Lecture Management information systems: Solving business problems with information technology – Chapter 12

In this chapter you will learn: How do you create the software tools needed for your organization? What main options exist for building information systems? How do you control a major development project? Why is control so important? Is SDLC always the best approach? What other methodologies could be used?,...

Introduction to MIS

Chapter 12 Systems Development

Systems Development

Operations Tactics

Dec

ision

supp

ort

system

Tra

nsaction

proc

essing

Systems development life cycle Prototyping

 Challenges in Building Information Systems

 Systems Development Lifecycle (SDLC)

 Cases: Government Agencies

 Appendix: Visual Basic

Project Evaluation (given a discount factor)

Get list of cost items from the user

(Description, value, time-incurred, probability-factor, category )

Examine each item in the list:

Compute the present value of the cost:

PV = Cost / ( (1 + rate) ^ time)

Multiply by the probability factor:

EV = probability * PV

If item is in a special category, Then add or subtract correction:

End If

Accumulate the total valueEnd of list

Return the Total value

Individual Development: Pseudocode

 2 - 5 times over budget

 2 - 5 times behind schedule

 Missing technical objectives

 Design problems

 Duplication of efforts

 Incompatibilities

 User/designer conflicts

Cafasso 1994

Success & Failure

 Reasons for Success

 Reasons for Failure

 Lack of user input

 Incomplete requirements

 Changing requirements and specifications

 Lack of executive support

 Lack of technical skills

SystemsImplementation

problems revisions problems revisions

Systems Development Life Cycle

Blue Print/Planning

Development Controls

 Detailed work plan

 Performance targets

 Practices & procedures

 User input & control

Customer Order Entry

Enter Salesperson Data

Enter/Change Customer Data

Enter Items Ordered

Review and Print Forms

Look up Item Numbers Check Inventory Status Special Orders

Customer Order Copy Shipping List Back Order List

Design Tools Visual Table of Contents

Purpose, Classification, Object Orientation, Decomposition

Comparison of Diagrams

 Data Flow Diagram

 Show process and flow of

 Structure Chart or VTOC

 Show modules and usage

Stage Procedure Approx Pct Of Effort

Analysis

Feasibility Requirements Conceptual Design

5 15 5

Design

Physical Design Programming Procedure Develop.

20 25 10

Implementation Conversion 15

Maintenance & Review

Review Maintenance

5 not included

G Davis and M Olson, Management Information Systems 1985.

SDLC Effort

Education and training

ChangingBusiness operations

 Recognize how the system

will affect the business

 Encourage users to change

 Implementation plans

old new

old

new

new new new new

dept or component 2 dept or component 3 dept or component 4

store 1 store 2 store 3 store 4

Implementation Options

System Evaluation

SDLC Advantages & Disadvantages

Build Initial Prototype

5) Process never ends

Prototyping

User

Prototyping Evaluation

 Advantages

 Get a working system earlier

 User has more input

 Designed to be modified

 Problems

 Need 4GL trained MIS staff

 Too many users

 Too many analysts

Object Orientation

Properties Methods Inheritance Polymorphism

Business Objects and Processes

Object Orientation

Object Classes

Customers Name

Address Phone Change Address Add New Customer Delete Customer

Commercial Contact

Account Representative

Contact Account Representative Year Started

Assign Account Rep

Individual

Object Properties/

Attributes Methods/

Functions

Object Example

SDLC versus Object Oriented

0 10 20 30 40 50 60

Requirements Analysis Design Implementation

Events Methods Objects

Sale Record Sale

Update Inventory

Notify Customer Service

Transaction LogAccounts & LedgersInventory

CustomersEmployees (commissions)

Developing systems is generally a team effort among MIS developers and

business users Groupware, CASE, and development tools are often used to facilitate communication and

coordination

Developing Systems with Teams

Control InformationSharing MonitoringChange

Access

Control

DataSharing

ConsistencyEnforcement

Concurrency

Teamwork Development

 Pre-packaged software limitations

 Takes User time

End-user Development When to Call for Help

 Many people use the system

 PC versus central computer

 Need documentation

 Individual user differences

 Need to train users

 Commercial software limits

 User time is expensive

 Mission critical application

 Additional testing

 Many modifications

 Need security & control

 Need to integrate

 Use corporate data

 Tie to existing software

 Connect to network

 Database Integrity

 Avoid duplicate data

 Changes to corporate data

Who Should Develop Systems?

 MIS

 Size: Many users

 Complexity: Different

departments

 Long development time

 SDLC large project controls

 Cost of user time

 Highly trained users

 How Can MIS Help?

 Easy access to data/database

 Advice and help

 Testing & quality control

 Training & tutorials

 Support/Help Center

SDLC RAD Objects JAD Prototyping End User

Time frame long short any medium short short

MIS staff many few split few one or two none

Interface minimal minimal Windows crucial crucial crucial

Document

& Training vital limited in objects limited weak none

Integrity &

Security vital vital in objects limited weak weak

Choosing Methodologies

Basic Systems

Input Process Output

A Systems Approach to Process Analysis

 Systems

 Input, Process, Output

 Divide and Conquer

 Goals and Objectives

 Control and Feedback

 Diagramming Systems

 Common Systems Problems

System boundary: The Zoo

MembersDonorsVisitors

Other Zoos

EducationVisitor Counts

EducationalMaterials

BabyAnimalsRegistration Papers

Health Data

TheZoo

Subsystems: The Zoo

Animal Care

Donor &

Public Relations

Manage Facilities

Produce Management Reports

Manage Human Resources

Goals and Feedback

Feedback

Control

Analyze Process

Data Flow Diagram Objects

External Entity

Data FlowFeedback and Control Data

The Zoo: Level 0

public/

zoo visitors donors

zoo booster members

1 donor and public relations

2

produce

mgt reports

3 manage human resources

4 animal care

5 manage facilities

needs & budgets animal requests

health research

maintenance schedule

maint &

building request

specialist request employee

pay data, requests receipts

Usage Management

reports

The Zoo: Level 1

1.1 produce PR & outreach programs

1.3 org booster services &

meetings

1.4 track needs and donor programs

1.5 produce accounting

money &

requests

newsletter notices, etc.

money &

suggestions

booster requests

donor lists

expenses & budget

money, data, visitor statistics

accounting reports

public requests animal

needs

Systems: Data Dictionary

 Processes

 Donor & Public Relations

Data Dictionary

System Problems

Do not include data flows between external entities Drop the line or make one of the

entities internal.

A process cannot invent data It must have a data flow coming in to it.

A process cannot be a black hole data must flow out of the process

Maybe it should

be a file instead.

Manufacturer Customer

Sell Products Invoices sales receipt

orders purchase orders

Inventory list

Distribute Educational Materials

Create Educational Materials Visitors

Problem Boundary

Problem: Shortages of Educational Materials

Zoo system boundary

Common Systems Problems

Check Customer Credit

Check Orders for Errors

money &

suggestions newsletter,

notices, etc.

plans booster requests

expenses & budget donor list &

animal needs

animal needs

& plans

Problems Some animal budgets have excess $

1.2 Handle donor requests

1.3 Booster services &

meetings

PR data receipts etc.

1.4 Track needs

& donor programs

Object name:

Object attributes/properties:

Object functions/methods:

Interest Rate Monthly Fees Pay Interest Compute Charges Print Quarterly Statement

Number Beginning Balance Name Ending Balance Client Current Balance Manager Interest Rate Date Opened

Open Acct Accept Deposits Close Acct Withdrawal

Pay Interest

Lowest Balance in Month Bad Check Charges Authorized Signature Print Monthly Statement Send Bad Check Notice Pay Interest

Rolling Thunder Order Entry Process

BikeSizes

Est sizes

Pricing

Select

Se lect

Ne

w o

Rolling Thunder Manufacturing Process

Rolling Thunder Purchasing Process

PurchaseOrder

PurchaseItems

ManufacturerTransaction

ble

Some Classes for Rolling Thunder

ConstructionWaterBottle…

CustomNameLetterStyleIDStoreID

EmployeeID

CustomerBikeTubes

SerialNumber

TubeNameTubeIDLength

BikeParts

SerialNumber

ComponentIDSubstituteIDLocationQuantity

… Manufacturer

ManufacturerID

ManufacturerNameContactName

Components

ComponentID

ManufacturerIDProductNumberRoad

CategoryLengthHeightWidthWeightDescriptionListPriceEstimatedCost

*

Rolling Thunder Bicycle Class Diagram

Cases: Government Agencies

Cases: Federal Aviation Administration

Internal Revenue Service

What is the company’s current status?

What is the Internet strategy?

How does the company use information technology?

What are the prospects for the industry?

www.faa.gov

www.irs.gov

Appendix: Visual Basic

Abs Absolute value

Atn Arc Tangent

Cos Cosine

Exp Exponential

Fix Returns integer portion

Int Converts to integer

StrComp Compare two strings

LCase, UCase Convert to lowercase or uppercase

Len Find length of a string

Format Format a string

InStr, Left, LTrim

Bonus = 0End If

Select Case Customer

Case Customer = ‘Corporate’

Discount = 0.05Case Customer = ‘Government’

Discount = 0.10Case Else

Discount = 0.01End Select

VB: Input and Output

Could use: InputBox, MsgBox, and Printer object

Generally just use data in the application

In this example, the form collects the data and displays the result

VBA: Excel Example

Sub Macro1()

' Keyboard Shortcut: Ctrl+Shift+U

For Each c In Selection

Snowbasin 154 Brighton 113 Park City 115 Deer Park 120