Question

Describe three types of software process metric that may be collected as part of a process improvement process. Give one example of each type of metric.

Short answer

Product metrics (e.g., Lines of Code), process metrics (e.g., Defect Density), and project metrics (e.g., Schedule Variance) are examples of software process metrics.

Step-by-step solution

Understanding Software Process Metrics

Software process metrics are measurements used to quantify the efficiency and effectiveness of software development processes. These metrics help in understanding and improving the overall process performance.

Explain Product Metrics

Product metrics deal with measurements related to software product attributes such as size, complexity, design or structure. An example of a product metric is Lines of Code (LOC), which measures the size of the software by counting the number of lines in the codebase.

Explain Process Metrics

Process metrics provide insights into the software development process itself, focusing on how the process is performed. An example of a process metric is Defect Density, which is the number of defects found in a software during a particular stage of its development divided by the size of the software.

Explain Project Metrics

Project metrics assess the project characteristics and execution, including time, budget, and quality management. One example is Schedule Variance (SV), which measures the difference between the planned progress and the actual progress of a project.

Key concepts

Product Metrics

Product metrics are crucial for evaluating various aspects of a software product. These metrics help in understanding characteristics like size, complexity, and quality of the software. By analyzing product metrics, developers and project managers can get a clear picture of the current state of the software product and make informed decisions on how to improve or maintain it.

One common product metric is Lines of Code (LOC). This metric counts the number of lines in a software's codebase and provides a basic measurement of the project's size. While LOC is helpful, it is essential to consider it alongside other metrics, as a larger codebase does not always translate into higher complexity or quality.

Other product metrics might include Cyclomatic Complexity, which measures the number of linearly independent paths through the program's source code. This metric helps identify the complexity and maintainability of the code, aiding in spotting potential areas that could lead to bugs.

Process Metrics

Process metrics focus on analyzing, understanding, and improving the software development process rather than the software itself. These metrics are vital for identifying inefficiencies in processes and ensuring optimal workflow.

One widely-used example of a process metric is Defect Density. Defect Density measures the number of defects found within the software during a specific development stage divided by the size of the software, often in terms of LOC or Function Points. By tracking Defect Density, teams can gauge the effectiveness of their testing processes and identify stages that require more attention.

Other process metrics might include Cycle Time, which measures the total time taken from the initiation of the development of a feature until its release. Reducing Cycle Time is often a key goal as it directly impacts time-to-market and responsiveness to user needs.

Project Metrics

Project metrics focus on evaluating the overall progress and performance of a software project. This includes managing resources, time, budget, and quality-related information to ensure a successful project outcome.

Schedule Variance (SV) is a key project metric. It is used to track whether a project is ahead or behind schedule. SV is calculated by subtracting the planned progress from the actual progress: \[ SV = EV - PV \] where EV is Earned Value and PV is Planned Value. A positive SV indicates the project is ahead of schedule, while a negative value suggests delays.

Other important project metrics include Cost Performance Index (CPI) and Return on Investment (ROI), which help determine the financial health and viability of a project.