Variation: Common Cause vs. Special Cause
Most discussions about performance focus on averages. While averages give us clues to targets and expectations, understanding variation is extremely important to driving lasting change. There are two types of variation, common cause and special cause. Common cause variation is innate in all systems, it is sometimes referred to as “noise.” For example, it takes me 28 – 35 minutes to drive to work. Each day is different from the last due to a number of factors associated w