Techniques for designing a Solution

No matter how skilled you are in using a computer, it will not solve problems for you. Information systems are used as tools to aid problem solving; they do not develop solutions themselves. When we encounter a problem, we embark on some strategy to solve that problem whether we are aware of it or not.

The same goes for the development of any successful information system. It requires careful planning to ensure that it meets the needs of the users and assists the organisation in meeting its goals.

The two most common approaches are the Top Down approach and the Bottom Up approach. The basic difference is the starting point of each method.

Top down (analytical)

Example: Consider a system, the overall goal of which is to provide a means of tracking the financial performance of a company. In order to achieve this goal, the system must be able to track two things: income generated and money spent. These two areas form the next level of the system, and they can be broken down into further subsets, which in turn can be broken down into smaller subsets or tasks.

Example: The top-down technique may be applied to a school student record system. The major function of the system will be to store and maintain accurate student information. The output required could be class lists; students sorted by details such as name and address; students selected by key information such as age. The main function could be broken down into such tasks as adding, deleting, editing and searching for selected information and sorting student records. Each task will require a set of inputs and procedures to complete the task.

This approach is also referred to as a modular approach, and is closely related to the use of data flow diagrams. The major benefit of this approach is that the tasks are broken down into smaller manageable ones, and each can be developed in a manner that allows the system to quickly take shape. Further, the system can easily be broken up into related tasks, and the structure defined so all interdependencies are clearly identified and understood. Because of the significant amount of analysis that this method relies upon, it is often referred to as an analytical approach.

Bottom-up (synthetic)

In the top-down approach, the functions are broken down into smaller tasks, whereas the bottom-up approach starts with the lowest level and builds up a solution. We start by considering the data input and then use this to identify the possible data outputs and the processes required to produce these outputs.

Example: We may wish to analyse the results of a survey. We can easily identify the data input on the survey forms. From the input data, we can identify many possible types of output, for instance bar graphs, or tables. We could also correlate results such as comparing incomes with places of residence on census forms. Once we identify the outputs desired, we can determine the processes needed.

Iterative

Another common method used is the iterative technique. This technique requires the user to produce a quick solution that may be imperfect, and then refine this solution until it meets all the requirements. It produces a number of intermediate solutions, each one progressively closer to a final solution. The aim of this technique is not to produce a perfect solution, but to produce a solution that meets all the constraints.

Example: This technique can be seen operating in most schools when a timetable is developed at the start of a new year. The timetabler will begin with an immense amount of raw data and many constraints that the solution must conform to. The timetabler will first create an initial solution that includes as much of the raw data and constraints as possible. This intermediate solution becomes the input to the next stage and is progressively refined to include more data and constraints until a final working solution is obtained.

Advertisements

Formats and Conventions

Formats are the rules and guidelines to the structure of a document, showing how it will be laid out, and what elements will appear where.

For example, when doing a letter, the fully blocked format is common.

Conventions are the general rules to follow when presenting a document, that is the font sizes and styles.

For example, using all capital letters is considered to be going against convention that dictates that text should be in lowercase.

Formats and conventions should be applied to any product produced. It is very common for organisations to set up their own conventions and standard formats. They may use templates to assist employees in conforming to them. Your school should have a list of any formats and conventions that you are expected to follow.

Example: When producing web sites the following formats and conventions might be considered.

  • Consistency of text, style, size, alignment (horizontal and vertical), colors and background.
  • Use clear readable fonts, generally sans serif
  • Use graphics, movies and sound sparingly
  • Movies should be sharp and short
  • Graphics should be small in bytes and should complement the page
  • Navigation should be clear, easily followed, in a consistent location, and you should use a consistent color scheme
  • Contrast should be used to provide a focal point for the audience
  • Key elements should be consistent and repetitive
  • Elements should be linked through proximity and spacing, related items should be easily identified
  • Page size should be 1-5 screens, split pages that are longer
  • Page size should be 640×460; this is the most common screen size and ensures no vertical scrolling
  • Main/Home/Core page should not take any longer then 15 seconds to load
  • All pages should have author, date modified and email contact
  • Page/File names should be in lowercase and should not contain special characters or spaces

Data

Data may be obtained directly using a primary data source (first hand) or indirectly using a secondary data source (second hand).

Example: An organisation may require data in the form of names and addresses of employees.

The source of the data will be the employees. This data may be acquired using a number of methods, such as direct contact (asking them) or through employment declarations (filled in at the time of employment). The data may be in a number of forms, such as numeric or textual.

data

Data structures are organised collections of data items. For example, the text on this page is organised or structured into paragraphs, sentences and words. It is structured according to the rules of English so that it can communicate meaning to the reader. Computer-based data structures are used to facilitate the processing, as well as the storage and retrieval, of data. A common structure used by computers is tables of records.

Records: most organisations have a table of important data, for example clients, customers, books, products, videos. A table consists of columns and rows. The columns describing what characteristics will be stored about each entity (the field headings) and the rows defining the characteristics of each entity. This table holds a collection of records (the rows).

In structuring a table a number of things must be considered:

Field names – allows easy identification of data items

Field width – sets aside a set number of ‘spaces’ or digits this can also assist with validation, for example, you might set a postcode field to 4 this would ensure that no one entered more then 4 digits.

Field type – the type of data to be stored in that field, for example, character, numeric, date. This also helps to ensure no incorrect data enters the system. If a field was set up as date, only ‘real’ date could be entered. The system would pick up unreal dates such as 30/2/99.

Primary key – ensures data integrity, no duplicate records, each record uniquely identified by a key, such as a membership number or license number.

If data structures are chosen that do not reflect the structure of the input, the meaning of the data can be obscured. For example, if this text were printed as one word per line it would be difficult to extract the meaning, although the data is identical. Each form of output has a particular data structure; a text document would be structured differently from a web page or a presentation file. A spreadsheet would be structured similarly to that of a table, but would be mainly concerned with providing the numeric information required rather then reporting on the collection of records as a database would.

Types of Information Systems

Organisations use a variety of Information systems to produce the information it needs to solve problems. The use of information within organisations is not new, but computer technology has enabled accurate and current information to be created with ease. Organisations are aware that information is a resource that is of strategic and/or commercial importance, and one that computers can adapt and cultivate to their benefit.

Transaction-Processing System (TPS)

Transaction-Processing Systems process data generated by an organisation’s day-to-day transactions or activities.

Examples of TPS’s are pay advice slips, billing systems, invoicing, stock control and order entry systems.

There are two types of TPS:

  1. Batch processing: where data is collected as a batch and processed at a later time, e.g. Bank cheques were usually processed overnight
  2. Online transaction processing: where transactions are processed as they are entered, e.g. buying tickets for a performance

Management Information Systems (MIS)

The purpose of Management Information Systems is to meet the general information needs of all the managers in an organisation. They provide information to the users in a wide range of forms – from simple reports to complex simulations using mathematical modelling.

The primary focus of an MIS is to provide a link for management to the data that is contained within the computer systems of the organisation.

Executive Information Systems (EIS)

Executive Management Systems have the following characteristics:

Provide Information: Information is provided to management of the organisation in a variety of formats and for a number of intended uses.

Provide Analysis Tools: The EIS will enable the data that has been collected in other CBIS to be analysed for planning, commercial or strategic use.

Provide Organisation and/or Resource Assistance: Will enable users of the system to perform their roles in a more efficient manner by providing a range of tools that support decision-making processes.

Decision Support Systems (DSS)

Decision Support Systems (DSS) support managers as they solve semi-structured problems. The emphasis is on how effective the decision is, rather than how efficient the decision making process has been.

DSS tend to break into four major software categories:

Brainstorming software: Where problem solvers record their ideas, view the ideas of others, and comment on others’ ideas in a structured format. The end product is a written record of all the ideas and comments. The software provides decision making support by identifying where and at what level the problem is located.

Consensus Building Software: The software informs the decision-makers of the degree of uniformity in their alternative evaluations. When there is not general agreement, the problem solvers can engage in further discussions. This software seeks a common solution where there is disagreement. The system provides decision-making support by encouraging the selection of the best alternative.

Group Authoring and Outlining Software: Where a problem solver can create an outline of a written report, and each problem solver can contribute independently by writing sections or making suggestions to sections written by others. The written document therefore reflects consistency and agreement as it progresses to its finished form. The system provides decision-making support by enabling problem solvers to implement their solutions.

The virtual office or Office Automation System

The virtual office is not a single computer system, rather it is the combination of a number of communication devices and/or systems that enable effective communication to remote locations. Many of the devices that contribute to the virtual office are computer related, but all are members of an information system.

Any one organisation may not have all of major elements – organisations will select the elements that are of most use to them. They may have one or two of the major elements, or 5 or 6, it will depend upon their individual needs and resources. Elements should be selected on their ability to improve the efficiency of the organisation.

Knowledge Based Systems (KBS) or Expert Systems

The most recent development in CBIS, has been the creation of Knowledge Based Systems (KBS) . Still in its infancy, KBS have the potential to provide systems that allow an organisation to extend its problem solving capabilities. KBS are really a subset of artificial intelligence (AI) and expert systems, and are designed to mimic the human thought processes. A heuristic approach (a rule of thumb or a rule of good guess rather than absolute rules) is used in KBS, and as a result KBS do not guarantee results as absolutely as DSS. Rather, KBS advise on methods to solve a problem, acting as a consultant in the decision-making process. KBS generally consist of a user interface, a knowledge base, an interface engine and a development engine. The knowledge base uses rules to express the logic of the problem that the expert system has been designed to solve, the interface engine uses reasoning (like humans) to process the contents of the knowledge base. The development engine consists of either programming languages or prewritten interface engines called expert system shells.

KBS enable managers to consider more decision alternatives, use a higher level of logic in evaluating the alternatives, have more time for the evaluation and make decisions in a more consistent manner. KBS have major limitations in their inability to apply judgment, intuition and generalisation. The development of Neural networks – highly simplified models of the human nervous system that exhibit such abilities as learning, generalisation and abstraction that enable computer systems to learn human like behaviour – are the major focus in removing the limitations of current KBS.

Information Systems

infosys1

Information system is an academic study of systems with a specific reference to information and the complementary networks of hardware and software that people and organizations use to collect, filter, process, create and also distribute data.

Data is manipulated (processed) to produce something useful known as information. Information is used to solve problems and make decisions so that organisations may meet their goals. An information system consists of people, data, equipment (hardware and software) and procedures.

The two essential elements that information systems deal with are data and information. Information is nothing more than a meaningful way of looking at raw data. Data can include words, numbers, sounds, graphics and video.

We are now living in an age where information and our ability to manage it have become extremely important and is the foundation of this subject. This has lead to phrases such as the “Information age”, “Information is power” and the “Information superhighway”.

To create that all-important information, data is transformed through employing a number of interrelating phases, referred to as the phases of information processing. There are nine clearly delineated phases of processing. Data can be obtained and processed in a multitude of ways.

Acquisition: Data may be acquired from a range of sources from inside or outside the organisation. The data collected could be primary or secondary, for example, from a client order form or from a CD, such as the Census data.

Primary – data that is normally unprocessed in any way and is collected first hand.

Secondary – data that has been processed by others before it enters the system.

Input: This can take a number of forms depending on the type of data and the equipment being used.

Validation may occur during data acquisition or data entry. Validation can check that data is reasonable, with a set range, within a data set, etc. For example, when filling in a Census form, the collector goes through it to ensure all sections are filled in, and when the forms are scanned, the scanner rejects incorrect data (forms). Both these methods aim to ensure accuracy of data. Another common example is the bar code scanner at the supermarket, it beeps and the red light flashes when it can register an item. It is validating that the item exists against a known data set.

Processing: This phase normally involves the use of a range of software types that allow the data to be manipulated, whether that be into a fully blocked letter or a payroll calculating spreadsheet.

Storage: This phase requires the implementation of appropriate storage procedures, including file-naming conventions, saving the location and backup methods.

Retrieval: Where and how the data is saved will effect this phase. For example, if everything is accessed from a tape then it will take more time than if accessed from a CD.

Output: This form could be hardcopy or softcopy, that is printed on paper or displayed on screen. It is expected that to be effective information, the information will have been processed and thus presented using appropriate formats and conventions.

Communication: This could be done electronically, through email etc, or paper based through printed reports, mailed or hand delivered.

Disposal: Files may be deleted or archived (mostly due to legal requirements).

These phases do not necessarily follow each other, or all occur, or occur only once, when solving an information problem.