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IMS9001 - Systems Analysis and Design

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Any permanent medium used to communicate to other people can be classed as documentation ... overcomes users' fears of equipment and software ... – PowerPoint PPT presentation

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Title: IMS9001 - Systems Analysis and Design


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 systems 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
Effective documentation check 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 youre 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 clients business or processing
    needs
  • does not support the clients 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
Technical Reviews
  • 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 teams
    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
Quality in Systems Development (must be embedded
in the process)
Analysts Role
Initiation
Analysis
Design
Implementation
Documentation
Review
Maintenance
Quality
Ethics
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 253 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 92 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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