Unit 1.2
Components of an Information System



Computers enable information to be produced and manipulated very effectively. For example, wide-area networks allow information to be distributed over great distances at high speed. All organisations depend on the creation and use of information. Data must be collected and sorted, calculations and processing earned out and resulting information must be disseminated to a range of people.

The arrival of IT-based information techniques has speeded up the data collection process. Large amounts of data can be processed, analysed and the information generated can be communicated very quickly. Electronic links improve communications and reduce the need for paper, Decision making can be speeded up and an increased confidence in decisions created.


Data processing systems

The first commercial computing systems, developed in the 1950s and 1960s, were data processing systems that replaced the manual clerical procedures that were currently in use. Computers were able to carry out processes such as calculating and sorting more quickly, accurately and consistently than humans.

The first examples of such systems were developed for activities such as the production of the payroll for employees and billing systems. The earliest systems input and stored data on punched cards. Over the years, magnetic media (tape followed by disk) took over the storage role and a range of input media such as OCR, MICR and key-to-disk were used to input the data. Huge, high-speed line printers were used to produce paper outputs: payslips, bills and long lists
of transaction details for internal use on continuous, perforated paper. These data processing functions are still carried out in the most up-to-date systems.

A data processing system is designed to process the data generated by the day-to-day business operations of a company. Examples include systems for accounting, invoicing, stock control and order entry. For example, a clerk processing a customer order needs to know whether the item is in stock, what the price of the item is, what discount, if any, the customer should be given, as well as customer details such as address and credit status.

Data processing systems are, in the main, tools for the operational level of an organisation. Their development over the years has had a major effect on the number and type of jobs at this level. Such a system by itself does not provide the kind of information necessary to help tactical or strategic decisions to be taken by middle or senior management. However, the information needed for such decisions can be produced from the data gathered for these operational systems. Information systems were developed to enable managers to make use of the information.

An example of a data processing system is a payroll system for a large company. Data concerning overtime from time sheets is entered via a keyboard. A program is run that reads the time sheet data and accesses a staff file for necessary data (such as basic salary, tax code) so that pay details can be calculated. Pay slips are printed for distribution to employees and the necessary data is transferred electronically to the appropriate banks to initiate the transfer of funds.

Information systems

An information system is a system that processes data to produce information in such a way that it can be used to help in decision making. In many systems, data processing and information systems operate together at the same time. An example of such would be an airline booking system. Flight bookings are made using an on-line system through which seats can be reserved for passengers. The system produces tickets, and boarding cards as well as various lists. For example, the catering company would need to know the exact dietary requirements of the passengers for a particular flight.

The flight booking system also provides an information system for the customer, travel agent and airline. The airline can find out the percentage of seats sold. Using the on-line system, the customer can gain information on the availability of seats for a range of flights. This can help her to make a decision.

A payroll data processing system could be transformed into an information system by adding reporting facilities to the day-to-day functions of inputting timesheet data and outputting cheques and payslips. The reports could include a summary of the total wage bill, broken down into departments.

In a school or college, a timetabling system that produced summaries of class sizes, staff workload and room utilisation as well as allocating students to classes and printing individual timetables, would be an information system.

 

Management Information Systems

A management information system (MIS) is an information system that aims to provide a manager with all the information needed to make decisions
associated with her job as effectively as possible. Management information systems are a subset of information systems. Like any information system, it converts data into information. The data can come from both internal and external sources. The rapid growth in the use of database systems within organisations has allowed MIS to develop. An MIS is usually based on data from one or more databases.

Management is not an activity that is only performed by people who are called managers. It is carried out at all levels of an organisation: strategic, tactical or operational. Management involves a range of functions: decision making, planning, co-ordinating, controlling, directing and forecasting.

An MIS converts data into information for a manager. The data is usually already held in the computer as a result of data processing activities. It is important that the information is produced to the correct level of detail.

For example, an operations manager of a chocolate factory needs to decide the number and types of bars to be made in a particular week. The following information would help him make this decision:

This information could be created from the data collected as part of the day-to-day operational data processing system.

The sales manager for the same company will require information on products sold rather than products produced. He will need to be able to compare the performances of different members of the sales force. The information will need to be in summary form - perhaps represented graphically.

To make effective use of the information, a manager will need to receive it in an appropriate form and at a suitable level of detail. The amount of detail will usually relate to the level of management using it.


Strategic information

Strategic information is used by senior managers such as directors-and the chief executive in a business or head teacher and governors in a school or directors of a charity. Long-term planning is a key function at this level of management and most decisions made will reflect this. An overview of the operation of the whole organisation is required so that an assessment can be made of how well objectives are being met. Actual costs and profits need to be compared with forecasts for all sections of the business. An MIS can produce projections and predictions based on current data, both internal and external, that relates to the business.

The nature of strategic management means that the information that is required at this level can be very varied both in content and in timing. There will be a need for some regular reporting, but depending on the decision to be made, other, one-off, information maybe needed. External sources will often play a major role at this level. Many organisations are developing Executive Information Systems (EIS) which allow management access to information from wide ranging sources in a variety of forms.

For example, a company that produces and sells ice cream and other associated products has six factories located in different parts of the United Kingdom. The senior management may wish to close down one factory to reduce costs. This would be a strategic decision and would need a wide range of information. An example of internal information would be the increase in labour costs at each factory. External information would include the present site value of each factory.


Tactical Information

Middle managers, typically department heads, regional or functional managers, have roles that are tactical. Such a manager would be responsible for a certain section of a business and would be responsible to a senior manager. She would be likely to have a number of operational managers reporting to her. In an organisation with geographical specialisation, such a manager could be responsible for a sales region, a specific factory or group of shops. In an organisation that specialises functionally, a middle manager could be in charge of training, customer accounting or IT Services.

Much of the information needed by such managers relates directly to the operational performance of the organisation and is used for monitoring and controlling purposes. For example, sales figures for each of the company's sales representatives. Regular reports to assist making tactical decisions are common at this level in a variety of forms: tabular, graphical and pictorial. The information is usually prepared on a routine basis, perhaps weekly or monthly. A factory manager of the ice cream company might consider running an extra shift during the summer months. Such a decision would he a tactical one, based on tactical information.

Exception reports, for example a list of all sales figures which fall below their target level provide tactical level managers with a powerful tool in establishing areas for further investigation. Successful decision making at this level often depends
upon accurate forecasting. (For example, cash flow forecasts.) Modelling the situation with different data can enhance this. Decision Support Systems (DSS) are useful here (see page 000).


Operational information

Operational managers are closely involved at the productive end of the operational. A supervisor may oversee the workforce on a particular production line. He may need to work out rotas and rest breaks, monitor the rate of production, ensure that hold-ups due to machine failure or delay in the arrival of spare parts are minimised and ensure that the quality of the finished product is maintained within acceptable levels.

Consider the role of a manager of a small retail shoe shop that is part of a large national chain. She will need to organise staffing rotas, balance the till at the end of the day, re-order stock, monitor sales on a daily, weekly and monthly basis.

Operational information is needed by such managers to help them in their decision making on a day-to-day level. Nowadays, many operational decisions, such as when to re-order stock are made automatically by the computer software. The re-ordering can itself be initiated automatically. Simple lists and charts will play a major part in operational information. Such a list could be produced by sorting the transaction data that has been processed as part of the normal data processing function.

At the operational level, information is characterised by a high level of detail. For example, in the shoe shop chain, the local shop manager might require a daily, itemised list of all shoes sold, sorted into types, styles and quantities. The regional manager (tactical level) would require a weekly or monthly summary report showing the total sales for each shop in her region. At a strategic level, the marketing manager might wish to forecast sales trends over the next few years.

DEVELOPMENTS WITHIN MIS

As the power of computers has rapidly increased alongside the developments in communications, there has been a growth in the developments of specialised management information systems for different levels of users. Although these are becoming popular, they are by no means universally used in organisations and many problems still remain with their implementation.


DECISION SUPPORT SYSTEMS

Systems called Decision Support Systems (DSS) help decision-making but they do not themselves make decisions. They are particularly valuable when making one-off unstructured decisions that cannot by their nature be produced on a routine basis from an information system. DSS are used at the strategic or tactical management levels. They enable a manager to explore a range of alternatives under a variety of conditions, For example, a manager may wish to know the effects on profits if sales increase by 5 to 15 per cent and costs increase by 5 to 12 per cent

DSS are hands-on, interactive systems. They need to be user friendly and easy to use so that managers can use them with confidence whenever needed. Examples of DSS include spreadsheets with their what-if capacity for modelling and testing out different scenarios, and statistical packages.

A decision support system is a system designed to help someone reach a decision by summarising all the available relevant information. Some of this information may be held in the company's database, and some may be external to the company. External information could include current interest rates, the price of oil, population trends, or details of new competitors starting up in the area.

Decision support systems often include query languages to enable managers to make spontaneous requests from databases, spreadsheet models that enable what if calculations to be made, and graphics to provide a clear representation of the available information.


Executive information systems

Most management information systems will provide summary, statistical information suitable for senior management. Often, however, such summarising hides crucial detail, The need for such detail would be impossible to predict as it depends on specific circumstances. This lack of appropriate detail could result in incorrect decisions.

Executive Information Systems (EIS) (also known as Executive Support Systems (ESS)) provide aggregated information for senior managers. The manager can display the information in more detail by clicking on hot spots. Such a system would bring together information from a range of internal and external sources.

For example, a senior manager is reviewing company expenditure over the past year, comparing with the estimated budget. This information is displayed in a graphical form. She then notices that one department is well over budget, and decides to investigate further. A click of the mouse on the appropriate figure results in the details of the budget and expenditure of the department in question is displayed. It appears that the overspend is greatest in the raw materials expenditure, so our manager clicks on this figure to reveal that prices are as estimated but the department has produced more raw materials than planned. The manager can investigate sales and stock levels to find out whether these extra purchases were necessary.

An ETS could also provide access to newspaper articles, economic indicators and are usually linked to e-mail systems. An EJS is a simple, easy to use interface, which sit on top of huge databases. The manager is able to view a high level, overall summary of data and then drill down' by selecting a particular figure or hot spot, and see more detailed displayed. This drilling down can be continued to greater levels of detail.

A key feature of an EIS would be the quality of its presentation. Such systems are designed to be used by managers at the highest level of an organisation. Many such people are unused to using IT and are not prepared to invest much time into learning to use complex and unfriendly systems.
Currently there is a huge growth in the development of Intranets within organisations. An Intranet uses the same browser software that is used to access the Internet, such as Netscape or Microsoft Explorer. The information available on an Intranet is internal to the organisation. A well-managed Intranet can provide a very useful tool for sharing information,


Expert systems

An expert system is a computer program that tries to emulate human reasoning. It does this by combining the knowledge of human experts on a given subject, and then following rules that it has been given to draw inferences. To use the system, the user sits at a terminal and answers questions posed by the computer. The program eventually reaches a diagnosis or decision and will also tell the user how it has reached a particular conclusion.

Expert systems are also called knowledge-based systems and are able to store and manipulate knowledge so that they can help a user to solve a problem or make a decision.

An expert system is limited to a specific area of expertise such as the causes of a car's failure to start. It is typically rule based although it is able to work with uncertain or incomplete data. An expert system does not replace a human but delivers advice for a course of action based on the data given. This advice mimics the advice that the actual expert or experts who provided the knowledge for the system would have made. An expert system is able to explain its reasoning to the user.

An expert system is made up of a knowledge base that contains the facts and rules provided by a human expert; a means of applying that knowledge (usually called an inference engine') and a means of communicating with the user (the human-computer interface').

The knowledge base will store knowledge in different forms, namely FACTS and RULES. For example:

THE STANDARD CAR RENTAL IS �30 PER DAY - FACT
IF THE CAR IS A LUXURY MODEL, ADD �10 PER DAY - RULE
IF THE CAR IS HIRED FOR THREE DAYS DEDUCT 20 PER CENT - RULE
IF THE CAR IS HIRED FOR SEVEN DAYS DEDUCT 30 PER CENT - RULE
IF THE DRIVER HAS A LOYALTY CARD DEDUCT ANOTHER 10 PER CENT - RULE
THE SHOWROOM IS OPEN SEVEN DAYS A WEEK - FACT

Knowledge like this can be stored in a knowledge base, and the expert system should then be able to make deductions.
If we supply the information about when Mrs Miggins wishes to hire a car, the expert system should guide us through a series of relevant questions and work out the charge.

In practice, such as in a system that calculates the level of income support for an individual, there may be hundreds or thousands of facts and rules. When the program (the inference engine) runs, it does not simply start at the first rule and then run through them all in a axed order. Instead it makes deductions as it goes along, finding out what else it needs to know before providing an answer.

USES OF EXPERT SYSTEMS

Expert systems are best suited to where a well- defined set of rules exists or can be written down. Expert systems have been used in such fields as medical diagnosis, fault diagnosis in a steel rolling mill, classifying, debugging, prediction, planning, geological prospecting, processing Social Security claims and quantity surveying.


Developing an expert system, by prototyping

The person who carries out the tasks of defining a problem, constructing a suitable system, acquiring the knowledge to go into the system and developing the system is called a knowledge engineer. His job is similar to that of a systems analyst. Acquiring the rules and facts from an expert is not a simple task. Many rules' that an expert uses to make decisions are very complex and not always consciously acknowledged. There are always many exceptions or special cases that need to be included.

Expert systems are nearly always built using prototyping, whereby a trial model is developed so that users can try it out and evaluate it.

Expert systems allow expertise that is in short supply to be more widely shared. When particular experts are no longer available, their expertise is still available. An expert system that is based on the knowledge of a number of experts could provide better advice than an individual expert. The demand for human experts might decrease. For example, an expert system that dealt with all the legal aspects of house conveyancing might make it unnecessary for house buyers to employ a solicitor.

There are a number of dangers associated with the use of expert systems. If the knowledge engineer does
not do an adequate job, the advice given by the expert system could be inaccurate and inappropriate. If the advice given by the system is used without any interpretation, it could be wrong.
A number of experts systems have been developed in the field of law to enable the user to pose legal problems or check the legality of a possible decision or action, The knowledge base of legal facts and rules from Acts of Parliament and case law is built up by consulting a number of law practitioners


Success or failure of MIS

In spite of many technical advances and the investment of huge amounts of money, time and effort, many management information systems have not fulfilled their promise and have failed to provide the management with the information that they need. Just as with any information processing system, careful planning is needed if it is to he successful.

It is vital that the management is involved with the design of the system, They are to be the users, and it is therefore crucial that any system meets their real needs. However, for this involvement to be useful and realistic, the management will need to have an up to date knowledge of current information technology systems and their capabilities. They will need to be able to make informed decisions, and not be blinded by the IT experts' knowledge and use of jargon. Some form of training may be necessary. An inadequate knowledge of the capabilities of current technology may result in management making inappropriate or excessive demands from the system. When the system inevitably fails to meet their high expectations they will be disillusioned and may not then use the system. It is important to understand that IT does not always bring benefits.
It is equally important that the IT experts spend adequate time getting to know the information needs of the managers. This can only be achieved once a thorough understanding of the organisation has been achieved and a detailed analysis made of the system. Systems development should be the result of a true partnership between management and IT professionals. Managers do not always know what information they need and IT specialists do not always know enough about the process of management and the business in question.


Many management information systems have failed to provide adequate information as too much emphasis has been placed on the lower level data processing applications. A poor system will be produced if there is too much emphasis on the computer system and inadequate attention given to the whole system and the data flow throughout the organisation. The system should be designed around the information needs of the managers rather than be based upon what the computer can easily produce.

Inadequate teamwork and a lack of professional standards can lead to unmet deadlines and a system that does not function as was intended.

Not all MIS systems are implemented successfully. Factors influencing success or failure include:

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