1. CB1004 Modelling Business Systems 51 Modelling Business Systems 5 Information and Communication

2. CB1004 Modelling Business Systems 52 Information Data is not information Information consists of data Holism – the whole is more than the sum of the parts Emergent properties – properties that apply to the whole but not the individual parts The way we build information has changed 1970’s HR record – text and numerical items 2000’s likely to include video clips, digital images

3. CB1004 Modelling Business Systems 53 Editing Visual message Letter symbol Green pixel Blue pixel Red pixel Constructing information from data

4. CB1004 Modelling Business Systems 54 Information Soft concept Words like old, football, vegetarian carry associations beyond the dictionary definition Can be loaded Hyperbole – use of exaggerated ways of representing information Take the word ‘Trauma’ Question begging Information presented as an unchallenged answer to an unasked question Given that this is the best book you've ever read…..

5. CB1004 Modelling Business Systems 55 Loading cont. Special pleading – something is fact before it’s been tested Lets be honest ……. To disagree implied dishonesty False objectivity – opinion presented as fact False concatenation – linking things together to imply they share a common feature when they don’t ‘Gays, women and other minorities…’ but women are the majority of the population

6. CB1004 Modelling Business Systems 56 Capturing data All observation disturbs what it observes Heisenberg Uncertainty Principle In physics the only way to find out the position of an electron is to reflect radiation off it, BUT the radiation moves the electron. BUT what you see is where it was not where it is now Hence talk in terms of probabilities Hawthorne plant in US Experiments to adjust plant lighting to improve worker performance found it impossible to separate one particular adjustment from other factors

7. CB1004 Modelling Business Systems 57 Classifying data Classes and categories for summarising data E.g insurance data may look at classes of ‘male’ and ‘22-year old’ to estimate frequency of accidents and costs of repairs

8. CB1004 Modelling Business Systems 58 Turning data into information Data – every weather reading for every station for every day last year Information – aggregating this data gives picture of global warming (or not)

9. CB1004 Modelling Business Systems 59 Interpreting the information Information is by nature ‘fuzzy’ Global warming – temperature higher than average or lower than average Hard data includes degree of probability The stock figures are accurate Demand will increase as forecast

10. CB1004 Modelling Business Systems 510 Usefulness of data More useful? Demand will be between 0 and 100 per month, any one figure is as probable as another Or demand will be between 47 and 53 with 90% probability of being 50 Entropy – looks at distribution of information, the wider the distribution of figures the less useful it is

11. CB1004 Modelling Business Systems 511 Communicating information General communication system model# Communication is an emergent property of a system Communication is between at least two people Good system methodology recognises we need to understand the soft issues behind what people seek or do not seek, to communicate about their needs from a system and their role in it.

12. CB1004 Modelling Business Systems 512 How do we communicate clearly Standard set of symbols Date 12/1/02 – UK 12 January 2002, in US is 1 December 2002 Diagrams Use of structured English – standard set of defined words Use an encoder, channel and decoder Encoder – computer program encodes information to digital signals Channel – telephone lines Decoder – computer translating signals to visual material

13. CB1004 Modelling Business Systems 513 Barriers to communication Environmental disturbance of originator or receiver Tiredness, dishonesty Noise Hard – equipment malfunction Soft - aspects of human communication e.g. tiredness, bias

14. CB1004 Modelling Business Systems 514 Networks and multiple communication systems Structure – how the system components are connected Process – how the components interact Internationally agreed models k/a reference models OSI (open systems interconnection) TCP/IP (Transport control protocol/internet protocol)

15. CB1004 Modelling Business Systems 515 Tanenbaum model (1996) LayerName 5Application 4Transport 3Network 2Data link 1Physical

16. CB1004 Modelling Business Systems 516 Tanenbaum model Defines what each layer has to do to contribute to the system, plus communication between layers and interaction with each layers interface: Physical layer Carries out protocols ensuring data transmitted corresponds to data received Wireless transmission, cellular radio Data link layer Creating groups of data with overall meaning; error detection and correction

17. CB1004 Modelling Business Systems 517 Network layer uses: Routing algorithms to calculate route through the network Congestion control to prevent blocking of data Address reconciliation Accounting for tolls or charges Transport layer Exploits the various routes through the network

18. CB1004 Modelling Business Systems 518 Application layer Includes email, world wide web, multimedia Utilises Ubiquitous software – can be used anywhere on a network hence opens up a new flexibility for business. The power of the information system would be the power of the internet itself Multimedia – no longer restricted to text, opens up virtual reality, simulation etc etc