Lean Six Sigma Green Belt Improve Phase and Solutions Questions and Answers — Questions and Answers
Question 1: After brainstorming several potential solutions to reduce invoicing errors, a project team needs to down-select the best option to implement. They create a grid where they score each solution against criteria such as 'Cost to Implement', 'Time to Implement', and 'Impact on Error Rate'. Which tool are they most likely using?
- Fishbone Diagram
- Process Map
- Solution Selection Matrix (Correct answer)
- Control Chart
Correct answer: Solution Selection Matrix
A Solution Selection Matrix is a tool used in the Improve phase to evaluate multiple potential solutions against a set of weighted criteria. This allows the team to make a data-driven decision on which solution is the most viable and impactful.
Question 2: A project team is implementing a solution to prevent assemblers from installing a computer component backward. They design a new version of the component with an offset pin that only allows it to be inserted in the correct orientation. Which Lean technique does this solution exemplify?
- Kanban
- 5S
- Poka-Yoke (Correct answer)
- SMED
Correct answer: Poka-Yoke
Poka-Yoke is a Japanese term that means 'mistake-proofing' or 'error-proofing'. The redesigned component, which physically prevents incorrect assembly, is a classic example of this technique.
Question 3: A team has developed a new software workflow intended to reduce data entry errors. Before rolling out the change to all 200 employees, they decide to implement it with a small group of 10 users for two weeks to gather data and feedback. What is the PRIMARY purpose of this activity?
- To perform a final root cause analysis.
- To validate the solution and identify potential risks on a small scale. (Correct answer)
- To complete the final step of the project charter.
- To discipline the employees who made the most errors previously.
Correct answer: To validate the solution and identify potential risks on a small scale.
This activity is a pilot test. The primary purpose of a pilot is to test a proposed solution in a controlled, real-world environment on a small scale before full implementation. This helps validate that the solution works as expected and uncovers any unforeseen problems or risks.
Question 4: A Green Belt is leading a short, focused, rapid improvement event with a cross-functional team to rearrange a workspace for better flow and efficiency. The event is expected to last 3-5 days and result in immediate changes. What is this type of event called?
- A project Tollgate review
- A Gage R&R study
- A Kaizen event (Correct answer)
- A stakeholder analysis
Correct answer: A Kaizen event
A Kaizen event (also called a Kaizen blitz or rapid improvement event) is a highly focused, short-term (typically 3-5 days) activity involving a cross-functional team to make significant improvements in a specific area.
Question 5: In a Design of Experiments (DOE), a team is studying the effect of two factors—temperature and pressure—on product yield. They discover that the effect of temperature on yield is different at high pressure than it is at low pressure. What is this phenomenon called?
- An interaction effect (Correct answer)
- A main effect
- A confounding variable
- A replication
Correct answer: An interaction effect
An interaction effect occurs when the effect of one factor on the response variable depends on the level of another factor. In this case, the relationship between temperature and yield changes based on the pressure level, indicating an interaction between the two factors.
Question 6: A team is trying to optimize the baking process for a new cookie to maximize its 'crispiness' score. They believe that baking time (10 min vs. 15 min) and baking temperature (350°F vs. 375°F) are the key factors. They decide to test all possible combinations of these settings. What is this improvement technique called?
- 5S
- Full Factorial Design of Experiments (DOE) (Correct answer)
- Pugh Matrix
- Kaizen Event
Correct answer: Full Factorial Design of Experiments (DOE)
A Full Factorial Design of Experiments (DOE) is a statistical approach where all possible combinations of the levels for all factors are tested. This allows the team to analyze the main effects of each factor and the interaction effects between them.
Lean Six Sigma Green Belt Improve Phase and Solutions Questions and Answers
After brainstorming several potential solutions to reduce invoicing errors, a project team needs to down-select the best option to implement.
They create a grid where they score each solution against criteria such as 'Cost to Implement', 'Time to Implement', and 'Impact on Error Rate'.
Which tool are they most likely using?