Question

Why do you think it is important for an engineer to measure variability? Give examples un your engineering specialty.

Answer 1

It is important for an engineer to measure variability because in any measurement in addition to accuracy of the measured value the precision of the measurement values is equally indispensable.

For example consider Quality Control checking of a particular characteristic of a regular production process, such as thickness of O ring. As part of the Quality Control process, a sample containing a specified number of O rings as per the Sampling Plan are drawn and the thickness values are measured.

There are two types of variability: inherent natural variability of the characteristic which can vary from item to item purely by chance due to the statistical nature of the process.

The other type of variability is due to assignable cause, which is to be eliminated.

The objective of the Quality Control process itself is to avoid any assignable causes in the production process.

Thus, we prove that in our engineering specialty, it is important for an engineer to measure variability.