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IMS9001 - Systems Analysis and Design

IMS9001 - Systems Analysis and Design. Communication and documentation during systems development. Communication and documentation. Information systems documentation: System specifications: e.g. requirements, design, software; data dictionary/ repository, manuals , etc. Written reports

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IMS9001 - Systems Analysis and Design

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  1. IMS9001 - Systems Analysis and Design Communication and documentation during systems development

  2. Communication and documentation • Information systems documentation: • System specifications: e.g. requirements, design, software; data dictionary/ repository, manuals, etc. • Written reports • Presentations See additional notes on the unit web page included with the lecture notes for week 11

  3. What is documentation? • Not necessarily a piece of paper. • Any permanent medium used to communicate to other people can be classed as documentation • Product and documentation should be developed at the same time • DOCUMENTATION IS PART OF THE PRODUCT Documentation is communication: • the objective is to: • create a specific effect • on particular readers • who want specific information, • have particular characteristics and • will read under particular circumstances.

  4. Information Systems Documentation • User Manual • Systems Manual • Data Manual • Program Specification Manual • Operations Manual

  5. User manual • Purpose: • a contractual obligation • a marketing tool • a training tool • a reference for non-technical people • a memory in case key staff leave • Contents: • what the system is about (narrative); • how to use the hardware how to carry out tasks - details of manual procedures involved; how to enter data, produce output, interpret output; • how to correct mistakes • how to solve typical problems; • how to ensure security; • how to perform backup and recovery.

  6. Systems manual • Purpose: • to enable technical staff to understand the system so that they can: • modify the system • evaluate the system’s behaviour • fix errors in the system • Contents: • overview of the system • descriptions of all components • system specifications • controls, errors, audit trails.

  7. Data Manual • enables (technically-oriented) developers and maintainers to: • understand what data is used and where. • identify the effects of changes relating to data. • Contents: • Files - schemas, sub-schemas, file layouts. • Inputs/Outputs - reports; inputs • Data Elements • Data Analysis - logical and physical data model

  8. Program specification manual • Purpose: • to support communication between analyst/designer and programmer; • to describe in detail what the program does • for initial development; • for maintenance. • Contents: • design specification (narrative describing the purpose and general functions of the program), • listing of each program (for maintenance purposes), • layouts of files or database area used, • layouts of screens and reports, • test plan, test data, test conditions, test results

  9. Operations manual • Purpose: Large scale systems may need operations support. If so, a separate operations manual is needed to instruct operations staff in operating and controlling the new system. • Contents: • system overview (purpose/functions of the system) • processing flow • system start-up/shut-down • restart and recovery procedures • security/backup procedures • tape/disk library instructions • user contacts and procedures • priority of jobs • report distribution information

  10. Operations Manual • Planning large-scale system operations: • Large scale systems require: • breakdown of the work into jobs (individual programs) • scheduling of these jobs into a sequence • For each job: • narrative description of the job • job flowchart • job schedule requirements • job set up instructions • input control procedures • operator's instructions • job rerun/recovery procedures • data control instructions • report distribution instructions

  11. Good Documentation For a user, the system is only as good as the documentation describing it Good documentation: • reduces the need to refer problems to system developers • overcomes users’ fears of equipment and software • ensures successful first encounters with a system • enables users to find what they want and understand it when they find it • is accurate and complete • is written for the intended audience and purpose • has good reference aids (table of contents, thorough index, cross-referencing)

  12. Planning your documentation • Audience - sets the tone, style, language and emphasis • level of computer sophistication • background, training, or education • attitude towards your message • cultural background • Purpose - why is the documentation necessary? • identifies the content • indicates the level of detail required • Medium • paper-based manuals and reference cards • on-line documentation • aural and visual training materials

  13. Audience • Type of documentation Audience • User Manual users - new, intermediate, experienced • System Manual client, maintenance team • Data Manual (Data Dictionary) developers, maintenance team • Program Manual developers, maintenance team • Operations Manual operators, technical staff

  14. Document organisation • Principles • Make the organisation of material apparent to readers • Tell them what you are going to tell them before you tell them • Organise the document in ways expected by readers: • chronological order • most important to least important • order of need • order of difficulty • question / answer order • compare/ contrast order • alphabetical order

  15. Documentation organisation • Chunking - the rule of seven • Labelling - briefly describe upcoming information • Relevance - put related information together • Consistency • Hierarchy of chunking and labelling - Chapters, Sections, Topics • Integrated graphics • Accessible detail - access routes to different levels of detail

  16. Choose appropriate media • Manuals • Most common ... not good for trivial problems. • Brochures • Main capabilities are highlighted ... emphasises simplicity and elegance, not the detail of manuals. 4 - 8 pages fully describing the system. • Quick reference guides • 90% of the time 90% of the needs of 90% of the readers can be met by a simple summary card. • On-line help • Ideal reminders ... useful as an aid for experienced user BUT are not a replacement for manuals

  17. Online vs paper-based documentation • Online easier to distribute and maintain • Printing costs reduced • Online enables different search paths to the same information • Easier for user to become disoriented • Online documentation must be written differently • Online documentation must be consistent with paper-based documentation

  18. Reference Aids • Information is often inaccessible • Use: • Glossaries • Indexes (very important) • Contents page • Others • Numbering systems • Page, Sections, paragraphs, items • Section dividers - tabbed card, coloured pages, • Section/chapter summaries

  19. Colour and graphics • Use a minimum number of colours, and be consistent and familiar (eg. red for hot) in your use of colour codes • Avoid putting colours from extreme ends of the spectrum together .. makes it hard to perceive a straight line • Don't rely on colour alone to discriminate between items • Graphics can make a document more effective: • points in a text can be emphasised • can increase reader's interest • can replace, clarify or simplify the text

  20. Layout and Pagination • Layout: • Be consistent in your layout • Use type size (at least 4 points different) or bolding to indicate relative importance or weight • Page: • Use a page size suited to the environment that the document is going to be used in • Make sure page numbering is clear

  21. Planning a Cost-time Schedule • Why? - Often documentation is forgotten, ignored or dismissed as not being important. • Aim - to develop an estimate of the time required for documentation DURING development .. not a trivial task. • Time vs Cost - be realistic about your estimates .. • Time saved in the documentation task will be wasted many times over explaining things not included or not clearly described in the documentation provided.

  22. The Documentation Process Specify the document Draft and edit the document Not OK Review the document OK Maintain the document Publish the document

  23. Effectivedocumentationcheck list • Objective clearly stated • Target audience identified • Consistent approach used (wording, structure, layout) - templates help • The principles of documentation organisation and development have been followed • Maintenance process in place • Put yourself in the users’ position - can you easily find what you’re looking for?

  24. Definitions of Quality • Degree of excellence (Oxford) • Fitness for purpose (AS1057) • includes quality of design, the degree of conformance to design, and it may include such factors as economic or perceived values • Ability to satisfy stated/implied needs (ISO8402) • Conformance to requirements (Crosby, Horch)

  25. Determining Quality .. • when having a meal in a restaurant • when purchasing a car • when buying a computer The requirements vary immensely, and some of the success measures are very hard to quantify... Quality means different things to different people .. and it varies in different situations

  26. Information systems: quality issues The system: • does not meet the client’s business or processing needs • does not support the client’s working methods • is unstable and unreliable • does not improve productivity • is difficult to use or requires excessive training to use • is expensive to maintain

  27. Information systems: quality issues The system: • is incomplete • is expensive to operate • has a short life span • is delivered late • costs more than budget • cannot grow with the organisation • does not produce a return on investment

  28. Error detection in systems • “Effort spent on software maintenance is greater than that spent on software development.” • “An error is typically 100 times more expensive to correct in the maintenance phase on large projects, than in the requirements phase.” Boehm, B. (1981) Software Engineering Economics

  29. Error Detection • * The cost of detecting and correcting errors rises greatly during • the systems development cycle. $ Initiation Analysis Design Implementation • In addition to this is the cost to the organisation of having an incorrect system

  30. Quality Costs The tip of the Iceberg Obvious upfront costs to the organisation Review, Inspection, Re-do, The hidden costs of not having quality systems User complaints, Downtime, Loss of sales, Re-testing, Re-documenting, Re-training, Overtime, Customer complaints, Financial losses, Employee turnover

  31. Quality dimensions • Correctness - Does it accurately do what is intended? • Reliability - Does it do it right every time? • Efficiency- Does it run as well as it could? • Integrity - Is it precise and unambiguous? • Usability - Is it easy to use?

  32. Quality dimensions • Maintainability - Is it easy to fix? • Testability - Is correctness easy to check and verify? • Flexibility - Is it easy to adapt and extend? • Portability - Can it be easily converted? • Reusability - Does it consist of general purpose modules? • Interoperability - Will it integrate easily with other systems?

  33. The Quality Process • The quality process involves the functions of: • Quality control - monitoring a process and eliminating causes of unsatisfactory performance • Quality assurance - planning and controlling functions required to ensure a quality product or process

  34. Implementing a Quality System • Quality must start at the top - Executive sponsorship is vital. • Everyone must be involved and motivated to realise that they have a responsibility towards the final product, its use, and its quality. • Improve job processes by using standards, and preparing better documentation (using project control methodologies). • Use a Quality Assurance group. • Use technical reviews.

  35. Standards • Levels of standards • Industry / National / International • Organisational • Industry • Capability Maturity Model (Humphrey 1989) See Whittten et al (2001) pp 76-77 • National / International • Standards Australia (AS 3563) • International Standards Organisation (ISO 9000) • Organisational • The organisation may adopt or tailor industry, national or international standards.

  36. Standards • Standards can be of varying levels of enforcement and types which will depend on the organisation and project variables. For example : • mandatory practice: must be adhered to • advisable practice: can be breached with good reason • in the form of a checklist, template, or form.

  37. Standards - Examples • Document template (form, e.g. template for these slides) • Acceptance test sign off form (form) • Screen standards (standard - mandatory practice) • Unit test process (standard - mandatory practice) • COBOL II standards (standard - mandatory practice) • Post implementation review procedure (advisory practice) Note: different organisations and projects will have different views about whether a standard is mandatory or advisable.

  38. Quality reviews • Reviews are used in the quality control and quality assurance functions. There are two main forms of review: • Quality Assurance: • management reviews • Quality Control • technical reviews

  39. Management or Project Review • Management must check the baseline for a deliverable to see that it meets the quality assurance requirements. • This may involve simply noting that a technical review has passed a particular deliverable. The manager can then be assured of quality(given that the manager has actively taken part in the development of the quality system) • The manager can then alter the project plan if necessary to allow for delays or early completion.

  40. TechnicalReviews • A technical review is a structured meeting where a piece of work, which has previously been distributed to participants, is checked for errors, omissions, and conformance to standards. • All deliverables need review, otherwise how do you control quality? • The review is part of quality control and must produce a report so that the quality assurance function can be satisfied. • The report may be a checklist which indicates that the deliverable passes/fails the quality requirements for that type of deliverable. • This report is part of the baseline for the deliverable.

  41. Technical Reviews • A technical review: • is a formal meeting of a project team which is guided by an agenda and standards • allows input from many people • produces a report which is made public • requires committed participants to be responsible and accountable for their work • is educational as it clarifies standards, and highlights strengths and weaknesses of the team’s skills and knowledge • expects all participants to be responsible for the resulting quality of the artefact

  42. Technical Review Roles • review member • Know the review process • Be positive and supportive • Interested in improving the quality of the deliverable and the review process • review leader • Secure agreement on objectives and standards • Encourage input from all participants, and politely silence overly talkative participants • Facilitate agreement to ensure action on the deliverable • scribe • Record all issues clearly, accurately, and unambiguously. If not sure of a particular issue, seek clarification

  43. Project Management Quality in Systems Development(must be embedded in the process) Analysts Role Initiation Analysis Design Implementation Documentation Review Maintenance Ethics Quality

  44. References • WHITTEN, J.L., BENTLEY, L.D. and DITTMAN, K.C. (2001) 5th ed., Systems Analysis and Design Methods, Irwin/McGraw-HilI, New York, NY. Chapters 5, 8 • HOFFER, J.A., GEORGE, J.F. and VALACICH (2005) Modern Systems Analysis and Design, (4th edition), Pearson Education Inc., Upper Saddle River, New Jersey, USA.Appendix 1 • ANDERSON, P.V. (1995). Technical writing: A reader-centred approach, 3rd ed. Harcourt, Brace & Co., Fort Worth. • BROCKMAN, J. R. (1990). Writing better computer user documentation - From paper to hypertext. John Wiley and Sons, Inc., New York.

  45. References (2) Abel,D.E. and Rout, T.P. (1993) Defining and Specifying the Quality Attributes of Software Products The Australian Computer Journal 25:3 pp 105 - 112 (particularly pp 105 - 108) Dahlbom, B. and Mathiassen, L.(1993). Computers in Context: The Philosophy and Practice of Systems Design. Cambridge, Mass.: NCC Blackwell. (particularly pp 135 - 157) Elliot, S. (1993) Management of Quality in Computing Systems Education, Journal of Systems Management, September 1993 pp 6-11, 41-42 (particularly pp 6-8)

  46. References (3) Perry, W.E. (1992) Quality Concerns in Software Development. The Challenge is Consistency. Information Systems Journal 9:2 pp 48 - 52 Standards Association of Australia (1991). Australian Standard 3563.1 -1991: Software Quality Management System. Part 1 Requirements Standards Association of Australia (1991). Australian Standard 3563.2 -1991: Software Quality Management System. Part 2 Implementation Guide

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