Six Sigma is a well-known management breakthrough. There is a dearth of experts who have defined the process in their own way and have come up with a long list of characteristics. However, according to us this performs a task of confusing people rather than actually giving them insight into the way Six Sigma actually works. The best way to describe six sigma would be to say that it is process focussed and data driven. At the crux that’s what it is, it is the application of statistical methods to ensure quality with consistency. The latter part of the article will explain this better.

The Six Sigma Equation

Y=f(x)

The simple looking equation mentioned above can be described as the crux of the Six sigma philosophy. The component parts of the equation are as follows:

• Y = Outputs also known as Dependant Variables
• X = Inputs also known as independent Variables
• F = Function of

What the equation is actually saying is that the outputs we receive are the function of the inputs that we give to our process. Hence if we were able to control the inputs with precision, the outputs would also be controlled in a precise manner

Data Driven

Here is how a typical Six Sigma project works:

1. A thorough understanding is reached about the required state of affairs for outputs i.e. the Y’s are clearly defined
2. A process map is drawn to understand the process through which X’s (inputs) are transformed into Y’s (outputs)
3. Statistical methods are used to find out which amongst the inputs has the greatest bearing on the desired state of outputs. Inputs are never equally important, some of them are more important than the other and must be controlled in such a manner.
4. A desired state of affairs is decided in terms of the amount of inputs that should be added to get the desired outputs.
5. A process is created to monitor the inputs being added to the production. Simultaneously outputs are measured to check whether they confirm to the norms which have been agreed upon

Hence the entire Six Sigma process is dependent upon the use of precise statistical controls. It uses numbers to define the desired state of outputs, the required inputs and whether the process is working as expected.

Consistency

Along with being process and data driven, the whole Six Sigma philosophy is about being consistent. It is about sustained intensity rather than short bursts of power. Six Sigma focuses on developing the capability to deliver the same results over and over again with zero variance rather than delivering it once. Data is used to find out how the process should function, then numbers are used to keep a track of whether the process is functioning the way it was supposed to.