Q1. What is the Pareto Principle?
The Pareto principle (or the 80/20 Rule) states that, for many events, roughly 80% of the effects come from 20% of the causes. For example:
- 20% of the input = 80% of the result
- 20% of the workers’ efforts deliver = 80% of the result
- 20% of the customers results in = 80% of the revenue
- 20% of the bugs cause = 80% of the crashes
- 20% of the features cause = 80% of the usage
The Pareto principle (it’s just an observation and not law) says that one must realize focusing upon the overall efforts contributed by the 20%s instead of wasting must time on 80%.
Q2. Name some of the Quality Management tools in Six Sigma.
There are several quality management tools. Some of them are:
- Cost-benefit analysis
- CTQ Tree
- SIPOC analysis
- COPIS analysis
- Taguchi methods
- 5s
- Seven wastes
- Value stream mapping:
- Visual workplace
- Quality function deployment (QFD)
Q3. Name the different kinds of variations used in Six Sigma?
The different kinds of variation are —
- Mean
- Median
- Range
- Mode
Q4. What is the difference between the Six Sigma DMAIC and DMADV methodologies?
The DMAIC methodology, instead of the DMADV methodology, should be used when a product or process is in existence at your company but is not meeting customer specifications or is not performing adequately.
The DMADV methodology, instead of the DMAIC methodology, should be used when:
- A product or process is not in existence at your company, and one needs to be developed.
- The existing product or process exists and has been optimized (using either DMAIC or not) and still does not meet the level of customer specification or Six Sigma level.
Q5. Can you explain the standard deviation?
Standard deviation indicates the degree of variation in a set of measurements or a process by measuring the average spread of data around the mean.
Q6. What is the difference between defect and defective?
A defect is any non-conformance of the unit of the product with the specified requirements. A defective is a unit of work that contains one or more flaws.
Q7. Explain FMEA
FMEA is a qualitative and systematic tool, usually created within a spreadsheet, to help practitioners anticipate what might go wrong with a product or process.
Q8. What is Lean Six Sigma?
Lean Six Sigma is a performance improvement methodology that involves removing stuff that does not add value to the process and reducing variation. This philosophy relies on a collaborative team effort. Lean Six Sigma contributes to high quality and customer satisfaction.
Q9. What are the tools of Lean Six Sigma?
Various tools used in Lean Six Sigma include –
- FMEA
- Kaizen (continuous improvement)
- Pareto Chart
- Poka-yoke (mistake-proofing or inadvertent error prevention)
- Value Stream Mapping
10. What is the main difference between Lean and Six Sigma?
Ans. Six Sigma follows the DMAIC methodology to reduce waste. On the other hand, Lean uses these following 7 steps:
- Overproduction: This occurs when products are being produced but there is no customer to demand it.
- Waiting: If there is a time lag after every step of production, no value is being to the project in the meantime.
- Transport: This happens when products are being moved in an inefficient way.
- Motion: This one denotes poor work standards and employees being involved in inefficient activities between tasks.
- Over-processing: This takes place when you spend too much time producing a product.
- Inventory: When your inventory level is too high and you have too much work in progress, this kind of waste takes place.
- Defects: This is the number of times when employees spend identifying and fixing production mistakes.
Q11. What is a good Six Sigma score?
From a quality perspective, Six Sigma is defined as 3.4 defects per million opportunities. If the company is able to achieve this then it is considered to be a good score.
Q12. What are the 5 steps of the Six Sigma improvement model?
Six Sigma consists of five basic phases: Define, Measure, Analyze, Improve, and Control. This process is also known as DMAIC.
Q13. What is 6s in Six Sigma?
6S is a modification of the 5S methodology which includes “Safety” as the 6th term.
Q14. Who Forms The Part Of Six Sigma Implementation Team?
Six Sigma implementation team has five key players:
Executive leaders
Champions
Master black belt
Black belts
Green belts
Q15. When and By Whom Was Six Sigma Developed?
In 1986 Six Sigma was developed by Motorola.