MIS Bus system analysis exam

STUDY GUIDE FOR EXAM 2 – MIS 300 / MIS 301

CAVEATS (Latin for ‘warnings’):

· DO NOT ASSUME THAT YOU CAN READ THIS AND BE READY FOR THE EXAM

· ASSUME THAT ANYTHING IN THE CHAPTERS MAY BE COVERED IF THEY ARE NOT SPECIVICALLY INCLUDED HERE

· THERE WILL BE SOME ACTUAL DIAGRAMMING USING DFD SYMBOLS ON THE EXAM

CHAPTER 4 – INFORMATION GATHERING / INTERVIEWING

· There are four interactive methods for obtaining information requirements:

· Interviewing

· Stories

· Joint application design

· Using questionnaires to survey

· Interviewing is an important method for collecting data on information system requirements, as well as a tool for exploring the human-computer interaction concerns.

· Interviewing reveals goals, feelings, opinions, and informal procedures.

· Five steps in planning the interview are:

· Reading background material

· Establishing interview objectives

· Deciding whom to interview

· Preparing the interviewee

· Deciding on question types and structure

· There are two basic types of interview questions: openended or closed.

· Probes are used to obtain additional information.

· There are three basic ways of structuring interviews: pyramid, funnel, or diamond.

· Stories originate in the workplace, are shared with and repeated by, coworkers and are used to relay some kind of information.

· Isolated stories are welcome when you are looking for facts, and the more important enduring stories capture all aspects of the organization.

· JAD may be used when:

· Users are restless and want something new.

· The organizational culture supports joint problem-solving behaviors.

· Analysts forecast an increase in the number of ideas using JAD.

· Personnel may be absent from their jobs for the length of time required.

· JAD involves analysts, users, executives, observers, a scribe, and a session leader.

· Questionnaires are useful in gathering information about attitudes, beliefs, behaviors, and characteristics from key organization members.

· Questionnaires are valuable if organization members are widely dispersed, if many members are involved with the project, if exploratory work is needed, or if problem solving prior to interviews is necessary.

· Questionnaire language should be simple, specific, free of bias, not patronizing, technically accurate, and addressed to those who are knowledgeable. Use software to check whether the reading level is appropriate for the respondents.

· Questionnaires must be valid and reliable.

· There are three problems associated with poorly constructed scales:

· Leniency

· Central tendency

· Halo effect

· Good response rates can be achieved with consistent control of questionnaire format and style, and with meaningful ordering and clustering of questions.

· Administrating a questionnaire electronically has many benefits, such as reduced costs, and collecting and storing the results electronically.

CHAPTER 6 – AGILE METHODS AND PROTOTYPING

· Prototyping is an information-gathering technique useful for supplementing the traditional systems development life cycle.

· Prototypes are useful in seeking user reactions.

· NOTE: I won’t ask about the four types of Prototypes (“Patched-up” etc.)

· Prototyping may be used as an alternative to the systems development life cycle.

· Guidelines for developing a prototype are:

· Work in manageable modules

· Build the prototype rapidly

· Modify the prototype in successive iterations

· Stress the user interface

· One disadvantage of prototyping is that managing the prototyping process is difficult because of its rapid, iterative nature. A second disadvantage is that incomplete prototypes may be regarded as complete systems. Clear communication of the prototype timetable with users is essential.

· One advantage of prototyping is the potential for changing the system early in its development. A second advantage is the opportunity to stop development on an unworkable system. A third advantage is the possibility of developing a system that closely addresses users’ needs and expectations.

· Sometimes COTS software may be the quickest way to create a prototype.

· Systems analysts must work systematically to elicit and evaluate users’ reactions to the prototype. There are three ways the user is involved:

· Experimenting with the prototype

· Giving open reactions to the prototype

· Suggesting additions to and/or deletions from the prototype

· Agile modeling is used to plan quickly, develop and release software quickly, and revise software quickly.

· There are four values that are important to agile modeling:

· Communication

· Simplicity

· Feedback

· Courage

· The activities of agile modeling are:

· Coding

· Testing

· Listening

· Designing

· The four resource control variables in agile modeling are:

· Time

· Cost

· Quality

· Scope

· The four core practices in agile modeling are:

· A short release time

· Working a 40-hour week

· Having an onsite customer

· Pair programming

· An agile modeling process has the following steps:

· Listen for user stories from the customer.

· Draw a logical workflow model for the user story.

· Create new user stories based on the logical model.

· Develop some display prototypes.

· Use feedback from the prototypes and logical workflow diagrams to develop the system until a physical model is created.

· User stories are written that consist of a dialogue between developers and users.

· An agile modeling approach called Scrum is based on team development within a strict time frame.

CHAPTER 7 – USING DATA FLOW DIAGRAMS

· Data flow diagrams (DFDs) are one of the main methods available for analyzing data-oriented systems.

· Through the use of DFDs, which emphasize the logic underlying the system, the systems analysts can put together a graphical representation of data movement through the organization.

· The data flow approach has four main advantages over the narrative explanation of the data movement. They are:

· Freedom from committing to the technical implementation of the system too early

· Further understanding of the interrelationships of systems and subsystems

· Communicating current system knowledge to users through data flow diagrams

· Analysis of the proposed system to determine if all the data and processes have been defined

· Four basic symbols are used to chart data movement on data flow diagrams. They are:

· A double square for an external entity—a source or destination of data

· An arrow for movement of data from one point to another

· A rectangle with rounded corners for the occurrence of transforming process

· An open-ended rectangle for a data store

· Correct naming of data flow objects is necessary for good communication. Guidelines are:

· External entities should be named with a noun.

· Processes should be named:

· A system name

· A subsystem name

· With a verb-adjective-noun format

· Processes should have a unique reference number.

· Data stores should be named with a noun.

· Use the following guidelines to develop a data flow diagram:

· Make a list of business activities.

· Create the context level diagram, including all external entities and the major data flow to or from them.

· Create Diagram 0 by analyzing the major activities within the context process. Include the external entities and major data stores.

· Create a child diagram for each complex process on Diagram 0. Include local data stores and detailed processes.

· Processes that do not create a child diagram are called primitive processes. Logic is written for these processes.

· The following conditions are errors that occur when drawing a data flow diagram:

· A process that has only input data flow to it or only output data flow from it.

· When data stores or external entities are connected directly to each other, in any combination.

· Incorrectly labeling data flow or objects. Examples are:

· Labels omitted from data flow or objects

· Data flow labeled with a verb

· Processes labeled with a noun

· Too many processes on a data flow diagram. Nine is the suggested maximum.

· Omitting data flow from the diagram.

· Unbalanced decomposition between a parent process and a child diagram. The data flow in and out of a parent process must be present on the child diagram.

· Logical data flow diagrams show how the business operates and include processes that would exist regardless of the type of system implemented.

· The progression of creating data flow diagrams is:

· Create a logical data flow diagram of the current system.

· Next, add all the data and processes not currently in the system which must be present in the new system, giving a logical data flow diagram for the new system.

· Finally, derive the physical data flow diagram for the new system.

· Advantages of logical data flow diagrams are:

· Better communication with users. They are familiar with how the business operates.

· More stable systems, because the design is based on a business framework.

· Increased understanding of the business by analysts.

· The system will have increased flexibility and be easier to maintain.

· Elimination of redundancy.

· Physical data flow diagrams show how the system operates or how the new system will be implemented.

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· Physical data flow diagrams include processes for adding, reading, changing, and deleting records. CRUD is an acronym for Create, Read, Update, Delete.

· A CRUD matrix shows which programs or processes add, read, update, or delete master file records.

· Master or transaction files are used to link all processes that operate at different times.

· An input flow from an external entity is sometimes called a trigger, because it starts activities.

· Elements (or fields) are categorized as either:

· Base elements that are keyed into the system

· Derived elements, which are the result of some operation, such as arithmetic or logic

· Creating a use case is another approach used to develop a data flow diagram. A use case shows the steps performed to accomplish a task.