Principles of Information Systems Eighth Edition Chapter 12 Systems Development: Investigation and Analysis

An Overview of Systems Development

Participants in Systems Development Systems Analysts Specialize in analyzing & designing business systems. Stakeholders Benefit from the systems develop- ment effort Programmers Modify/develop programs to satisfy user requirements. Users Interact with the system regularly

Initiating Systems Development

Information Systems Planning

Developing a Competitive Advantage Creative analysis Investigates new approaches to existing problems. Critical analysis Unbiased & careful questioning of whether system elements are related in the most effective/ efficient ways. When translating a strategic plan into an IS plan, many companies want to plan systems that will improve their competitive advantage. To do this, creative and critical analyses are both required. Creative analysis means looking at problems or opportunities in different ways and using novel methods to address them. Critical analysis involves looking at the system in an unbiased way and questioning whether all elements of the system are related in the most effective and efficient way. Automating an existing manual system could mean you’ll be doing a flawed process faster. Underlying business processes should be examined and improved before they are automated. Critical analysis means questioning the status quo. Related to this is questioning assumptions – sometimes a new system is requested when improving the underlying business processes is the solution.

Establishing Objectives for Systems Development Performance objectives Output quality or usefulness Output format quality or usefulness Speed at which output is produced Cost objectives Development costs Fixed investments Ongoing operating costs Uniqueness costs Systems should be designed with specific performance and cost objectives. These will also be used to evaluate the finished system. Typical performance objectives include ensuring right output for a user or process, in the right format. Response time is also typically important. In web development, the time it takes a typical user to download a web page is usually important.

Systems Development Life Cycles Since it is an ongoing process, the systems development process is also called the systems development life cycle, or SDLC. While a system is built, there are various deadlines and deliverables. But even after it is installed and accepted, the life of the system continues as it is maintained. Eventually, most information systems will be retired, and the cycle starts over to replace them.

Systems Development Life Cycles

The Traditional Systems Development Life Cycle

Factors Affecting Systems Development Success Degree of Change Continuous Improvement versus Reengineering Managing change

Factors Affecting Systems Development Success Managing Change Requires the ability to recognize existing or potential problems & deal with them before they become a serious threat to the success of the new/ modified system

Project Management Project schedule Project milestone Project deadline Critical path Project management involves planning, scheduling, directing, and controlling resources for a task to accomplish to specific objectives. A project schedule details activities, personnel and other resources allocated to each activity, and expected completion date. A project milestone is a critical date for the completion of a major part of the project. The project deadline is the date the entire project will be completed and the system will be operational. Large projects can be very complex and involve scheduling & managing thousands of different activities – some can be worked on at the same time, some must be done before others can be started. Each activity has an earliest start time, earliest completion time, and slack time. Slack time is the amount of time an activity can be delayed without delaying the whole project. The critical path contains all activities with no slack – that is, all activities that would delay the whole project if they were delayed.

Use of Project Management Tools

Use of Project Management Tools

Systems Investigation In general, systems investigation attempts to uncover answers to the following questions: What primary problems might a new or enhanced system solve? What opportunities might a new or enhanced system provide? What new hardware, software, databases, telecommunications, personnel, or procedures will improve an existing system or are required in a new system? What are the potential costs (variable and fixed)? What are the associated risks?

Participants in Systems Investigation

Feasibility Analysis Technical Feasibility: Can the hardware, software, & other system components be acquired or developed to solve the problem? Operational Feasibility: Can the project be put into action or operation? Schedule Feasibility: Can the project be completed in a reasonable time? Economic Feasibility: Does the project make financial sense?

The Systems Investigation Report

Systems Analysis After the system has been approved for further study, systems analysis begins. During systems analysis, the development team describes what the proposed system must do to solve the problem or exploit the opportunity. The entire system is evaluated, along with associated business processes, since it is often not wise to automate existing processes. The analysis team, consisting of IS and functional area staff and managers, studies the existing system, determines requirements for the new system, and evaluates alternative solutions. Systems analysis includes data analysis and requirements analysis. The main output of systems analysis is a description of systems requirements in order of their priority.

Identifying Sources of Data

Collecting Data

Data Analysis Data modeling Activity modeling Application flowcharts Grid charts CASE tools After the data is collected, it must be studied to determine the efficiency and effectiveness of the existing system and changes that are needed. In data analysis, the development team puts the data into a usable form to study the flow of data, the objects, and the relationships in the system. Many tools and techniques exist to do this – we’ll look at several, including data modeling, activity modeling, and applications flow charts.

Requirements Analysis Asking directly Critical success factors (CSFs) The IS plan Screen and report layout Requirements analysis identifies user, stakeholder, and organizational needs for the new or modified system. This involves studying problems they are having with the current system and improvements they suggest. When a system is clear-cut and users clearly understand their needs for the new system, asking them to tell you works well. However, when needs aren’t so clear, the systems analyst must find other ways to elicit requirements. One approach asks mangers to list factors that are absolutely critical to the success of their mission – such as availability of raw materials, a customer list, or knowing the location of each technician reporting to him. The analyst can use these critical success factors to determine the outputs the system should provide. Inputs, processing, and performance details could then be determined. The IS plan addresses long-term IS requirements. If this is referred to when identifying requirements for a specific system, it is more likely that the system will fit into the long-term plan.

The IS Plan

Screen and Report Layout

The Systems Analysis Report

Summary Systems development team - of stakeholders, users, managers, systems development specialists, and various support personnel Five phases of the traditional SDLC - investigation, analysis, design, implementation, and maintenance and review Systems investigation participants - stakeholders, users, managers, employees, analysts, and programmers