|
The system development cycle is driven by the realization
that there are deficiencies
in the system and these problems need to be addressed. A problem
is a gap (variance) between
expectation and reality; variance is large enough that it falls outside
defined tolerance limits, and therefore is worth the
effort/resources/cost needed to be expended
to fix it.
Maintenance programming: on an existing system
Development programming: building a new or replacement system
If the development cycle is driven by the detection of problems,
how do we detect
them? When we observe:
- lack of relevancy
- lack of completeness
- lack of correctness (accuracy)
- lack of security
- lack of timeliness
- lack of economy
- lack of efficiency
- lack of reliability
- lack of usability
throughput: number of error-free transactions per unit of time.
How do we observe these things?
- users may tell us (complaints)
- take surveys (e.g., questionnaires)
- managers may tell us (complaints)
- audits by outsiders
- we can ask (scouting)
- lower sales, loss of revenue
- continuous measurement of variances (TQM approach)
The purpose of the Initial Investigation is to make a
recommendation:
- Take no action. (not a valid problem)
- Provide training/instruction/information to
the end user to resolve the problem.
- Defer action to later. (adding an enhancement rather
than fixing a deficiency)
- Do Maintenance to correct minor problem.
- Consider major modification or system replacement.
A systems analyst must be able to handle project initiation, determine
project feasibility and project scheduling, and manage activities and
systems analysis team members.
Feasibility study: is the proposed project worth doing?
possible to do?
- economic feasibility (cost-benefit analysis) (tangible
economic benefit)
- technical feasibility
- operational/social feasibility
A feasibility study assesses the economic, technical, and operational
merits of the proposed project. A project is economically feasible if
costs do not overshadow benefits. A project is technically feasible
if the technology is available and capable of meeting users' requests.
A project is operationally feasible if the proposed system will operate
and be used once it is installed.
Important criteria for project selection are:
- that the requested project be backed by management
- that it be timed appropriately for commitment of resources (adequate
time frame)
- that it moves the business toward attainment of its goals
- that it is practicable (adequate resources on the part of the
analyst and the organization)
- that it is important enough to be considered over other projects
(worthiness of the project)
What are the objectives of the proposed project?
Acceptable objectives include
- reduce errors/improve accuracy
- reduce costs
- integrate subsystems: reduce complexity, streamline processes,
combine processes
- shorten time requirements (speed up processes)
- reduce redundancy in storage, output
- improve customer service
- automate manual processes in support of the above
Unacceptable objectives include
- Ego-related (personal or organizational ego)
- To gain power
- To gain respect, admiration
- "Because it's Cool!"
- Automation for automation's sake alone
|