System Analysis | Research & Encyclopedia Articles

System analysis is a broad, technical area focused on the creation, enhancement, and trouble-shooting of systems for users. These can be data, information, or knowledge systems. The purpose of these systems is to provide an understanding of what is going on in a particular environment. Sensors, including radar, sonar, and satellites, for example, are components of systems that provide specific knowledge about the physical world. Sensors in the home can warn residents that someone is breaking in. Telephones are part of a system that brings police assistance when one dials 911. People have computers they use to perform a number of tasks—from writing term papers or diaries to communicating with people they have never met via "messaging" software programs. There are decision support systems that help people use computers to solve problems, and communication systems that tell people what is happening around them. System analysis is used to design, enhance, and fix problems in all of these systems.

System analysis is creative work. The systems analyst can be considered an artist, an information scientist, and an engineer, all in one. The work begins with thinking about how to accomplish something. System analysis can be considered to have three primary functions, each of which is related to the others. First, system analysis is done to fix something that has gone wrong and to help one understand why there is a problem. Second, analysis is used to figure out how to do something more easily and less expensively as new technologies become available. Third, system analysis is done to help design a system that can accommodate future circumstances, such as anticipated events that are not being experienced now, but that might need to be dealt with in the future.

Each system has components that perform certain functions and, when put together, do a particular job, or serve a specific purpose. System analysts are trained to ensure that each component or function of a system—whether people, tools (technology), or procedures— is acting properly. If a system fails, the system analyst tries to find out how and why. The systems analyst then communicates with the designer about the factors found to be related to the failures in order to find a solution and avoid future problems. One way to consider system analysis is that it is a process that first identifies the factors that influence and lead to system breakdown, and then identifies ways to repair or avoid breakdowns.

Systems have a life cycle. They become operational, they age, and they become obsolete. Typewriters have given way to computers. People still use telephone booths but cell phones are replacing them because they allow people to make phone calls and do many other things better and faster. As new tools and technologies become available, people want to use them. The system analyst examines and studies how technology and people can be placed and used in current systems, and figures out how existing systems could benefit from all the new ideas and inventions that are coming to market. System analysis is a process for updating or retrofitting systems, replacing old technology with new, and installing new ways of doing things.

System analysis also considers situations or events where no existing system may yet be available to deal with them, such as biological warfare, or global warming, and analysts work to find ways to better address other large-scale events that affect the fabric of human life. Systems do exist that can respond to events such as hurricanes, tornadoes, floods, and health epidemics. Yet the need to anticipate unpredictable global circumstances—economic, political, medical, or environmental—demands new, creative approaches to minimize the potential damage to lives and property. System analysis is a way to explore how new situations or challenges can be met.

A system analyst investigates; a system design specifies. The analyst asks questions such as who, what, when, where, why, and how. The system designer finds the best procedures, tools, and human skills to meet the needs and requirements of people and organizations. System analysis and system design work best when analyst and designer work together. The analysis component helps reduce the likelihood that design and technology will drive and influence the problem-solving process. If design precedes and directs analysis, there is a good chance that a given system may not be what the user needs or requires. Basements are full of technologically interesting gadgets that people buy and rarely use because they never needed them in the first place—no matter how intriguing the design, they were not designed specifically to meet the identified needs or requirements of the user!

People are born with needs and requirements. A need is a state of being. Requirements are the things that meet these needs. People are hungry orthirsty; they need to feel well; they need shelter from environmental conditions and circumstances. They need to make a living; they need to feel as if their actions have some meaning. To address these varied needs, they require food, water, air, shelter, and other resources. But the resources, or requirements, applied to address these needs in a tropical environment, for example, would be inappropriate in an arctic climate. Individual human characteristics such as personality or physical limitations can also influence the appropriateness of certain resources being applied to meet these needs. Requirements to meet needs vary from situation to situation. The same logic applies to system analysts. They must learn how to match up needs and requirements so that a system will actually function effectively in its particular environment.

Human needs may be physical, psychological, intellectual, emotional, or social. They can generally be identified only through a careful process of examination and investigation. Needs and requirements can be difficult to sort out and obtain from users because dictionaries and people's language habits lead them to ignore the distinctions. But the success of any system depends on the skills of a system analyst to recognize these distinctions and gather the correct needs and requirements information before trying to engineer a system.

The system development cycle consists of the steps taken for the conceptualization and engineering of a system. There are several ways to represent or describe the system development cycle. One is to show the analysis process in a series of blocks in hierarchical (top-down) or horizontal line (timeline) form. Another way is to show the system analysis process as a circle of operations, namely, requirement analysis, specifications, design, implementation, testing, and maintenance. Another approach is to regard the process as representing a waterfall cycle—one step flowing into another in a continuous stream. All share a common property of sequencing. System analysis is a step-by-step procedure: each step follows or interacts with the others, and all are directed toward meeting the objectives stated by the intended user of the system.

Once the initial information gathering stage is completed—that is, user needs and requirements have been identified, and the parties involved in a system design process have agreed on certain parameters of time, money investment, and expected outcomes—the system analyst begins conceptualizing the problems to be solved and the possible solutions to be applied.

One of the first steps is known as event analysis. The system analyst will engage in a detective-like process of investigating the properties and attributes of an event, or of a series of events that make up the problem to be solved. For each event, the system analyst creates a model, which is a tool in the analytical process. A model provides a view, a mental and physical picture, of the total system, explaining how the various parts of the system are structured and how they work together.

A prevailing model for system analysis is to consider three functions: namely, input, throughput, and output. What goes into the system? What happens to it? What is the outcome? These three dimensions of the analysis are applied to each component or event within the system and to the total system, as well, in its final configuration.

Input refers to the data that are acquired, through human or machine means, as part of an event in which the system is engaged. At the throughput stage, these data are transmitted to a processor, which can again be human, machine, or both. The data may then be modified, organized, stored for retrieval, or used in problem-solving and decision-making activities; whatever happens to it during processing is part of the throughput function. The output of a system, or of an event within the system, is the result of the processing steps being applied to the data originally entered into the system. The system analyst's model should account for everything that happens from the time data enters the system to the point at which the end results are achieved.

Throughout the system analysis process, analysts test the ideas and conclusions that arise. Often the model of the system provides the basis for creating a prototype of what is being studied. Although prototyping is a common exercise of designers, who use prototypes to test system configurations and hardware-software specifications, it is also a method for the system analyst to refine the conclusions of the analysis before design decisions are made.

Documentation is a necessary part of system analysis. Documentation means that all actions taken in the process of analyzing a system are recorded. This provides an enduring record of everything that has taken place and all the thoughts or ideas generated throughout the process. This includes both the individual work and testing done by a particular system analyst, and the group work, such as brain-storming, that is usually part of the overall process of analyzing and designing a system. Documentation objectifies the system analysis process. Thorough documentation can help reduce the amount of guessing that goes into solving certain system problems. It helps analysts keep track of what has been tried, and when, and under what specific circumstances. It can be useful in future work on a particular system, and it is a practice through which the process and outcomes of system analysis can be improved and validated.

Decision Support Systems; Design Tools; Information Systems; Office Automation Systems; Systems Design.

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