Managing It chapter9

1. What is a control chart? When is a process said to be in statistical control? How would you know if it was not?

A control chart provides a picture of how a particular process is behaving over time. All control charts have a centerline and control limits on either side of the centerline. The centerline represents the observed average, while the control limits on either side provide a measure of variability. In general, control limits are set at ±3_ (i.e., ±3 sigma) or ±3s, where _ represents the population standard deviation and s represents the sample standard deviation. If a process is normally distributed, control limits based on three standard deviations provides .001 probability limits. Variation attributed to common causes is considered normal variation and exists as a result of normal interactions among the various components of the process—i.e., chance causes. These components include people, machines, material, environment, and methods. As a result, common cause variation will remain stable and exhibit a consistent pattern over time. This type of variation will be random and vary within predictable bounds. If all observations fall within the control limits and the variation pattern is random, the process is said to be in statistical control. When one of the following conditions is observed, the process may be exhibiting nonrandom behavior and be out of statistical control: · A single point falls outside of the 3 control limit · At least two of three successive values fall on the same side of and more than two standard deviations from the centerline. · At least four out of five successive values fall on the same side of and more than one standard deviation away from the centerline. · At least eight successive values that fall on the same side of the centerline.

1. What is a defect? Give an example of a software defect.

A defect is an undesirable behavior associated with the product or process (Ginac 1998). It is a failure to comply with a requirement (Lewis 2000). In software development, defects are often referred to as bugs.1

1. What is a process metric? Give an example.

A process metric is a measurement of the defects introduced by the processes required to develop or create the product deliverables. Example would include such metrics as a defect arrival rate, defects by phase, defect backlog, fix response time, and defective fixes.

1. Why did the teachings of Deming and Japan have such an important impact on Japan just after World War II?

As Japan was attempting to rebuild after WWII, they faced a problem of having a reputation for inferior products. Having few natural resources, they were dependent on exporting manufactured goods. If their export programs were to be successful they needed to change both the fact and perception of producing low quality products. The success they enjoyed as a result of embracing quality improvement methodologies made the work of Deming and Juran central to their industrial culture.

1. Define quality in your own words. How would you define quality in a word processing, spreadsheet, or presentation software package?

Attributes such as dependability or safety may be just as important to the customer.

Why should quality management include both the products and processes of a project?

By focusing on both the product and chain of project processes, the project organization can use its resources more efficiently and effectively, minimize errors, and meet or exceed project stakeholder expectations.

1. What is a project metric? Give an example.

Metrics - Quality Metrics: Product, Process, Project

1. What is a product metric? Give an example.

Metrics are vital for gauging quality by establishing tolerance limits and identifying defects. Metrics that attempt to describe the intrinsic quality and characteristics of the project's deliverables and final product are called product metrics. Examples would include mean time to failure, defect density, customer found defects, and customer satisfaction.

What is PQM?

PQM is an abbreviation for Project Quality Management which is defined as: The processes required to ensure that the project will satisfy the needs for which it was undertaken. It includes all activities of the overall management function that determine the quality policy, objectives, and responsibility and implements them by means of quality planning, quality assurance, quality control, and quality improvement, within the quality system.

1. Define the following: (a) Quality planning; (b) quaity assurance; (c) quality control.

Quality Planning 1) Identify who the customers are. 2) Determine the needs of those customers. 3) Translate those needs into our language. 4) Develop a product that can respond to those needs. 5) Optimize the product features so as to meet our needs as well as customer needs. Quality Improvement 6) Develop a process that is able to produce the product. 7) Optimize the process. Quality Control 8) Prove that the process can produce the product under operating conditions. 9) Transfer the process to Operations. § Quality Planning—Determining which quality requirements and/or standards are important for the project and the product and then documenting how compliance will be demonstrated. § Quality Assurance—provides the basis for continuous improvement by auditing and evaluating the results from quality control measurements so that appropriate quality standards and operational definitions are used. § Quality Control—Monitoring and documenting the results of executing project quality activities to eliminate causes unsatisfactory performance and implement new processes and techniques to improve project quality throughout the organization.

Why is the number of features of a product or software system not necessarily the best measure of that system's quality?

Similarly in software development, we can build systems that have a great deal of functionality, but perform poorly. On the other hand, we can develop systems that have few features or limited functionality, but fewer defects.

1. What is process capability?

Software process capability—The expected results that can be achieved by following a particular software process. More specifically, the capability of an organization's software processes provides a way of predicting the outcomes that can be expected if the same software processes are used from one software project to the next.

What is process maturity?

Software process maturity—The extent to which a particular software process is explicitly and consistently defined, managed, measured, controlled, and effectively used throughout the organization.

What is scientific management? Why was it so popular? Why was it so controversial?

Using an approach called scientific management, Taylor believed that a task could be broken down into smaller tasks and studied to identify the best and most efficient way of doing each subtask. In turn, a supervisor could then teach the worker and ensure that the worker did only those actions essential for completing the tasks, in order to remove human variability or errors. At that time, most workers in U. S. factories were immigrants, and language barriers created communication problems among the workers, their supervisors, and even with many coworkers. The use of a stopwatch as a basis for time-motion studies provided a more scientific approach. Workers could produce at their full potential, and arbitrary rates set by management would be removed. To be successful, Taylor also believed that the scientific management approach would require a spirit of cooperation between the workers and management. Although the scientific management approach became quite popular, it was not without controversy. Many so-called efficiency experts ignored the human factors and tended to believe that profits could be increased by speeding up the workers. Dehumanizing the workers led to conflict between labor and management that eventually laid the foundation for labor unions. Just three years before Taylor died, he acknowledged that the motivation of a person can affect output more than just engineered improvements.

1. Describe validation. What activities support validation?

Validation is a product-oriented activity that attempts to determine if the system or project deliverable meets the customer or client's expectations and ensures that the system performs as specified. Validation is supported primarily by testing using one or more of several approaches: Unit, Integration, Systems, and/or Acceptance Testing.

1. Describe verification. What activities support verification?

Verification focuses on the process-related activities of the project to ensure that the product or deliverable meets its specified requirements before final testing of the system begins. Verification requires that the standards and metrics be defined clearly. Moreover, verification activities focus on asking the question of whether we followed the right procedures and processes. Verification is supported by three types of reviews: Technical, Business, and Management.

1. What is an Ishikawa diagram? How can it be used as a quality control tool for projects?

he fishbone, or Ishikawa, diagram developed by Kaoru Ishikawa was developed to analyze the causes of poor quality in manufacturing systems. The diagram can be used for understanding the causes or factors of a particular quality characteristic or problem. A particular quality characteristic or problem is represented by targeted box and then the major causes are identified and linked to the subject of study. Each major cause then is further subdivided into potential sub-causes. This approach is often deployed by using either brainstorming or learning cycle approaches. Once the diagram is completed, the project team can investigate the posited causes and recommend solutions to address the problem.

1. What is a control chart? When is a process said to be in statistical control? How would you know if it was not?

§ A control chart provides a picture of how a particular process is behaving over time. All control charts have a center line and control limits on either side of the center line. The center line represents the observed average, while the control limits on either side provide a measure of variability. § To detector test whether a process is not in a state of statistical control, one can examine the control chart for patterns that suggest nonrandom behavior o A single point falls outside the 3σ control limits.

Describe an immature organization.

§ In an immature software organization, software processes are improvised or developed ad hoc. For example, a software project team may be faced with the task of defining user requirements. When it comes time to complete this task, the various members of the team may have different ideas concerning how to accomplish it. Several of the members may approach the task differently and, subsequently achieve different results. Even if a well-defined process that specifies the steps, tools, resources, and deliverables required is in place, the team may not follow the specified process very closely or at all. § The immature software organization is characterized as being reactive; the project manager and project team spend a great deal of their time reacting to crises or find themselves in perpetual state of fire fighting. Schedules and budgets are usually exceeded. As a result, the quality and functionality of the software system and the associated project deliverables are often compromised. Project success is determined largely by who is (or who is not) part of the project team. In addition, immature software organizations generally do not have a way of judging or predicting quality. Since these organizations operate in a perpetual crisis mode, there never seems to be enough time to address problem issues or improve the current processes.

How does "conformance to requirements" or "fitness for use" provide a definition of quality for a product or information system?

§ In business, quality has been defined in terms of "fitness for use" and "conformance to requirements." § "Fitness for use" concentrates on delivering a system that meets the customer's needs, while "conformance to requirements" centers more on meeting some predefined set of standards. Therefore, quality depends on the needs or expectations of the customer

Describe a mature software organization.

§ Mature software organizations, on the other hand, provide a stark contrast to the immature software organization. § More specifically, software processes and the roles of individuals are defined explicitly and communicated throughout the organization. The software processes are consistent throughout the organization and improved continually based on experimentation or experiences. The quality of each software process is monitored so that the products and processes are predictable across different projects. Budgets and schedules are based on past projects so they are more realistic and the project goals and objectives are more likely to be achieved. § Mature software organizations are proactive and they are able to follow a set of disciplined processes throughout the software project

1. What is a standard? What role do standards play in project quality management?

§ Standards are documented agreements, protocols, or rules that outline the technical specifications or criteria to be used to ensure that products, services, processes, and materials meet their intended purpose. § Standards also provide a basis for measurement because they provide a criterion, or basis, for comparison.

1. Describe how technical, management, and business reviews are different.

§ Technical reviews—A technical review ensures that the IT solution will conform to the specified requirements. This review may include conformance to graphical user interface (GUI) standards, programming and documentation standards, naming conventions, and so forth. § Business reviews—A business review is designed to ensure that the IT solution provides the required functionality specified in the project scope and requirements definition. However, business reviews can include all project deliverables to ensure that each deliverable i. is complete ii. provides the necessary information required for the next phase or process iii. meets predefined standards iv. conforms to the project methodology § Management reviews—A management review basically compares the project's actual progress against the baseline project plan. In general, the project manager is responsible for presenting the project's progress to provide a clear idea of the project's current status. Issues may need to be resolved, resources adjusted, or decisions made either to stay or alter the project's course. In addition, management may review the project to determine if it meets scope, schedule, budget, and quality objectives.