.qmss.biz Capability Analysis 1 Skewed Distributions median mean median mean Hours of sleep per week – Skewed leftTime to drive to work – Skewed right Average class shoe size – No skew mean = median

2. http://www.qmss.biz Capability Analysis 2 Standard Deviation Standard Deviation (σ) = the average difference of each value from the mean Σ(x - ) 2 n -1 Std dev = It is a measure of how spread apart each individual data point is from the mean

3. http://www.qmss.biz Capability Analysis 3 What is Cp? C p is a measure of how well the variation in the data can fit within the tolerance limits If the variation (6σ) is less than the tolerance limits, you have acceptable variation If the variation (6σ) is greater than the tolerance limits, you have unacceptable variation LL UL 6σ6σ6σ6σ

4. http://www.qmss.biz Capability Analysis 4 Examples +1+2+3-3-20 USL C pk = 0.33 15.87% Predicted failure rate