Business Information Systems Essay
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1. What is a decision? When does a person have to make a decision? A decision is a conclusion or resolution reached after a thought out consideration of variables in a problem. When more than one possible action is involved in solving a problem, a decision must be made. 2. Calculating a complex trajectory of a spaceship to Mars is a structured problem, whereas diagnosing the cause of a rash on a person’s skin is often unstructured. How so? A structured problem is one in which an optimal solution can be reached through a single set of steps.
Since the one set of steps is known, and since the steps must be followed in a known sequence, solving a structured problem with the same data always yields the same solution. This sequence of steps is known as an algorithm. An unstructured problem is one for which there is no algorithm to follow to reach an optimal solution— either because there is not enough information about the factors that might affect the solution or because there are so many potential factors that no algorithm can be formulated to guarantee a unique optimal solution.
Unstructuredness is closely related to uncertainty.
3. DSSs use models to process data. Explain what a model is. Give an example that is not mentioned in the chapter. A sequence of events or a pattern of behavior might become a useful model when the relationships among its inputs, outputs, and conditions can be established well enough that they can be used to analyze different parameters. Models are used to predict output on the basis of different input or different conditions or to estimate what combination of conditions and input might lead to a desired output. Models are often based on mathematical research or on experience. A model might be a widely used method to predict performance, such as best- fit linear analysis, or it might be built by the organization, using the experience that employees in the firm have accumulated over time. 4. Many DSSs are not stand- alone anymore, but are embedded in other ISs. What are those ISs? Many DSSs are now closely intertwined with other organizational systems, including data warehouses, data marts, and ERP systems, from which they draw relevant data. 5. What is a sensitivity test?
A sensitivity analysis is conducted to test the degree to which the total profit grows or shrinks if one or more of the factors is increased or decreased. It is often referred to as what- if analysis.
6. The airline and hospitality industries use DSSs for yield management. What is yield management, and what is the output of a yield management DSS? The purpose of yield management DSSs is to find the proper pricing to maximize the overall revenue from selling seats for each flight. The result is often price discrimination.
7. What is the purpose of an expert system? How can it serve as a competitive tool? The purpose of ESs is to replicate the unstructured and undocumented knowledge of the few (the experts), and put it at the disposal of the many other people who need the knowledge, often novices or professionals in the same domain but with far less expertise. It can serve as a competitive tool by the using of a knowledge base, which is a collection of facts and the relationships among them. An ES does not use a model module but an inference engine. The inference engine is software that combines data that is input by the user with the data relationships stored in the knowledge base. The result is a diagnosis or suggestion for the best course of action. In most ESs, the knowledge base is built as a series of IF- THEN rules. 8. Explain how expert systems can distribute expertise.
By coupling quantitative data from a database with decision models. An expert system (ES) is developed to emulate the knowledge of an expert to solve problems and make decisions in a relatively narrow domain. 9. How could an ES be used to detect probable fraud committed by a bank employee? Business applications have increasingly combined neural nets and ES technologies in software that monitors business processes and supply chain management. Neural nets have been very effective in detecting fraud of many types.
10. What is the advantage of combining ES and neural net technologies? ES researchers continue to look for ways to better capture knowledge and represent it. They test the results of such efforts in highly unstructured problem- solving domains. Rather than containing a set of IF- THEN rules, more sophisticated ESs use neural networks (neural nets), programs that are designed to mimic the way a human brain learns. An ES is constructed with a set of rules, but as data on real successes and failures of decisions is accumulated and fed into the system, the neural network refines the rules to accomplish a higher success rate. 11. What is a GIS? What purpose does it serve?
GISs process location data and provide output. For instance, a GIS could be used to help a housing developer determine where to invest by tracking and displaying population changes on a map, highlighting in color increases of more than 10 percent over the past three years. 12. Name the three major elements that are combined to make up a GIS. A typical GIS consists of (1) a database of quantitative and qualitative data from which information is extracted for display, (2) a database of maps, and (3) a program that displays the information on the maps. Chapter 11
1. What is business intelligence?
Business intelligence (BI) mainly refers to computer-based techniques used in identifying, extracting, and analyzing business data, such as sales revenue by products and/or departments, or by associated costs and incomes. 2. What is OLAP, and why is it often associated with visual cubes? OLAP is an approach to swiftly answer multi-dimensional analytical (MDA) queries. It is another type of application used to exploit data warehouses. Although OLAP might not be as sophisticated in terms of the analysis conducted, it has extremely fast response time and enables executives to make timely decisions. Each side of the cube provides another two dimensions of relevant information.
3. What is the advantage of using a dimensional database rather than on- the- fly processing in OLAP? Tables, even if joining data from several sources, limit the review of information. Often, executives need to view information in multiple combinations of two dimensions. 4. Why is online analytical processing usually conducted on warehoused data or dimensional databases rather than on data in transactional databases? To speed up response and summarize that data and organize the information in dimensional databases for OLAP. 5. What is “ drilling down”?
A process by which one starts with a table that shows broad information and successively retrieves tables of more specific information. Chapter 12
1. Why is IT planning so important?
* Creating a corporate and IT mission statement. * Articulating the vision for IT within the organization. * Creating IT strategic and tactical plans. * Creating a plan for operations to achieve the mission and vision. * Creating a budget to ensure that resources are available to achieve the mission and vision 2. As part of their IT planning, many organizations decide to standardize. What does standardization mean in this context, and what are its potential benefits? One major goal— and advantage— of planning is standardization. When management decides to adopt a certain IT resource for all its units, regardless of function or location, it standardizes its IT. Benefits would be: * Cost saving * Efficient training * Efficient support
3. Why is traditional systems development referred to as a “ cycle”? What determines the cycle’s end? Because it consists of several distinct phases that are followed methodically, and the developers complete the phases sequentially. The SDLC approach assumes that the life of an IS starts with a need, followed by an assessment of the functions that a system must have to fulfill that need, and ends when the benefits of the system no longer outweigh its maintenance costs, or when the net benefit of a new system would exceed the net benefits of the current system. 4. Systems developers often use the term “ application development” rather than “ systems development.” Why? It involves fast development of an application based on initial user requirements and several cycles of user input and developer improvements.
5. What are the benefits of using data flow diagrams? Who benefits from DFDs? The use of only four symbols and the simplicity of DFDs are their great advantage. Those who benefit are external entities include individuals and groups of people who are external to the system, such as customers, employees, other departments in the organization, or other organizations. 6. SDLC is usually recommended for developing an IS that will be interfaced to other ISs. Give two examples of an IS that is interfaced with at least two other ISs. The better known methods are Extreme Programming (XP), Adaptive Software Development (ASD), Lean Development (LD), Rational Unified Process (RUP), Feature Driven Development (FDD), Dynamic Systems Development Method (DSDM), Scrum, and Crystal.
7. Recall the discussion of IT professionals in Chapter 1, “ Business Information Systems: An Overview”. Of the following professionals, who does the majority of the systems construction job: the CIO, systems analyst, database administrator (DBA), or programmer? Why? Systems analyst, because it takes a specialist to analyze and determine the type of program made to improve the system. 8. What are the advantages of agile methods over waterfall development methods, such as the traditional SDLC? What are the risks? The differences among the methods are outside the scope of this discussion. However, the major advantage of all agile methods is that they result in fast development of applications so that users can have them within weeks rather than months or years. Users do not have to wait long for system modifications, whether they are required because of programmer errors or because users have second thoughts about some features.
However, the benefits of agile methods do not come without risks. First, the analysis phase is minimal or is sometimes eliminated completely. Reducing or skipping a thorough formal analysis increases the risk of incompatibilities and other unforeseen mishaps. Also, the develop-ers devote most of their time to construction and little time to documentation, so modification at a later date can be extremely time consuming, if not impossible. Because of the inherent risks, there are times when agile methods are appropriate and others when they are not.
9. Why are agile methods so helpful when users cannot define system requirements? Agile methods encourage users’ involvement throughout the process and encourage developers to change requirements in response to user input if needed. The purpose of agile methods is not to conform to a static contract with the users but to ensure that the users receive an application with which they are happy. Critics of agile programming in general and XP in particular argue that the relaxed approach to planning as well as ceding decision making and accountability to clients (users) might result in disasters, especially if such methods are applied to large, complex projects.
10. An increasing number of IS professionals prefer to call the end users of their creations “ customers,” even if the developers and users are employees of the same organization. Why? The customers of software development, the users, are not an adverse party and should not be negotiated with but regarded as codevelopers and co- owners of the software. 11. What is systems integration?
The process of linking together different computing systems and software applications physically or functionally, to act as a coordinated whole. 12. Why is systems integration more complicated when the systems involve the Web than when they do not? Systems integration is often much more complicated than systems development, because it requires the IT professionals to make different applications communicate with each other seamlessly. The complexity is multiplied when integrating ISs of several organizations that must work together over the Web. 13. The emergence of the Web as a vehicle for business increased the need for systems integration. How so? The web allows for remote access and because more legacy databases are integrated into new enterprise applications it makes for a smooth transition of data traffic.