Clarke, R. J (2000) SL909-00: 1 BUSS 909 Supplementary Lecture 00: Information Theory & Systems...

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Clarke, R. J (2000) SL909-00: 1

BUSS 909BUSS 909

Supplementary Lecture 00:

Information Theory & Systems TheoryInformation Theory & Systems Theory

Office Automation & IntranetsOffice Automation & Intranets

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AgendaAgenda

Discuss two basic ideas in IS Discuss two basic ideas in IS Theory:Theory:–General Systems ModelGeneral Systems Model

–Data and InformationData and Information

At the end of the lecture you At the end of the lecture you should understand that the basic should understand that the basic IS theory is flawedIS theory is flawed

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Information Systems Theory:Information Systems Theory:a very brief introductiona very brief introduction

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Information Systems Information Systems TheoryTheory

Information Systems Discipline = Information Systems Discipline = Concepts of Concepts of ‘Systems’ ‘Systems’ + + ‘Information’‘Information’

both ‘systems’ and ‘information’ both ‘systems’ and ‘information’ have considerable have considerable theoreticaltheoretical, , methodologicalmethodological and and substantivesubstantive problems, ie/ are problems, ie/ are problematicproblematic

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General Systems Model General Systems Model Applied to OrganisationsApplied to Organisations

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General Systems ModelGeneral Systems ModelDevelopmentDevelopment

Contrary to what you may believe Contrary to what you may believe (or may have been taught) the IS (or may have been taught) the IS Discipline did not develop the Discipline did not develop the concept of the systemconcept of the system

in fact the ‘General Systems in fact the ‘General Systems Model’ was in Model’ was in wide circulation wide circulation well before computers were well before computers were inventedinvented

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understanding how we understanding how we gotgot and how we and how we useuse ‘general ‘general systems’ tells us a great deal systems’ tells us a great deal about disciplines in general about disciplines in general (and IS in particular)(and IS in particular)

the General Systems Model the General Systems Model dates from the late 1920s-dates from the late 1920s-1930s 1930s

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the work originates in Biologythe work originates in Biology useful concepts emerge in useful concepts emerge in

population dynamics (Lotka population dynamics (Lotka c.1907 and later)c.1907 and later)

developed as a general model developed as a general model for biology (von Bertalanffy for biology (von Bertalanffy c.1930s; 1968)c.1930s; 1968)

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Basic System ElementsBasic System Elements

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System BoundarySystem Boundary

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SystemSystem

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EnvironmentEnvironment

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External EntitiesExternal Entities

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External Entity 1External Entity 1

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Data Flow 1Data Flow 1

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Data SourcesData Sources

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Data SinkData Sink

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Context DiagramContext Diagram

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Basic System ElementsBasic System ElementsReview of ConceptsReview of Concepts

System BoundarySystem Boundary SystemSystem EnvironmentEnvironment External EntitiesExternal Entities Data Sources and Data SinksData Sources and Data Sinks Context DiagramContext Diagram

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Levels of a SystemLevels of a SystemAn AnimationAn Animation

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Processes or SubsystemsProcesses or Subsystems

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Level 1Diagram 0

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Level 1Diagram 0 Process 1.0

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Level 1

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Level 1

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Level 1

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Level 1

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Level 1

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Level 1

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Level 2Diagram 2.0

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Level 2Diagram 2.0 Process 2.1

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Level 2

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Level 2

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Level 2

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Level 2

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Level 2

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Level 2

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Level 3Diagram 2.4

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Level 3Diagram 2.4 Process 2.4.1

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General Systems ModelGeneral Systems ModelPropogation or SpreadPropogation or Spread

entered sociology/political entered sociology/political science in 1950s and 1960sscience in 1950s and 1960s

the view of systems theorists is the view of systems theorists is that the general concept of a that the general concept of a system can be applied to system can be applied to social social systems systems ie. organisationsie. organisations

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Closed SystemsClosed Systems

some systems are some systems are closedclosed – they are not influenced by their they are not influenced by their

environment, eg. solar systemenvironment, eg. solar system

–have have entropyentropy which describes how which describes how these systems use up energy and these systems use up energy and run down run down

not useful to ISnot useful to IS

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Open SystemsOpen Systems

social systems are social systems are open open systemssystems–can can importimport energy from the energy from the

environmentenvironment

–can can sustainsustain themselves in response to themselves in response to changes in their environmentchanges in their environment

–possess possess negentropynegentropy, and can achieve , and can achieve new states new states

they they adaptadapt

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Organisations as Systems Organisations as Systems (1)(1)

Organisations are open system Organisations are open system (contrast with closed systems)(contrast with closed systems)

a a physical system physical system of the firm of the firm transforms input resources into transforms input resources into output resourcesoutput resources

input resources come from input resources come from environment, output resources go environment, output resources go to environment to environment

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Organisations as Systems Organisations as Systems (2)(2)

physical resources:physical resources:–material flow material flow (from suppliers to customers)(from suppliers to customers)

–personnel flow personnel flow (from the labour market and (from the labour market and back)back)

–machine flow machine flow (from supplier to scrap yard)(from supplier to scrap yard)

–money flow money flow (from owners who provide (from owners who provide investment capital and customers who buy investment capital and customers who buy goods)goods)

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Organisations as System Organisations as System (3)(3)

TransformationProcess

OutputResources

InputResources

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Closed Loop Systems Closed Loop Systems (1)(1)

some open system can control some open system can control operations, some cannotoperations, some cannot

when no feedback loop is provided when no feedback loop is provided for an open system then it is called for an open system then it is called an an open-loop systemopen-loop system

when feedback loop and control when feedback loop and control mechanism exists -mechanism exists -closed loop closed loop systemsystem

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Closed Loop Systems Closed Loop Systems (2)(2)

control is provided by a loop- control is provided by a loop- called a called a feedback loopfeedback loop

feedback consists of signals feedback consists of signals are sent to provide a are sent to provide a corrective action corrective action

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Closed Loop System Closed Loop System (3)(3)

Control Mechanism

OutputResources

InputResources

Signal Feedback

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Physical System of an Organisation Physical System of an Organisation as a controlled systemas a controlled system

Management

OutputResources

InputResources

Signal

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Information is Gathered from all Information is Gathered from all Physical System ElementsPhysical System Elements

Management

OutputResources

InputResources

Information Data

additional data-gathering activties at input and processing parts of the physical system

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Information Processor Information Processor transforms data into information for transforms data into information for

Management purposesManagement purposes

Management

OutputResources

InputResources

InformationProcessor

Information Data

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Performance Standards added to Performance Standards added to Management & Information ProcessorManagement & Information Processor

Management

OutputResources

InputResources

Standards

Information Data

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Changes to Physical SystemChanges to Physical SystemDecisonsDecisons are added are added

& some signals re/classified& some signals re/classified

Management

OutputResources

InputResources

Standards

DecisionsInformation Data

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General Systems ModelGeneral Systems Model

Management

OutputResources

InputResources

Standards

Decisions

Physical Information Data

Boundary

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Systems Approach to Systems Approach to Decision MakingDecision Making

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Problem-solving ElementsProblem-solving Elements

manager

standards

solution

problem

alternatesolutions

constraints

desired

current

Elements of the conceptual system

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Structured, Unstructured, Structured, Unstructured, Semistructured Problems Semistructured Problems (1)(1)

Management problems are often Management problems are often considered to be either structured considered to be either structured or unstructured in natureor unstructured in nature

Important criteria as these are Important criteria as these are used to identify different types of used to identify different types of system: Operational Systems, system: Operational Systems, MIS, and DSSMIS, and DSS

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Structured ProblemsStructured Problems–consist of elements and consist of elements and

relationships between elements relationships between elements which are understood by the which are understood by the problem solverproblem solver

–problem expressed in problem expressed in mathematical form and therefore mathematical form and therefore probablyprobably implementable implementable

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Unstructured ProblemUnstructured Problem–contains no elements or contains no elements or

relationships between elements relationships between elements which are understood by the which are understood by the problem solverproblem solver

–quantification of unstructured quantification of unstructured problems is difficult if not problems is difficult if not impossibleimpossible

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Semistructured ProblemSemistructured Problem–contains some elements or contains some elements or

relationships between elements relationships between elements that are understood by the that are understood by the problem solverproblem solver

–other elements or relationships other elements or relationships between elements may not be between elements may not be understood at allunderstood at all

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Is there such a thing as a Is there such a thing as a structuredstructured problem? This problem? This already presupposes a already presupposes a particular type of solution!particular type of solution!

computers can solve computers can solve structured problemsstructured problems

most managers deal with most managers deal with semistructured problemssemistructured problems

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Introduction to MIS Introduction to MIS (1)(1)

computers first applied to computers first applied to business tasksbusiness tasks– accounting functionsaccounting functions

– specific functional areas eg./ order entryspecific functional areas eg./ order entry

today computers used also to today computers used also to provide provide management management informationinformation

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as we will see the as we will see the information information needsneeds of Management are of Management are different from the information different from the information needs of other system usersneeds of other system users

also, management has also, management has special responsibilities and special responsibilities and obligations in organisations- obligations in organisations- require require managed informationmanaged information

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General Definition of MIS:General Definition of MIS: A A systems that provides the systems that provides the manager with information for manager with information for decision making.decision making.

Either, the Either, the general informationgeneral information needs of managers or, all needs of managers or, all managers in a managers in a specific specific functional areafunctional area

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MembersMembers of Organisationsof OrganisationsDistinct TypesDistinct Types

Strategic Planning LevelStrategic Planning Level– top level managers, long term view, organisational top level managers, long term view, organisational

wide scopewide scope

Management Control LevelManagement Control Level– middle level managers, regional managers, product middle level managers, regional managers, product

directors and division headsdirectors and division heads

Operational Control LevelOperational Control Level– where operations occur in the organisation, example where operations occur in the organisation, example

foreman in factoriesforeman in factories

OperationsOperations– workers, clerks etc...workers, clerks etc...

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Members of OrganisationsMembers of OrganisationsAssociated with ‘Hierarchy’Associated with ‘Hierarchy’

Strategic PlanningStrategic Planning

Management ControlManagement Control

OperationalOperational

Operational ControlOperational Control

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Categories of ISCategories of ISAssociated with ‘Hierarchy’Associated with ‘Hierarchy’

Increasing Increasing UncertaintyUncertainty

Strategic PlanningStrategic PlanningEIS, DSS, GDSS, ESEIS, DSS, GDSS, ES

Management ControlManagement ControlMIS (MkIS, MIS (MkIS,

OperationalOperationalTPS (EDP)TPS (EDP)

Operational ControlOperational ControlAIS, MISAIS, MIS

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Major Categories of MISMajor Categories of MIS

Major types of information Major types of information systems for managementsystems for management–Management Information Systems (MIS)Management Information Systems (MIS)

– Decision Support Systems (DSS)Decision Support Systems (DSS)

– Expert Systems (ES)Expert Systems (ES)

– Office Automation Systems (OA)Office Automation Systems (OA)

Linked to Operational Linked to Operational SystemsSystems

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Social Systems Social Systems considered harmfulconsidered harmful

in sociology...in sociology...““Although hugely influential at the Although hugely influential at the

time... [attempts] to found a new time... [attempts] to found a new general theory of... social systems general theory of... social systems [are] now adjudged a relative [are] now adjudged a relative failure” (Jary & Jary 1991, 649)failure” (Jary & Jary 1991, 649)

there are therefore some there are therefore some obvious questions...obvious questions...

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Isn’t ‘system’ OK for IS?Isn’t ‘system’ OK for IS?

couldn’t it be suitable for IS couldn’t it be suitable for IS but not suitable for sociology?but not suitable for sociology?–well this is possiblewell this is possible

–not likelynot likely

–we find some theoretical problems we find some theoretical problems with ‘systems’ as a way of modelling with ‘systems’ as a way of modelling workplaces workplaces

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Some technologies don’t fitSome technologies don’t fit

MIS do fit (EIS, DSS, GDSS, MIS MkIS, MIS do fit (EIS, DSS, GDSS, MIS MkIS, AIS etc) and therefore by definition AIS etc) and therefore by definition Operational Systems that feed them dataOperational Systems that feed them data

but others do not because they span all but others do not because they span all levels of the hierarchy, levels of the hierarchy, –Office AutomationOffice Automation

–EDI (Electronic Data Interchange)EDI (Electronic Data Interchange)

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Why use ‘system’Why use ‘system’

why does the information why does the information systems discipline still use it?systems discipline still use it?– to answer this question we look at to answer this question we look at

why sociology thinks ‘social why sociology thinks ‘social systems’ are a failuresystems’ are a failure

‘‘conservative’ assumptions conservative’ assumptions about the about the integration of social integration of social systemssystems

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levels of abstraction levels of abstraction that are that are removed from the workplaceremoved from the workplace

tautologytautology relative neglect of the independent relative neglect of the independent

influence of individual members influence of individual members agencyagency

ignoring the effects of ignoring the effects of cultureculture on on development and use of ISdevelopment and use of IS

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there are there are alternativesalternatives to ‘social to ‘social system’ explanations of system’ explanations of organisationsorganisations–webswebs

– language-basislanguage-basis

we will look at these in later we will look at these in later Lectures (5-13)Lectures (5-13)

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Data & InformationData & Information

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Information SystemsInformation SystemsTypical DefinitionTypical Definition

“ “[An information system]...is a [An information system]...is a grouping of people, objects and grouping of people, objects and procedures... [providing] information procedures... [providing] information about the organization and its about the organization and its environment... which is environment... which is usefuluseful to to members and clients of that members and clients of that organization”organization”

Paraphrase Avison and Fitzgerald (1988, 1)Paraphrase Avison and Fitzgerald (1988, 1)

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data is easy to identifydata is easy to identify data is created with purposes in data is created with purposes in

mindmind but but informationinformation depends on who, depends on who,

what, where, how and whenwhat, where, how and when for closed, biological systems for closed, biological systems

the idea of information is great!the idea of information is great!

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organisations are not organisations are not axiomaticaxiomatic (rule determined)(rule determined)

the members can the members can changechange the the internal and external processes internal and external processes of the organisationof the organisation

information becomes difficult to information becomes difficult to define/changes- just ask any define/changes- just ask any systems developersystems developer

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Data & InformationData & Information concept of information relies on concept of information relies on

Shannon & Weaver (c. 1940s)Shannon & Weaver (c. 1940s) defines information in terms which defines information in terms which

exclude exclude meaningmeaning in other words the second basis of our in other words the second basis of our

discipline (the concept of information) discipline (the concept of information) is is theoretically inappropriate theoretically inappropriate for use for use when developing systemswhen developing systems

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Information SystemsInformation SystemsDefinitional ProblemsDefinitional Problems

analysis, design and analysis, design and implementation practices focus implementation practices focus on the on the peoplepeople, , objectsobjects andand proceduresprocedures

rarely focus on the rarely focus on the useuse of of systems- the purposes of systems- the purposes of systems in given organisational systems in given organisational contextscontexts

Clarke, R. J (2000) SL909-00: 1 BUSS 909 Supplementary Lecture 00: Information Theory & Systems...

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