Slide 1 MIT5312: Professor KirsSystems Concepts Introduction A Brief Overview of System Concepts and...

MIT5312: Professor Kirs Systems Concepts Introduction

A Brief Overview of System Concepts and

Terms


Why are we taking this course???Good Question!!

1. Its required2. The course you really wanted wasn’t available3. The course fits your schedule

No, Really – I don’t want to be a Systems Analyst Be quiet – I Do!!

Whether you do or don’t, you will somehow be involved with an information system:

1. Purchase Decision,2. Analysis,3. Design, or4. Implementation


Alright, Alright – Where do we start???With some basic concepts and terminology

Sounds boring ---Maybe – But necessary

??? Why ???

• To ‘level’ the playing field• So that we are all aware of the same

basic concepts• So that we are all speaking the

same language• Because I have some time to kill

and enjoy torture students


Systems

“a group of independent but interrelated elements comprising a unified whole”

• A system may be defined as:

• ALL the components must work together toward a single goal

• In fact it is many different and related systems that appear to be only one system

• It is a term that we use everyday, without thought to what it really means:

“I don’t understand why they chose the new inventory system instead of an SAP system”


Systems• Basic system characteristics:

• A system is viewed as a single “thing”“The neighbors have a new TV surround-around System”

• A system is not isolated“They can’t get the rear speakers to work with the DVD player”

• If any component collapses, the entire system collapses“Can you believe they paid all that money for a system that doesn’t work”

• A system appears complicated“I don’t know why they sell systems like that that no one can understand”

• A system will eventually collapse“Too bad the old system broke – It was much easier”

• A system is Synergistic“When they had everything working together, it was a thing of beauty”


Systems• Some System Elements:

• Thermostat: To control temperature

• Stereo System: To provide music

• Digestive System: Break-Down Foods

Purpose: The reason for thesystem’s existence.

• Ecosystems: Maintain the environment

Sometimes we can clearly define a system’s purpose:

Sometimes we can imply a system’s purpose:

Sometimes we aren’t really sure:

• The Solar System( But we know it is a system)


Systems• System Elements

Purpose: The reason for the system’s existence. Subsystems: A component of a system which is a

system in its own right. (Also called components)




system in its own right. (Also called components)Boundary: The extent of the system.

Environment: Everything outside the boundary that relates to the system.

Inputs: Items enter the system from the environment.

Outputs: items that exit the system.

Rental Car






Inputs: Items enter the system from the environment. Outputs: Items that exit the system. Interfaces: Connections between

the system and its environment, can be used for security, filtering.






Inputs: Items enter the system from the environment. Outputs: Items that exit the system. Interfaces: Connections between the system and its

environment, can be used for security, filtering. Constraints: Factors acting to limit the

functioning of the system (Controls).


Systems• Basic principles associated with Systems:

• Decomposition: being able to breakdown a systems into its components (reductionism)

• dealing with smaller, less complex processes

??? Why ???• System-wide processes are too complex• Consider a stereo system. It contains:

• Bass Volume• Woofers• Tweeters

WE CAN CONTROL THE OVERALL SOUND DELIVERED ONLY BY CONTROLING THE INDIVIDUAL COMPONENTS




• Modularity: results from decomposition; degree to which the system can be seen as a collection of self contained subsystems

??? Why ???• Again, it is an issue of complexity• It we couldn’t break down our stereo system into:

• A Tuner• A CD Player• A Tape Player

Each component a system itself

WE WOULD NOT BE ABLE TO DEAL WITH THE INDIVIDUAL COMPONENTS





• Coupling: the degree to which subsystems are dependent on each other.

??? Why ???• We must understand the relationships between the components

• If we didn’t know that the CD player worked off the tuner

WE WOULD NOT BE ABLE TO GET THE CD PLAYER TO WORK






• Cohesion: the extent to which a system or subsystem performs a single function.

??? Why ???• All of the components of the system must appear to work together

THINK OF ALL THE COMPONENTS INVOLVED IN AN A/V SURROUND-ARROUND SYSTEM WITH A CABLE, DVD, VCR, ETC.


Systems• Systems may be classified into 2 major types:

• Closed Systems: Those which do not interact with the environment

• Open Systems: Open systems are organic and must interact with their environment in order to maintain their existence

• Consider a stand-alone computer system

• Consider an internet computer


Systems• Closed Systems:

• Mechanical systems are generally closed systems

To use a refrigerator you turn it on and set the temperature. After that you can forget about monitoring the temperature because it is done automatically.

• You might consider a prison system as a closed system (especially if a prisoner is locked-up in isolation)

• A simple computer program which always returns the same result may be considered a closed system


Systems• Open Systems:

• Living Organisms

• Some mechanical systems, such as thermostats, which rely on inputs from the environment

People are open systems since they must interact with their environment in order to take in food, water, and obtain shelter

and produce affects affecting the environment


Information Systems• The emphasis here is that we are once again dealing

with a SYSTEMSYSTEM, not just an isolated program

• An information system is an relationship between:

• People• Functional Areas• Data• Organizational processes• Specific Processes• Interfaces• Networks• Information Technologies


Information Systems• Information systems should be viewed the same as any

other system

• The solar system• A railway system• An ecological system• An economic System

(The European Community)

• They are:

• ALL the components work together toward a single goal

“a group of independent but interrelated elements comprising a unified whole”


Information Systems• Information Systems have the same characteristics of all

Systems :

• An Information system is viewed as a single “thing”“I hate the new accounting system”

• A system is not isolated“The A/R system doesn’t correspond to the General Ledger”

• If any component collapses, the entire system collapses“The system doesn’t work because the A/R system is messed-up”

• A system appears complicated“I don’t understand why the A/R system needs all those entries”

• A system will eventually collapse“Too bad the old system broke – It was much easier”

• A system is Synergistic“When they had everything working together, it was a thing of beauty”


Information Systems• Information systems share the same system parameters

Purpose: The reason for the existence of the system.“We need an inventory system”

Subsystems: A system component which is also a system“It must have automatic reordering capabilities”

Boundary: The extent of the system“Due to budgetary constraints, we can’t include bulk discounts”

Environment: Everything outside the boundary that relates to the system.“Inputs will be made only by the supervisors in the inventory department”

Inputs: items that enter the system from the environment.“Additions to inventory will be made by scanning the new item UPC codes and entering the amounts manually”


Information Systems• Information systems share the same system parameters

Purpose: The reason for the existence of the system. Subsystems: A system component which is also a system Boundary: The extent of the system Environment: Everything outside the system boundaries Inputs: items that enter the system from the environment. Outputs: items that exit the system

“The system will produce reports of weekly, monthly and yearly consumption by item and by category”

Interfaces: Connections between the system and its environment; can be used for security, filtering.“Entry to the system will be password protected”

Constraints: internal and external factors which act to limit in some way the functioning of the system (Controls).“To assure accuracy, all additions must be double-entered”


Information Systems• A basic system can be represented as

Input

Control

OutputProcessing

FeedbackSignals

ControlSignals

ControlSignals

FeedbackSignals

ENVIRONMENT


Information Systems• Information Systems also share the same basic principles

associated with Systems:• Decomposition: being able to breakdown a systems into its

components (reductionism)



• Cohesion: the extent to which a system or subsystem performs a single function.

??? Why ???We will see that when we discuss how we go about analyzing and

designing information systems


Information Systems• For our purposes, we should realize that an information

system’s sole purpose is to add value to the organization

• Many failed systems were abandoned because analysts tried to build wonderful systems without understanding the organization or the users of the system.

• An information system must support and improve the day-to-day operations in a business (Data Processing)

• An information system must support and improve the problem solving and decision making needs of management (Information Services/Decision Support)

• An information system should provide the organization with a competitive edge (Strategic Advantage)


Information vs. Data• While information systems rely on data, they must provide

information

What’s the difference???

• Data (pl) is a non-random sequence of symbols

Fernandez, Juan A19 1211 83 77 81

• Information, while generally based on data, is something that increases our knowledge

Juan Fernandez is an Accounting Major and has a 80.3 average in Principles of Accounting

(Based on analysis of the above data)


The Value of Information

• Relevance - How useful is the information to the user?

• Information has a number of measures of value:

• Does it help the user perform their job better?• Does it make the user’s job easier?• Does the user feel more confident about the results?

• Accuracy - Extent of errors in the outputs• Are more appropriate decisions being made?

• Completeness - Does it cover all the important aspects?• Are important components missing?

• Timeliness – Is the information delivered when needed?• Is the data out of date?

• Reliability - What is the source of the information?• Can the validity of the data be shown?


The Value of Information

• Relevance - How useful is the information to the user?

• Information has a number of measures of value:

• Accuracy - Extent of errors in the outputs• Completeness - Does it cover all the important aspects?• Timeliness – Is the information delivered when needed?• Reliability - What is the source of the information?• Verifiability - ability to check or cross check the data

• Can the outputs be duplicated?

• Understandable - Can the user comprehend the information?• Is the information too complex?

• Economical - how much does it cost to produce?• Is the information worth it?

• Flexible - how many purposes can it serve?• Can the information be used for multiple applications?


What is Systems Analysis and Design???What is Systems Analysis and Design???

• Systems AnalysisSystems Analysis is the study of a business problem for the purpose of recommending improvements and specifying the business requirements for the solution

• Systems DesignSystems Design is the specification of a technical, computer-based solution for the business requirements identified in the systems analysis

(Note that programming is NOT required)


Who is involved in the Information Systems Who is involved in the Information Systems Development Process ???Development Process ???

• The Manager (the person in charge)• Systems Designer (Systems Analyst)• The User (The person who will actually use the system)

• The Systems Trinity:

Systems Analyst

Managers

Users

ALL of whom must be involved in the development process (Or the system will probably fail)


?? How does that work ???? How does that work ??

• System failure can be caused by any of the participants:

• A bad design by the Systems Analyst

• Lack of User Involvement in the design and implementation

• Lack of Manager Support

(Especially at the upper levels)

• The Systems Trinity should be viewed as a three-legged stool:


?? How are managers involved ???? How are managers involved ??

• S/he is responsible for the department or functional area productivity

• S/he is responsible for the costs involved in system development

• S/he is the person who must report to top management

• Ultimately, the manager is responsible for the system

I am the boss!!

• S/he is the person who ultimately must approve of the system


• In the 1980’s, A Cruise Ship Line Noticed they had a problem: • What Was a Large Source of Revenue?

-- Gambling (as soon as they were in International Waters)

• Unlike Casinos, they couldn’t have high ceilings with sophisticated surveillance

• Space is at a premium

• Gambling was not so large a business that they expend all the resources needed

?? Why Involve Users ???? Why Involve Users ??


• What Could they do? • Ask Customers not to cheat

• Put in a lot of surveillance Cameras

-- For some odd reason, gamblers did not seem to enjoy themselves much with a battery of cameras staring at them



• What did they do? • They hired a consulting firm dealing in electronic

(computerized) security systems

• A simple system for the Black Jack Table• Cards would be coated• At the end of each hand, the cards would be swept into a

slot, where they would be read

• What did they come up with?

• Statistical calculations would be made about who was naughty and nice

• Expensive? • About $15M

-- Chump-change for an organization that large



• Was the System built? • Yes – by the consulting firm

• JustJust before they installed it, the company decided that they had better show the users (black jack dealers) how to use the system

• What happened?

• And? • Well, what do you usually find at a Black Jack Table?• Cards

• Chips

• Drinks

-- Absolutely!



• And? • A strange thing happened:

• By AccidentAccident, within an hour or so, all of the dealers knocked over a customer’s drink, which just happened to spill into the hardware (the slot where the cards were swept), ruining the circuitry

• And then? • A lot of managers in Miami started looking for new jobs

The Moral of the Story:


Treat users like mushrooms and they will poison you !!


Why do businesses need Systems Analysts ???Why do businesses need Systems Analysts ???

• As we will see, originally, they didn’t

• Systems/Programs were straight-forward and only programming

• Now, systems analysts are needed to bridge the communications gap between those who need the computer and those who understand the technology.

• This reflects the change in required analyst skills• From technical to oral and written

communication skills


What does a Systems Analyst do???What does a Systems Analyst do???

• Study business problems and opportunities and then transform business and information requirements into computer-based information systems

• Sell the system to managers and users

• Supervise technical staff in the implementation of the chosen system


Where does a Systems Analyst work???Where does a Systems Analyst work???

That used to be a very simple question:

• In the traditional business environment, Information services were centralized for the entire organization

• Analysts worked along side programmers in permanent teams to develop programs for a specific functional area

• In Information Services Centers, or development Centers, they still do as:

• Systems/Applications Developers

• Data Administrators• Network/Telecommunications Administrators


Where does a Systems Analyst work???Where does a Systems Analyst work???

Now it is much more complicated:

• With the development of information systems and end-user computing, analysts may work in any area of the organization:

• End-User Consultants

• Help desk Advisors

• Installation/Training Providers

• And others

(More on this later)


What skills must an Analyst have???What skills must an Analyst have???• General Business Knowledge

• The ability to merge organizational objectives, functional needs, technology, and user requirements

• Problem Solving Skills

• The ability to analyze problems in terms of cause and effect rather than in terms of simple remedies

• Interpersonal Skills

• The ability to relate to managers, users and technical staff


What skills must an Analyst have???What skills must an Analyst have???• General Business Knowledge• Problem Solving Skills

• The ability to communicate effectively, both orally and in writing

• Interpersonal Skills• Communication Skills

• Flexibility/Adaptability• No two systems development are the same; the

analyst must learn to change their approaches to meet needs

• Technical Skills• Although programming is not as important as before, the

analyst must still be aware of the latest technology and understand and appreciate programming concepts

(A good programmer can not necessarily be a good analyst)


What career opportunities are available???What career opportunities are available???• According to the Bureau of Labor statistics, opportunities

for Systems Analysts are expected to increase much faster than the average for all professions

• The number of systems analysts increased by approximately 250,000 between 1998 and 2000 (36% increase

• Systems Analysis is ranked as the 12th fastest growing occupation


Anything else I should know about systems Anything else I should know about systems and systems analysts ???and systems analysts ???

Of Course!!! That’s why you’re taking this course !!

??? Any Questions ?????? Any Questions ???

I’ve got lots of questions, but I know that no one else does, and I hate to look stupid --- BETTER TO JUST NOT KNOW!!!

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