Information Systems - What Are They? Based on Chapter 1 of Bennett, McRobb and Farmer: Object Oriented Systems Analysis and Design Using UML, (4th Edition), McGraw Hill, 2010. © 2010 Bennett, McRobb and Farmer

In This Lecture You Will Learn: How to define an information system (IS) Some examples and types of IS How to use the concepts of systems theory to explain the parts and behaviour of IS How IS can be useful in managing organizations © 2010 Bennett, McRobb and Farmer

© 2010 Bennett, McRobb and Farmer Introduction Information systems (IS) are created by people They are used in all kinds of organisations They are important in our everyday lives All IS must be able to select, store, process and retrieve relevant data IS do not necessarily depend on digital IT (but most modern ones do) © 2010 Bennett, McRobb and Farmer

© 2010 Bennett, McRobb and Farmer IS in History IS have existed in some form throughout history: Ancient Mesopotamian records of grain in city storehouses (3500 BCE) Roman Empire records of property and tax 19th Century railway signalling systems The RAF’s communication and control system used during the Battle of Britain(1940) © 2010 Bennett, McRobb and Farmer

The Emergence of Modern IS Most IS today depend on digital electronic computers Earliest examples (in Second World War) include code-breaking Colossus Computer First business computer, Leo 1, built in 1951, used for routine transactions like payroll and managing inventory Modern IS used for vast range of purposes © 2010 Bennett, McRobb and Farmer

The Role of the Computer Computers carry out tasks also done by people and by other technologies Storage: signalman’s memory / hard disk Display: Battle of Britain map / PC screen Calculation: abacus / software program Communication: telephone line / LAN Typical advantages of computers: high speed, low cost, reliability Worth stressing that most things computers do can also be done without them. Many examples of ‘information work’ long pre-date modern information technology – railway signalling is a good example, but there are many others. Also worth getting the class to identify some disadvantages of using a computer. Examples: Loss of human involvement in decisions Inflexibility in unexpected circumstances Poor analysis or design can make some tasks impossible to perform Displacement of human skills Fragmentation and automation of work can lead to loss of valuable communication about the work © 2010 Bennett, McRobb and Farmer

McGregor On-Line Retail Site A typical modern IS with: Online catalogue display and shopping cart Back-office systems store stock details, orders, payment transactions, and more Communications link to credit-card processing centre Robot warehouse control system Delivery scheduling © 2010 Bennett, McRobb and Farmer

© 2010 Bennett, McRobb and Farmer IS are Systems © 2010 Bennett, McRobb and Farmer

Characteristics of Systems Every system has: Inputs and outputs A purpose (related to transformation) A boundary and an environment Subsystems and interfaces Control using feedback and feed-forward Some emergent property Emergent properties, in particular, will almost certainly need further explanation. One good example given by Ed Yourdon (I can’t remember the specific source) was the analyst who turned to a colleague and said “you are certainly more than the sum of your parts – you are an idiot!” The point being that if you look at the parts that make up a person, it would be difficult to find idiocy at any level of analysis other than a holistic view of the whole person. A useful exercise would be for the class to suggest examples of systems and identify examples of each feature for these. © 2010 Bennett, McRobb and Farmer

© 2010 Bennett, McRobb and Farmer Elements of an IS Every IS must have: A human activity that needs information Some stored data An input method for entering data Some process that turns the data into information An output method for representing information May also have: Subsystems that we can also regard as systems Interfaces with other systems © 2010 Bennett, McRobb and Farmer

System Transformation All useful systems transform their inputs into useful outputs For IS, inputs are typically data or information and outputs are typically also information This transformation is the whole reason for building and operating the system It must render the input data useful in some new way That all useful systems produce useful outputs is clearly a tautology, but still an important point. It is worth spending a little time on getting the class to identify useful transformations for some example systems, and discuss how these are related to wider goals. © 2010 Bennett, McRobb and Farmer

Transformation Example McGregor’s Delivery Scheduling System may have inputs: Information about orders, available stock, customer addresses, vehicle capacities… …And may have outputs: Which orders to load on each vehicle, what route the vehicle should follow… How does this benefit McGregor? To pick up an earlier point, you could ask the class if this system must necessarily be automated. If it is, what are the likely costs and benefits? © 2010 Bennett, McRobb and Farmer

© 2010 Bennett, McRobb and Farmer Are Systems Real? Maybe, maybe not! Systems thinking is useful because it helps to analyse and understand problems What matters is the understanding you achieve You can choose to see anything as a system, whether or not it really is one © 2010 Bennett, McRobb and Farmer

Systems and the Real World © 2010 Bennett, McRobb and Farmer

Systems and Subsystems © 2010 Bennett, McRobb and Farmer

© 2010 Bennett, McRobb and Farmer Types of IS Information Systems are used to support people’s activities Store and retrieve information Carry out calculations Aid communication Control and schedule work Other support …. ? © 2010 Bennett, McRobb and Farmer

© 2010 Bennett, McRobb and Farmer Types of IS (cont’d) Operational Systems assist or control business operations An Accounting System replaces costly and error-prone human clerks Management Support Systems help managers to decide or to communicate A Delivery Scheduling System helps decide how to load and route the delivery trucks This slide could be used to pick up some ethical aspects of automation, especially the possible effects on individuals and communities when jobs are automated. I would not, however, recommend the over-simplification that displacing jobs is always a bad thing. There is little evidence that IT has reduced employment overall. Rather, it has restructured the employment market, replaced some jobs with others, and changed the nature of others (some for better and others for worse). © 2010 Bennett, McRobb and Farmer

© 2010 Bennett, McRobb and Farmer Types of IS (cont’d) Real-time Control Systems typically operate physical equipment, often in safety-critical settings Some cars have an Engine Management System to control fuel supply and ignition © 2010 Bennett, McRobb and Farmer

How Do IS Relate to the Human Activity System? We can view an organization as a system, perhaps with many subsystems Ideally, each subsystem helps the overall system fulfil its purpose IS are also subsystems and should help to meet goals of people in the organization © 2010 Bennett, McRobb and Farmer

Strategy and Planning for IS Value Chain analysis is one popular way to analyse an organisation: Managers can focus on IS that help each of the critical activities along the ‘chain’ © 2010 Bennett, McRobb and Farmer

Multiple Strategies for IS and IT © 2010 Bennett, McRobb and Farmer

© 2010 Bennett, McRobb and Farmer Summary In this lecture you have learned about: What an information system is Some examples and types of IS Basic concepts of systems theory, and how to apply them to understanding IS How IS are related to organizations © 2010 Bennett, McRobb and Farmer

© 2010 Bennett, McRobb and Farmer References Bennett, McRobb and Farmer (2010) Checkland and Holwell (1998) (For further bibliographic details, see Bennett, McRobb and Farmer) © 2010 Bennett, McRobb and Farmer