CDA Value Stream Management 2 — Questions and Answers
Question 1: Which metric best indicates the efficiency of a value stream by comparing value-added time to total lead time?
- Cycle time ratio
- Flow efficiency (Correct answer)
- Throughput rate
- Work-in-progress limit
Correct answer: Flow efficiency
Flow efficiency is calculated as value-added time divided by total lead time, directly revealing how much time is spent creating value versus waiting.
Question 2: In a value stream map, a 'push' system is characterized by:
- Work pulled only when downstream capacity is available
- Work sent to the next step based on a schedule or forecast regardless of demand (Correct answer)
- Kanban signals triggering upstream production
- Customer orders directly initiating each process step
Correct answer: Work sent to the next step based on a schedule or forecast regardless of demand
A push system moves work to the next stage based on a schedule or upstream completion, often creating queues regardless of whether the downstream step is ready.
Question 3: What does a 'kaizen burst' symbol on a value stream map indicate?
- A bottleneck requiring immediate escalation
- An area targeted for rapid improvement (Correct answer)
- A completed process step with zero defects
- A customer demand spike
Correct answer: An area targeted for rapid improvement
Kaizen bursts are starburst symbols placed on a VSM to highlight specific areas where improvement events or kaizen workshops are planned.
Question 4: Which of the following best describes 'takt time' in value stream management?
- The time required to complete one unit from start to finish
- The available production time divided by customer demand rate (Correct answer)
- The average time a work item spends waiting in a queue
- The maximum throughput rate of the slowest process step
Correct answer: The available production time divided by customer demand rate
Takt time sets the production rhythm by dividing available work time by the number of units customers demand in that period.
Question 5: When mapping a current-state value stream, information flows are typically depicted as:
- Solid arrows pointing left to right
- Lightning bolt arrows for electronic flows and straight arrows for manual flows (Correct answer)
- Dashed lines connecting all process boxes
- Circular loops indicating feedback loops
Correct answer: Lightning bolt arrows for electronic flows and straight arrows for manual flows
VSM convention uses straight arrows for manual information flows and lightning bolt arrows for electronic information flows to distinguish communication types.
Question 6: A value stream that has long cycle times but high throughput most likely suffers from:
- Insufficient customer demand
- Large batch sizes and high work-in-progress (Correct answer)
- Too many pull signals
- Excessive takt time
Correct answer: Large batch sizes and high work-in-progress
Large batches keep total cycle time high while pushing many items through, creating the paradox of high throughput paired with long individual lead times (Little's Law).
Question 7: In the context of DA (Disciplined Agile), value streams are typically organized around:
- Functional departments such as QA, Dev, and Ops
- End-to-end delivery of value to a customer or business outcome (Correct answer)
- Individual product backlogs owned by scrum teams
- Annual budget cycles and project portfolios
Correct answer: End-to-end delivery of value to a customer or business outcome
DA aligns value streams end-to-end around delivering a specific outcome or service to customers, crossing functional silos to optimize whole-system flow.
CDA Value Stream Management 2
Which metric best indicates the efficiency of a value stream by comparing value-added time to total lead time?