Yellow Belt Chapter 5: Basic Six Sigma Concepts

Question 1

Standard Deviation

Answer 1

6S is about decreasing defects.

-Decreasing defects that you need to decrease the variance of defects. Variance= S^2

A large SD means huge differences from the mean (x) and a small SD means a small difference from the mean.

Question 2

The Pareto Principle

Answer 2

• 80/20 Rule applies:
• 20% of causes are the result of 80% of effects/ problems leading to defects

a Fishbone Diagram:
- Fisbone diagram with problem can be created to look at a problem/ process with spine of fish as possible causes. (20% fo those causes will be 80% of effect to problem)

Question 3

Creating a Basic Pareto Chart in Excel

Answer 3

*** Pareto Charts are very similar to Fishbone Diagram

1. ) Create a column for data labels
2. ) create a bar chart
3. ) Add a trendline w/ percentages
4. ) Use the 80% to take the first 2 reasons as 80/20 rule

Question 4

Voice of the Customer

Answer 4

VOC is an important idea in 6S. You must understand complaints of the customer to create a good product:

• increase consistency of a product
• increase quality of a product to a customer

***You understand VOC by seeking feedback from your customer

Question 5

Building a VOC Campaign

Answer 5

Ways to build VOC:

• survey through telephone
• focus groups in person/online
• interviews
• beta or user testing
• feedback forums
• customer complaints
• social media/site interaction
• reviews
• forums

Question 6

Selecting the Right VOC Tools

Answer 6

So above, I have mentioned many VOC tools.

• You need to see which VOC tool is the right one.
• The way you do that is by determining differences in costs vs. benefits vs. disadvantages.

***costs, benefits, disadvantages

Question 7

The Likert Scale

Answer 7

How will you measure the VOC data? Will you create a statistic and create charts to determine meaning to the data?

Or will you use a Likert Scale?
(strongly agree–> strongly disagree)

Question 8

Basic Metrics

Answer 8

Basic Metrics of 6S include:

-Sigma Level=
( Opp- defects/ opp *100)

-DPMO
(Defects per million opportunities)

(defects/ number of opp.) * (1 million) =
3.4 DPMO

-DPU=
(Defects/number of opportunities)
-FTY
-RTY

Question 9

Defects per Million Opportunities

Answer 9

DPMO=

defects/ opportunities * 1,000,000

Question 10

Defects per Unit

Answer 10

DPU= defects/ opportunities

Question 11

First Time Yield (FTY)

Answer 11

FTY=

number of good products produced/ total products produced

Question 12

Rolled Throughput Yield (RTY)

Answer 12

Rolled Throughput Yield provides a probability that a unit will be generated by a process w/ no defects.

number of products enetering - number of rework/ number of products entering process