Rapid application development:
Team-based technique that speeds up information systems development and produces a functioning information system.
(JAD only a requirements model, RAD does that as well as actually make the product)
Cons: stresses the mechanics of system itself, does not emphasize the company’s business needs. Short time might produce a product of less quality, and consistency. Overall risky
Pros: develops product quickly with significant cost savings.
Joint application development:
User-oriented technique for fact-finding and requirements modeling.
(Involves users more.)
Cons:
More expensive and can be cumbersome if too many people involved.
Pros:
more accurate statement of requirements, better understanding of goals, stronger commitment to the success of new system.
Agile Method:
Attempt to develop a system incrementally, but building a series of prototypes and constantly adjusting them to user requirements. Uses continuous feedback.
Pros: flexible and efficient with change. Stress team interaction and community based values.
Frequent ‘final products’ validate the product and reduce risk.
Cons: high level technical and interpersonal skills. Lack of structure and documentation can leak to risk factors. Project can change significantly over time due to changing user requirements.
Functional Decomposition Diagram (FDD):
Top-down representation of a function or process. Shows business functions and breaks them down from top to bottom.
Business process modeling (BPM):
Describes one or more business processes; (such as handling an airline reservation, filing a product order, updating a customer account.)
Uses a standard language: Business process modeling notation (BPMN)
Scrum:
Type of agile development method, derived from the rugby term scrum, involves intense interaction but more mental than physical.
(Pigs and chickens)
Data Flow Diagrams:
Show how a system stores, processes and transforms data but does not show program logic or processing steps. What, not how.
Unified modeling language (UML):
Widely used method of visualizing and documenting software systems design. Uses object oriented design concepts but independent of a specific programming language. (Pseudo code)
Use-Case Diagram
Visually represents the interaction between users and the information system. User becomes an “actor” with a specific role showing how he/she interacts with the system.
Sequence diagrams:
Shows the timing of interactions between objects as the occur.
Systems requirement:
Characteristic or feature that must be included in an info. System to satisfy business requirements and its users.
Fall into 5 categories:
- outputs
- inputs
- Processes
- performance
- controls
Examples of output, system requirement:
- the website must report online volume statistics every 4 hours, and hourly during peak periods.
- the contact management system must generate a daily reminder list for all sales reps.
- the purchasing system must provide suppliers with up-to-date specifications
Examples of input, system requirements.
- the department head must enter overtime hours on a separate screen.
- student grades must be entered on machine-scannable forms prepares by the instructor.
- each input form must include date,time, product code, customer number, and quantity.
Examples of process, system requirements:
- the student records system must calculate the GOA at the end of each semester. (Key word calculate)
- the human resources system must interface properly with the existing payroll system.
- The video rental system must not execute new rental transactions for customers who have overdue videos.
Examples of performance, system requirements.
- the system must support 25 users online simultaneously.
- response time must not exceed 4 seconds.
- the student records system must produce class lists within five hours after the end of registration.
Examples of control, system requirements.
- system must provide log-on security at the operating system level and at the application level.
- system must maintain separate levels of security for users and the system administrator
- all transactions must have audit trails
Scalability:
the systems ability to handle increased traffic (business volume/transactions).
Deliverable:
Something that is physically given, that shows progress. Could be a prototype.
Fact finding involves 5 questions. And in each of these questions you must also ask ‘why.’
- Who? Who performs the procedures in the system. Why? Are the the correct people? Could other people do it?
- What? What is being done? Why? Why is that process necessary.
- Where? Where the operations are being performed? Why? Where could they be performed? Where could they be performed more efficiently.
- When? When is a procedure performed? Why Is is performed in that manner?
- How? How Is a procedure performed? Why is it performed in that manner?
Interviews. (everything about them.)
Planned meet to obtain info from someone.
Seven general steps for an interview:
- determine people to interview
- informal structure: some people have more influence or knowledge in a company than appears on an organization chart. - Establish objectives for interview
- find general areas, then specify certain facts you want. - Develop questions
- Avoid “leading questions” that suggest/favor a particular reply. - Prepare for interview
- pick a place, let interviewee know how long it’ll last.
- let interviewee know of questions/documents before interview via email
- neutral location or interviewees office
- Conduct the interview
- make interviewee feel at least
- engaged listening (notice verbal and non verbal communication)
- summarize and seek confirmation at end of interview of your understanding of the discussion.
6. Document interview - take notes and record information directly after interview.
- tape recorders are effective but make interviewee uneasy.
- Evaluate the interview
- identify biases.
Document review (fact finding technique)
Helps one understand how the current system is supposed to work by analyzing forms and operating documents currently in use.
Observation (fact finding technique)
Actual observation of the system in action to gain a better understanding of it.
Types of interview questions:
-Open ended:
encourage spontaneous and unstructured responses. Better to understand s larger process and draw the interviewees opinions/suggestions.
-closed ended:
Limit the response. Used to find specific info. Or to verify facts
-range-of-response:
Closed-ended questions that ask the person to evaluate something by providing limited answers to specific responses or on a numeric scale. (1-10)
Total Cost of Ownership (TCO):
Costs, both indirect and direct that apply to making/running an information system.
