Web Summary

There are three levels of management corresponding to three kinds of decisions, as reflected in the organization chart, a schematic drawing showing the hierarchy of formal relationships among an organizations' employees. (1) Top managers are concerned with long-range, or strategic, planning and decisions. (2) Middle-level managers, id="70332">/olc/dl/47162/middle_managers.htm</dlpage> make tactical decisions to implement the strategic goals of the organization. (3) Supervisory managers make operational decisions, predictable decisions that can be made by following a well-defined set of routine procedures.

Information has three distinct properties: level of summarization, degree of accuracy, and timeliness. To make the appropriate decisions strategic, tactical, operation the different levels of managers need the right kind of information: structured, semistructured, and unstructured. Structured information is detailed, current, concerned with past events, records a narrow range of facts, and covers an organization's internal activities. Unstructured information is summarized, less current, concerned with future events, records a broad range of facts, and covers activities outside as well as inside an organization. Semistructured information includes some structured information and some unstructured information.

Computer-Based Information Systems. Six types of computer-based information systems provide managers with appropriate information for making decisions: (1) A transaction processing system (TPS) is used by supervisory managers to keep track of transactions recorded events having to do with routine business activities-needed to conduct business. A TPS produces detail reports, which contain specific information about routine activities. (2) A management information system (MIS) is used by middle managers. An MIS uses data from a TPS to produce routine reports—summary reports to show totals and trends, exception reports to show out-of-the-ordinary data, periodic reports produced on a regular schedule, and demand reports to produce information in response to an unscheduled demand. (3) A decision support system (DSS) is also used by middle managers. A DSS provides models mathematical representations of real systems—that gives managers a tool for analysis and helps them focus on the future. (4) An executive support system (ESS) is used by top managers to support strategic decision making. (5) An office automation system (OAS) is used by all levels of managers as well as nonmanagers. An OAS combines various technologies, such as word processing, scheduling software, e-mail, and the like, on a network to reduce the manual labor required in operating an efficient office. (6) An expert system helps users solve problems that would otherwise require the assistance of a human expert.

Systems Development: The Six Phases of Systems Analysis & Design. A powerful tool for helping organizations keep up with new information needs is systems analysis and design. In general, a system is a collection of related components that interact to perform a task in order to accomplish a goal. Participants in an information-system project should be users, managers, and technical staff, including systems analysts, information specialists who perform systems analysis, design, and implementation.

Systems analysis and design is a six-phase problem-solving procedure for examining an information system and improving it. The six phases make up the systems development life cycle (SDLC), the step-by-step process that organizations follow during systems analysis and design. The six steps are preliminary investigation followed by systems analysis, design, development, implementation, and maintenance.

(1) The objective of preliminary investigation is to conduct a preliminary analysis, propose alternative solutions, describe costs and benefits, and submit a preliminary plan with recommendations.

(2) The objective of systems analysis is to gather data, analyze the data, and write a report. Several tools are used to analyze the data. Modeling tools enable an analyst to present graphic representations of a system. Data flow diagrams, for example, graphically show the flow of data through a system.

(3) The objective of systems design is to do a preliminary design, which describes the general functional capabilities of a proposed information system; then do a detail design, which describes how the system will deliver the capabilities described in the preliminary design; and then to write a report. Tools used in the preliminary design are CASE tools and project management software. CASE (computer-aided software engineering) tools are programs that automate the various activities of the SDLC in several phases. Prototyping refers to using workstations, CASE tools, and other software applications to build working models of system components that can be quickly tested. A prototype is just such a limited working system developed to test out design concepts. Project management software consists of programs used to plan, schedule, and control the people, costs, and resources required to complete a project.

(4) The objective of systems development is to develop or acquire the software, acquire the hardware, and then test the system. In considering what software to acquire, the systems analyst must make a make-or-buy decision decide whether to create a program or buy existing software.

(5) Systems implementation consists of converting the hardware, software, and files to the new system and training the users. Conversion to the next system may be by direct implementation (stop the old, start the new), parallel implementation (operate both old and new concurrently for a while), phased implementation (phase in new system in stages), or pilot implementation (try out new system by some users).

(6) Systems maintenance adjusts and improves the system by having system audits and periodic evaluations and by making changes based on new conditions.