Chapter 5

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Chapter 5

Systems Analysis

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What is Systems Analysis ?

Systems analysis – a problem-solving technique that decomposes a system into its component pieces for the purpose of studying how well those component parts work and interact to accomplish their purpose.

Systems design – a complementary problem-solving technique (to systems analysis) that reassembles a system’s component pieces back into a complete system—hopefully, an improved system. This may involves adding, deleting, and changing pieces relative to the original system.

Information systems analysis – those development phases in an information systems development project the primarily focus on the business problem and requirements, independent of any technology that can or will be used to implement a solution to that problem.

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Systems Analysis Phases

• Scope Definition Phase• Is the project worth looking at?

• Problem Analysis Phase• Is a new system worth building?

• Requirements Analysis Phase• What do the users need and want from the new system?

• Logical Design Phase• What must the new system do?

• Decision Analysis Phase• What is the best solution?

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Key Terms for Scope Definition PhaseSteering body – a committee of executive business and system managers that studies and prioritizes competing project proposals to determine which projects will return the most value to the organization and thus should be approved for continues systems development. • Also called a steering committee.

Project charter – the final deliverable for the preliminary investigation phase. A project charter defines the project scope, plan, methodology, standards, and so on. • Preliminary master plan includes preliminary schedule and

resource assignments (also called a baseline plan).• Detailed plan and schedule for completing the next phase of the

project.

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Sample Request for System Services

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Sample Problem Statements

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Key Terms of the Problem Analysis Phase

Cause-and-effect analysis – a technique in which problems are studied to determine their causes and effects.

In practice, effects can be symptomatic of more deeply rooted problems which, in turn, must be analyzed for causes and effects until the causes and effects do not yield symptoms of other problems.

Definition of Reengineering

The fundamental rethinking and radical redesign of core business processes to achieve dramatic improvements in critical performance measures such as quality, cost, and cycle time.

Source: Adapted from Hammer and Champy, Reengineering the Corporation, 1993

What Business Reengineering Is Not?

Automating: Paving the cow paths. (Automate poor processes.)

Downsizing: Doing less with less. Cut costs or reduce payrolls. (Creating new products and services, as well as positive thinking are critical to the success of BPR.)

Reengineering Might be ...

Obliterate what you have now and start from scratch.

Transform every aspect of your organization.

Source: Michael Hammer, “Reengineering Work: Don’t Automate, Obliterate,” Harvard Business Review, July-August, 1990, pp. 104-112.

Business Process Reengineering Life Cycle

Define corporate visions and business goals

Identify business processes to be reengineered

Analyze and measure an existing process

Identify enabling IT & generate alternative process redesigns

Evaluate and select a process redesign

Implement the reengineered process

Continuous improvement of the process

VisioningVisioning

IdentifyingIdentifying

AnalyzingAnalyzing

RedesigningRedesigning

EvaluatingEvaluating

ImplementingImplementing

ImprovingImproving

Reengineering Example

Which line is shorter and faster?

Cash LaneNo more than 10 items

Reengineered Process

Key Concept: • One queue for

multiple service points

• Multiple services workstation

19 steps, 5 departments, 19 persons

Issuance application processing cycle time: 24 hours minimum; average 22 days

But: only 17 minutes in actually processing the application!

Department AStep 1

Department AStep 2

Department EStep 19

. . . .

Issuance Application

Issuance Policy

Insurance Policy Process Before Reengineering

*Source: Adapted from Rethinking the Corporate Workplace: Case Manager at Mutual Benefit Life, Harvard Business School case 9-492-015, 1991.

Case Manager

UnderwriterPhysician

Mainframe

LAN Server

PC Workstation

• application processing cycle time: 4 hours minimum; 3.5 days average

• application handling capacity doubled

• cut 100 field office positions

Insurance Policy Process After Reengineering

Criteria for BPR ProjectsImprovement Goals

BusinessReengineering

FunctionalProcess

Improvement

Business as Usual

Scope Role of IT

Cross Function/Organization

Function

Task

Status Quo Radical

Incidental

Fundamental

Symbolic Intense

Senior Management Involvement

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Cause-and-Effect (POOC) Analysis

What are the Problems?

You need to:• Solicit input

• Identify problems that currently exist, have been experienced in the past and are expected to recur, or could occur in the future

• Identify the conditions under which these problems occur

• Prioritize the problems identified

Problems typically identify some existing condition, along with a desired future state.

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Problem Analysis - 1

Goals are often very general concepts, e.g.• Efficiency, Quality, Fairness, Health, Happiness, …

Objectives are operational definitions of goals; a measure of success. It is something that you expect to achieve, given sufficient resources.• Reduce the number of uncollectible customer accounts

by 50 percent within the next year.• Increase by 25 percent the number of loan

applications that can be processed during an eight-hour shift.

• Decrease by 50 percent the time required to reschedule a production lot when a workstation malfunctions.

Problem Analysis - 2.

Constraint – something that will limit your flexibility in defining a solution to your objectives. Constraints are requirements that you cannot change, e.g.

• The new system must be operational by April 15.• The new system cannot cost more than $350,000.• The new system must interact with our suppliers’ systems, using

their predefined protocols.• The new system must bill customers every 15 days.

Three types of constraints• Natural - bound by the laws of nature• External - enforced by outside agents• Perceived - assumed to be undesirable, prohibited or impossible

Sometimes you need to challenge constraints.

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System Improvement Report OutlineI. Executive summary (approximately 2 pages)

A. Summary of recommendationB. Summary of problems, opportunities, and directivesC. Brief statement of system improvement objectivesD. Brief explanation of report contents

II. Background information (approximately 2 pages)A. List of interviews and facilitated group meetings conductedB. List of other sources of information that were exploitedC. Description of analytical techniques used

III. Overview of current system (approximately 5 pages)A. Strategic implications (if project is part of or impacts

existing IS strategic plan)B. Models of the current system

1. Interface model (showing project scope)2. Data model (showing project scope)3. Geographical models (showing project scope)4. Process model (showing functional decomposition only)

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System Improvement Report Outline (cont.)I. Analysis of the current system (approx. 5-10 pages)

A. Performance problems, opportunities, cause-effect analysisB. Information problems, opportunities, cause-effect analysisC. Economic problems, opportunities, cause-effect analysisD. Control problems, opportunities, cause-effect analysisE. Efficiency problems, opportunities, cause-effect analysisF. Service problems, opportunities, and cause-effect analysis

II. Detailed recommendations (approx. 5-10 pages)A. System improvement objectives and prioritiesB. ConstraintsC. Project Plan

1. Scope reassessment and refinement2. Revised master plan3. Detailed plan for the definition phase

III. AppendixesA. Any detailed system modelsB. Other documents as appropriate

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Group Exercise

• Create a Cause-and-Effect (POOC) analysis and matrix for your group project.

• Due: via email to the Professor before next class meeting

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• Requirements Analysis Phase• What do the users need and want from

the new system?• Logical Design Phase

• What must the new system do?


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Key Terms of Requirements Analysis Phase Functional requirement – a description of

activities and services a system must provide.• inputs, outputs, processes, stored data

Nonfunctional/quality requirement – a description of other characteristics that define a satisfactory system

• Performance, ease of learning and use, budgets, deadlines, documentation, security, internal auditing controls

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Key Terms of Requirements Analysis Phase (cont.)

Use case – a business scenario or event for which the system must provide a defined response. Use cases evolved out of object-oriented analysis; however, their use has become common in many other methodologies for systems analysis and design.

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Key Terms of Requirements Analysis Phase (cont.)

Timeboxing – a technique that delivers information systems functionality and requirements through versioning.

1. The development team selects the smallest subset of the system that, if fully implemented, will return immediate value to the systems owners and users.

2. That subset is developed, ideally with a time frame of six to nine months or less.

3. Subsequently, value-added versions of the system are developed in similar time frames.

• A mandatory requirement is one that must be fulfilled by the minimal system, version 1.0

• A desirable requirement is one that is not absolutely essential to version 1.0. It may be essential to the vision of a future version.

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Requirements Discovery

Requirements discovery – the process, used by systems analysts of identifying or extracting system problems and solution requirements from the user community.

The World of Requirements

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Requirements Discovery Methods

• Fact-finding – the process of collecting information about system problems, opportunities, solution requirements, and priorities. • Sampling existing documentation, reports, forms, databases,

etc• Research of relevant literature• Observation of the current system• Questionnaires and surveys• Interviews

• Joint requirements planning (JRP) –use of facilitated workshops to bring together all of the system owners, users, and analysts, and some systems designer and builders to jointly perform systems analysis. • Considered a part of a larger method called joint application

development (JAD), a more comprehensive application of the JRP techniques to the entire systems development process.

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Model-Driven Analysis Methods

Model-driven analysis – a problem-solving approach that emphasizes the drawing of pictorial system models to document and validate both existing and/or proposed systems. Ultimately, the system model becomes the blueprint for designing and constructing an improved system.

Model – a representation of either reality or vision. Since “a picture is worth a thousand words,” most models use pictures to represent the reality or vision.

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Model-Driven Approaches

• Traditional Approaches• Structured Analysis

• Focuses on the flow of data through processes• Key model: data flow diagram

• Information Engineering• Focuses on structure of stored data• Key model: entity relationship diagram

• Object-Oriented Approach• integrates data and process concerns into objects

• Object – the encapsulation of the data (called properties) that describes a discrete person, object, place, event, or thing, with all the processes (called methods) that are allowed to use or update the data and properties. The only way to access or update the object’s data is to use the predefined processes.

• Key model: Unified Modeling Language (UML) diagrams

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A Simple Process Model

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A Simple Data Model

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A Simple Object Model

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Accelerated Systems Analysis

Accelerated systems analysis approaches emphasize the construction of prototypes to more rapidly identify business and user requirements for a new system.Prototype – a small-scale, incomplete, but working sample of a desired system.• Accelerated systems analysis approaches

• Discovery Prototyping• Rapid Architected Analysis

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Discovery Prototyping

Discovery prototyping – identify the users’ business requirements by having them react to a quick-and-dirty implementation of those requirements.• Advantages

• Prototypes cater to the “I’ll know what I want when I see it” way of thinking that is characteristic of many users and managers.

• Disadvantages• Can become preoccupied with final “look and feel” prematurely• Can encourage a premature focus on, and commitment to, design• Users can be misled to believe that the completed system can be

built rapidly using prototyping tools

Types of Diagrams

Data flow diagrams (DFDs) show the flow of data from external entities into the system, how the data moves from one process to another, as well as logical storage.

Context DiagramA (DFD) of the scope of an organizational system that

shows the system boundaries, external entities that interact with the system and the major information flows between the entities and the system.

Level-O DiagramA data flow diagram (DFD) that represents a system’s

major processes, data flows and data stores at a high level of detail.

DFD Notation

Rectangles are external entities: sources or destinations of data.

Rounded rectangles are processes, which take data as input, do something to it, and output it.

Arrows are the data flows, which can either be electronic data or physical.

Open-ended rectangles are data stores, including databases or XML files, as well as physical stores such as or filing cabinets.

D Customer 1 Master

Packing slip

1

AddCustomer

New customer

Context Diagram

8.438.43

Level-0 DFD

8.448.44

OrderSystemCustomer Warehouse

Order

Invoice

New customer

Picking Slip

Order

Ship Statement

Example Context Diagram for an Order Processing System

New customer

1

AddCustomer

New info

D Customer 1 Master

Customer

2

ProcessCustomer

Order

OrderCust Info

D Back 3 Order

D Inventory 2 Master

BackorderProc Info

3Warehouse

Picking Slip

ProducedPending Order

Packing slip Warehouse

4

Shipping Prepare

D Customer 1 Master

Ship N/A

5

CustomerBill

Produce

Bill N/A

Bill Info

Shipping B/O info

Order

Picked

Customer

Ship statement

Cust Bill

DFD for Order Entry

Customer

2.1

VerifyCustomer

OrderD Customer 1 Master

Need to establish

Customer

2.2

Verify Item

OrderD Inventory 2 Master

Notify

Valid

2.3

CheckAvailable

2.4

UpdateCommit

2.5

Create Order

D Inventory 2 Master

D Shipping 4 Taxes

D Back 3 Order

Valid Item

Back Order

Avail

Update

Tax

Ord

Pending Order

Breakdown of 2 (Process Customer Order)

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Key Terms of Decision Analysis Phase

• Technical feasibility – Is the solution technically practical? Does our staff have the technical expertise to design and build this solution?

• Operational feasibility – Will the solution fulfill the users’ requirements? To what degree? How will the solution change the users’ work environment? How do users feel about such a solution?

• Economic feasibility – Is the solution cost-effective?

• Schedule feasibility – Can the solution be designed and implemented within an acceptable time period?

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Candidate Systems Matrix

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Candidate Systems Matrix (cont.)

Feasibility Analysis Matrix - 1

This matrix complements the candidate systems matrix with an analysis and ranking of the candidate systems. • The columns of the matrix correspond to the

same candidate solutions as shown in the candidate systems matrix.

• Some rows correspond to the feasibility criteria already discussed (e.g. cost, schedule).

• Rows are added to describe the general solution and a ranking of the candidates.

• The cells contain the feasibility assessment notes for each candidate.

Feasibility Analysis Matrix - 2

Each row is assigned a weight for each criterion.

Each candidate is scored for each criterion.

After scoring all candidates on all criteria, a final score is recorded in the last row.

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Feasibility Analysis Matrix - 3.

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Typical System Proposal OutlineI. Introduction

A. Purpose of the report

B. Background of the project leading to this report

C. Scope of the report

D. Structure of the report

II. Tools and techniques used

A. Solution generated

B. Feasibility analysis (cost-benefit)

III. Information systems requirements

IV. Alternative solutions and feasibility analysis

V. Recommendations

VI. Appendices

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Group Exercise

• Create a Feasibility analysis and matrix for your group project.

• Decide on your chosen approach and justify why it is a reasonable one, e.g.:• What are the improvement objectives and priorities?

• How does your approach meet these objectives?

• What other approaches were considered and why were they rejected?

• Due: before next class meeting

Documents

Chapter 5