1. IT04:Expert Systems Chapter42 Also in Doyle ch11

2. Executive information systems  Help higher management spot a problem, opportunity or trend.  Enable managers to access increasingly detailed levels of data in order to try and analyse problems or opportunities.  Need to be user-friendly and capable of producing various forms of output such as exception reports, graphs and charts.

3. Information flow Formal methods of spreading information around an organisation include:  Computerised information systems allow users to query databases company-wide  Internal data - transaction processing systems  External data - Dun and Bradstreet  Software packages such as Lotus Notes allows people to work on the same document / shared folders  E-mail - transmits correspondence and files  Company-wide Intranets - networks within the organisation

4. Expert systems (Knowledge- based systems) Computer programs that attempt to replicate the performance of a human expert at some specialised reasoning task. Able to store and manipulate knowledge so a user can solve a problem or make a decision.  Limited to a specific domain (area of expertise);  Typically rule-based;  Can reason with uncertain data (the user can respond “don’t know” to a question);  Delivers advice;  Explains its reasoning to the user;

5. An Expert System has the following constituents:  The ‘knowledge base’ containing the facts and rules;  The ‘inference engine’ the computer program;  The ‘human-computer interface’ to communicate with the user.

6. Uses of expert systems  Medical diagnosis  Fault diagnosis of all kinds gas boilers, computers, power stations, engines  Geological surveys to find oil and mineral deposits  Financial services to predict stock market movement  Social services to calculate the benefits due to claimants  Industrial uses such as ELSIE in the construction industry

7. Benefits of expert systems Some of the organisational benefits are:  Can do some tasks much faster than a human e.g. cost calculations for a construction project  Reduces downtime of expensive equipment when an expert system can diagnose the fault  Error rate in successful systems often very low may be lower than that of a human  Recommendations consistent and impartial given the same facts

8. Benefits of expert systems (cont) Further organisational benefits are:  Can capture scarce expertise e.g. of professional who leaves/retires, and can be used at places where human expert is not available  Repository for organisational knowledge the combined knowledge of all the qualified experts in an organisation  Useful for training employees

9. Limitations of expert systems  Can make mistakes, just as humans do - even a low error rate e.g. in the diagnosis of a disease, may create mistrust  Expert systems do not ‘learn from their mistakes’ - new knowledge has to be entered into the knowledge base as it becomes available  Difficult to acquire all the required knowledge - from the human experts in order to build the expert system  Use can result in decline in skill level - of some of the people using the systems  Over-reliance may stifle creative thinking - and lead to advice delivered being slavishly followed

10. Homework Read Chapter 11 Doyle Using an essay style and remembering that the quality of writing within essay questions is assessed at A2 level. Answer the question 3 on page 181 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Hand in date theory lesson (your second IT class of next week - Thursday 11 October 2001).