Lean Six Sigma Yellow Belt Certification Lean Six Sigma Yellow Belt Measure Phase Tools 1 — Questions and Answers
Question 1: A process capability index (Cpk) is used in the Measure phase to determine which of the following?
- How well a process fits within customer specification limits, accounting for process centering (Correct answer)
- The number of defects produced per million opportunities
- The level of agreement between two different measurement instruments
- The average cycle time required to complete one unit of output
Correct answer: How well a process fits within customer specification limits, accounting for process centering
Cpk measures how centered and capable a process is relative to its specification limits. A Cpk of 1.0 or higher generally indicates the process is capable of meeting customer requirements, making it a key output of the Measure phase.
Question 2: Which Measure phase tool plots individual data points in time order to reveal trends, shifts, or cycles in process performance?
- Scatter diagram
- Run chart (Correct answer)
- Pareto chart
- Affinity diagram
Correct answer: Run chart
A run chart displays data sequentially over time, making it easy to spot non-random patterns such as trends or shifts before adding statistical control limits. It is a foundational tool for understanding process behavior across time.
Question 3: In the Measure phase, what does the width of bars in a histogram primarily communicate?
- The ranking of defect categories from most to least frequent
- The spread and distribution of variation within the process (Correct answer)
- The relationship between two continuous variables
- The sequence of steps from supplier to customer
Correct answer: The spread and distribution of variation within the process
A histogram displays the frequency distribution of data, revealing the shape, center, and spread (variation) of a process. Understanding this distribution helps the team establish a baseline and identify whether the process is normal or skewed.
Question 4: What is the primary purpose of establishing a 'baseline' measurement during the Measure phase?
- To set the final target performance level after improvements
- To document the current process performance before any changes are made (Correct answer)
- To identify which suppliers contribute the most defects
- To calculate the minimum sample size needed for future data collection
Correct answer: To document the current process performance before any changes are made
A baseline captures the current, pre-improvement state of the process using objective data. It is essential because it provides the 'before' benchmark against which the success of improvements in later phases (Improve and Control) will be measured.
Question 5: Which of the following best describes 'continuous data' as used in the Measure phase?
- Data that falls into distinct categories such as pass, fail, or defect type
- Data that can take any value within a range, such as temperature, weight, or cycle time (Correct answer)
- Data that is collected only at fixed intervals, such as once per shift
- Data that counts whole-number occurrences, such as the number of errors per form
Correct answer: Data that can take any value within a range, such as temperature, weight, or cycle time
Continuous data can assume any numeric value within a range and is measured rather than counted. It typically provides more statistical information per data point than discrete (attribute) data, making it preferred for capability and variation analysis.
Question 6: A SIPOC diagram is used early in the Measure phase primarily to accomplish which of the following?
- Track defect counts across multiple process steps over time
- Provide a high-level map of the process showing Suppliers, Inputs, Process steps, Outputs, and Customers (Correct answer)
- Calculate the sigma level of the process using defect and opportunity data
- Rank potential causes of variation by their relative impact on the output
Correct answer: Provide a high-level map of the process showing Suppliers, Inputs, Process steps, Outputs, and Customers
SIPOC gives the team a concise, shared understanding of the entire process scope before diving into detailed data collection. By identifying what comes into the process and what goes out, it ensures the team measures the right inputs and outputs.
Lean Six Sigma Yellow Belt Certification Lean Six Sigma Yellow Belt Measure Phase Tools 1
A process capability index (Cpk) is used in the Measure phase to determine which of the following?