CPIM Practice Exam

What type of variation is considered a random fluctuation in data?

1. Control variation

2. Random variation

3. Assignable variation

4. Systematic variation

The correct answer is: Random variation

Random variation refers to the inherent fluctuations that occur in any measured data, which are generally caused by unpredictable factors. These can arise from a variety of sources, such as variations in the environment, measurement errors, or natural inconsistencies in the process. This type of variation is expected and can be modeled statistically by using probability distributions, which helps in understanding the degree of uncertainty in the data. Control variation, on the other hand, pertains to the processes being monitored and can involve systematic measurement or adjustments that are made to keep processes within expected limits. Assignable variation, in contrast, relates to variations that can be traced to specific causes, which means that they are not random and can often be corrected or eliminated. Systematic variation is consistent and predictable, often due to specific factors or changes that can be identified and accounted for. Random variation is significant in quality control and process management as it sets the groundwork for understanding how much of the observed variability is expected due to random chance, versus variability that can be attributed to identifiable causes.