Lean Six Sigma Green Belt – Six Sigma Analyze Phase
- Introduction to Analyze Phase & Agenda
Welcome to the analyze phase of Lean six Sigma Green belt which is driven using Minitab. Minitab is a statistical tool which is Guid based graphical user interface. It is very easy to navigate and extensively used across the globe in most of the Fortune 500 companies needs and it is used to a very great extent in most of the universities to deliver trainings on statistics and six sigma and so on and so forth. What is analyzed face all about? Even before that, do you remember this equation which says y is equal to function of inputs output? Y is equal to function of inputs.
So my output might be dependent on one input or it might be dependent on multiple inputs. For instance, it might be dependent on x one x two x three, so on and so forth. Now, my key criteria in analyze fees is to list down all these potential inputs. So I’m going to list on all these potential inputs and then I am going to pick up the most critical input which is going to impact my output significantly. In short, I can say that this analyze phase is all about identifying your y, right? Identifying and shortlisting your critical x’s. You’re going to identify and shortlist all the critical inputs which are going to impact your output.
This is your analyze phase all about. So let us look into what are the various topics which we are going to look into as part of analyze phase. Here we go. We are going to look into three steps of analyze fees which is primarily identifying all the inputs. We first identify all the potential inputs and then we are going to shortlist the identified inputs and then we are going to come up with the critical inputs. Finally, as part of step three, we are going to check whether the inputs, critical inputs which we have shortlisted are significant or not. Are they sufficient to meet a project objectives or not? That is what we will do. So identify all inputs.
This is the first step. How would you identify all the inputs? Using various qualitative techniques such as affinity diagram, fishbone diagram, five y analysis and all that. We will also look into process map analysis which is value stream mapping to identify all the critical inputs or all the potential inputs which would then translate to your critical inputs.
We are going to use a failure mode and effect analysis, FME, which is risk based analysis. Using this also we will try to identify all the potential inputs. Then we’ll look into parado chart which is also famously known as 80 20 rule. We then move on to the second step which is shortlisting your critical inputs out of many inputs, out of trivial many inputs, we want to come up with critical few inputs, vital few inputs.
That is what we will do here as part of step two. Using hypothesis testing, right? Using scatter diagram correlation and regression we will be able to identify what those critical inputs are. And finally, as part of step three, we are going to check for sufficiency of critical inputs. And then we will do a quick recap and then we’ll move on. Okay? Now let us look into analyze phase, the three steps. First step is identifying all the inputs which might potentially impact your output. So once again, this equation becomes imperative. You cannot do away with this entire six sigma session is dependent on this. Your entire life, by the way, is dependent on this, right? If a man has to be or if a man is unhappy, there could be n number of reasons, right? One obvious reason is probably he’s married. Yeah. Jerks apart y is equal to f of x is extremely important equation. So analyze phase is all about identifying all your inputs. Out of that, you pick up the critical inputs. Most important inputs. Even when you get married, even before you get married, probably you’ll date with a few of the girls.
Or probably you’ll go and look out for girls to get married. If you’re a man, basically, right? You look out for women to get married. Out of all the women, you pick up one woman who best suits you, right? Or if you want to further rein your life, probably you can look into marrying two or three of them, right? Managing one woman itself is extremely difficult. All right?
No offenses meant just to bring in the humor. That’s it. With all due respect to the women, alright? Second step is shortlist to identify the critical inputs. You try to identify those critical inputs, the most important inputs probably here, you’ll end up identifying 30 to 35 inputs. Out of that, probably you will shortlist ten to 15 inputs and say that all of these many, these are extremely critical in meeting my project objectives, maybe. Yeah. And then we will check whether the inputs which we have shortlisted and which we have termed as critical are sufficient for meeting our project objectives or not. That is what we will do. Let us look into the tools which help us identify all the inputs as part of step one.
- Identify all Inputs
Before identifying all inputs, please remember and bear in mind that identifying inputs would be extremely expensive and extremely time consuming. So you have to be judicial in time, boxing yourself and saying that hey, within a week or so I’ll try to identify all the inputs. Do not spend one year or endless time in identifying all your inputs. So you have to be extremely judicial in doing so. Focus should be to shortlist and narrow down the big list of potential inputs. You might end up with thousands of inputs which might potentially impact your output, right? But you’ll have to be judicial once again in your narrowing down and shortlisting this big list. And third point which you’ll have to remember is take assistance from the cross functional team to shortlist the inputs. Don’t assume that your department or your function knows everything or you as an individual know everything.
Do not assume so, right? You will end up identifying only those inputs which you feel are potentially impacting your output if you are the only person doing that, or if you’re doing this exercise with a team within your function or within your department if you involve cross functional team, probably they will say that, hey, do you know what? These are the bunch of inputs which are out of the scope of your department of function which might also impact your output or project objective. So this is extremely important, right? You will have to involve your cross functional team always. Here are a few of the tools and techniques which we use to identify all the inputs. We have qualitative tools, brainstorming, structured brainstorming, affinity diagram and then fishbone diagram. We will also look into process map analysis, we will look into value added, non value added analysis. We will then look into risk based analysis which is FME failure mode and FX analysis.
And then we have a few of the graphical tools pirator diagram, which is also called as 80 20 rule box plot. We have already discussed about this. The five components will have the minimum value, the first quartile, interquartile range, third quartile and the maximum value box plot also helps you identify the outliers. And then we have histogram which is diagrammatical representation of a laundry list of items which we have. And you do some kind of binning, right, which we have already discussed. And then we have scatter diagram. We are going to discuss about the scatter diagram in detail in this particular analyze phase. All right, let us get into some preliminaries of X’s identifying all the inputs, right? So you have your key process output variable which is nothing but your Y, and we know that it is a function of key process input variables, which is your X. I give something as an input. There is a process which happens. I’m giving three as an input. There’s a process which says square. This number three square is nine and that is my output f of X or Y mean the same.
Y is equal to F of X y or F of X rd SIM is equal to OK. Key process input variable. What are the various sources from which you can identify your critical process input variables and what are few of the terminologies within that? So this diagram here quickly explains us about that. It says that we have controllable inputs, x’s or inputs that can be changed to see the effect of output. Sometimes these are called as knob variables. You can Tweak it and see how it’s going to impact. Your output operator has the ability to make changes within the process set up and this is controllable inputs.
I can control it, I can make the changes as and how required. Yeah, it’s similar to your wife who controls you. Right. All right. The second thing is noise inputs, input variables or XS that impact the output variables but are difficult, impossible, or we choose not to control. Do you have any control on the temperature? Is the temperature zero degrees Celsius or is the temperature 42 degrees Celsius? Do you have any control on that? Can you control it? Can you control the humidity? No.
Can you control the kind of government regulations that come in? No, you cannot do that. These are the noise inputs and then we have the critical inputs X’s that have been statistically shown to have major impact on the variability of the Y. That’s the basic definition. You might have multiple inputs, but what are those inputs which are going to have significant impact on Y? Those are your critical inputs. And then this is another basic terminology which you should be aware of.
Standard operating procedures, a standard procedure for running the process, an input variable, X, having a written procedure documented to assess the opt operator. What are the setup instructions if I want to set up a new machine? What are the new set up instructions if we want to change something, if I want people to work in different shifts, right. What is the shift roster going to look like? These are the few of the key terminologies which you should be aware of.