The Six Sigma philosophy believes in statistical facts. There is no room for error and therefore there is no room for guessing or judgement. Therefore the few inputs that were guessed for being the critical ones in the earlier stages of define and measure now need to be confirmed with statistical analysis.
The purpose of the analyze module is two phased:
To confirm the impact that the critical inputs have on the output which is critical to quality
To ensure that the critical inputs are recorded at an actionable level i.e. there is enough information available about these inputs to take action at a later stage
Approach Used in the Analyze Phase
Before the introduction of Six Sigma into business, the common practise was to have a business problem and then quickly start working towards a business solution. However in Six Sigma the approach is process focussed and data driven.
The approach is to first convert the business problem into a statistical problem. The data collected in the measure phase is then used to solve this statistical problem and come to a statistical conclusion. This statistical conclusion guides the appropriate plan of action which is then put into effect in a very controlled manner.
Inputs to the Analyze Phase
The analyze phase receives inputs in the form of identification of the possible few critical inputs to the process being improved. For instance if a cars servicing service process is being improved, the critical inputs that may make it to the analyze stage could be the technical expertise of the workers, the place of service, the time required for service and so on. This information acts as the raw data. However, it is not only this list that must come as the input. Six Sigma professionals can do little more than look at such lists. For each input that has been classified as critical, the measurements collected by running the process must also be available. This will enable the Six Sigma team to statistically prove the inputs which are critical.
Outputs from the Analyze Phase
The following are the outputs from the Analyze phase:
A list of the confirmed critical inputs with their statistical proofs
A list of the rejected critical inputs with their statistical proofs
It is this thorough methodical approach that is used by Six Sigma in finding out issues that makes it more successful than any other quality tool. Reliance on facts is the main feature of Analyze phase as well as of the Six Sigma methodology.