Scrum PSK-I - Professional Scrum with Kanban (PSK 1) Exam

Little's Lawestablishes a relationship between three flow metrics:Work in Progress (WIP),Cycle Time, andThroughput. It provides insights into how changes in one metric affect the others in a stable system​​.

Little's Law is used to understand and manage flow within a system but isnot a forecasting tool for output or future performance. It assumes a stable and predictable system where the input and output rates are consistent.

Why Not True?

Forecasting requires variability, historical data, and often different statistical models. While Little's Law supports system predictability and capacity planning, it does not directly project future Scrum Team outputs or delivery dates​.

Thus, Little's Law helps teams analyze and optimize flow but is not used for forecasting.

Kanban is:

•A strategy for optimizing the flow of value through a process (Option B): Kanban focuses on improving flow and efficiency by using a visual pull system with limited WIP. This strategy helps teams balance demand against throughput and enhance productivity by limiting the number of work items in progress.

Options A (methodology for visualizing workflow) and C (set of practices additive to Scrum) are partially correct but do not fully capture Kanban's purpose. Kanban is not just a visualization tool (A), and while it can be additive to Scrum (C), it is fundamentally a flow-based strategy

Leading indicators are the most appropriate metrics for Daily Scrum because they provide information about the current state of the work and potential future issues. By tracking leading indicators, the team can identify potential problems early on and take proactive measures to address them.

Here are some examples of leading indicators that can be useful during Daily Scrum:

WIP Limits:Are the WIP limits being adhered to?

Blocked Tasks:Are there any tasks that are blocked or waiting for dependencies?

Task Progress:How much progress has been made on each task?

Team Mood:Is the team morale high or low?

By discussing these leading indicators during the Daily Scrum, the team can identify any impediments and take immediate action to keep the work flowing smoothly.

Lagging indicators, on the other hand, provide information about past performance and are not as useful for identifying and addressing current issues. Examples of lagging indicators include cycle time, lead time, and throughput. While these metrics are important for long-term analysis and improvement, they are not as actionable in the context of the Daily Scrum.

Supplementing Scrum with Kanban practices encourages team collaboration and swarming. Kanban practices such as visualizing the workflow, limiting WIP, and focusing on flow metrics foster an environment where team members are more likely to collaborate closely to resolve bottlenecks and ensure a steady flow of work. This collaboration, often called "swarming," involves team members working together on fewer items to complete them faster, thereby enhancing team dynamics and efficiency

A Service Level Expectation (SLE) in Kanban provides an agreement or expectation regarding the time it will take to complete a work item. An SLE consists of two main elements:

1.A probability (Option B): This is the likelihood or confidence level (e.g., 85%) that a work item will be completed within the specified period.

2.A period of elapsed days (Option D): This defines the maximum amount of time (e.g., 10 days) expected for a work item to be completed. The combination of these two elements helps set clear expectations and guide planning and forecasting efforts(

Options A (A cost of delay) and C (A forecasted date) are not part of the standard elements defining an SLE. The cost of delay is a concept related to prioritization, and a forecasted date is usually derived from the SLE but is not part of it.

Within the same Kanban system, Work in Progress (WIP) is not a leading indicator for "Story points delivered." While WIP can influence throughput and cycle time, it does not directly correlate with story points delivered, as story points are a measure of effort or complexity rather than flow. The number of story points delivered is not directly influenced by the current WIP levels

The Service Level Expectation (SLE) provides the most benefit during the Daily Scrum. This is because the Daily Scrum is focused on inspecting the progress towards the Sprint Goal and adapting the plan to optimize the flow of work for the day. The SLE helps the Scrum Team understand if work items are on track to be completed within the expected time frames. If the actual cycle times are exceeding the SLE, the team can discuss and make adjustments during the Daily Scrum to address any impediments or to rebalance work, thereby maintaining a steady flow.

By using the SLE in the Daily Scrum, the team gets a daily, empirical measure of their workflow, allowing them to make quick decisions to keep work moving smoothly and predictably. This aligns well with the goal of the Daily Scrum, which is to ensure that the team is on track to achieve the Sprint Goal by the end of the Sprint(

The Definition of Workflow should include policies that dictate how work flows through the system, such as Visualization policies, Pull policies, WIP Limits, Service Level Expectations, Work Item types, and the Definition of Done. These elements help the Scrum Team maintain transparency and consistency in their process, enhancing predictability and facilitating continuous improvement. References: The Kanban Guide for Scrum Teams​​.

During a flow-based Daily Scrum, the team is likely to review metrics such as Work Item Age and Work in Progress (WIP):

•Work Item Age: Helps to identify items that have been in progress for a longer time than expected, signaling possible impediments or the need for swarming to complete those items.

•Work in Progress (WIP): Indicates the number of items currently being worked on, ensuring that the team is not exceeding the agreed WIP limits, which is crucial for maintaining a steady flow

The four key flow metrics in Scrum with Kanban are:

•Work in Progress (WIP): The number of items that are currently being worked on.

•Work Item Age: The time that has elapsed since an item started, which helps identify aging work that may need attention.

•Throughput: The number of items completed over a specific period, helping to measure productivity.

•Cycle Time: The total time from when an item starts until it is finished, used to assess how quickly items are moving through the process.

These metrics are essential for understanding and optimizing the flow of work in a Scrum team using Kanban practices