THE UNIVERSITY OF TEXAS AT AUSTIN
SCHOOL OF INFORMATION


LIS 387.5
SYSTEMS ANALYSIS AND EVALUATION
R. E. Wyllys

Elements of a System and Their Attributes


How to Use This Checklist

What follows is essentially a checklist of elements of systems and the attributes that these elements may have. Most systems have all of the seven major elements, but not all the attributes are necessarily relevant to every system.

This checklist has been prepared for the use of people engaged in the kind of careful analysis of systems, existing or planned, that is implied by the label "systems analysis." As a systems analyst works his or her way through the many aspects of a typical system that is being studied (i.e., analyzed and/or designed), the analyst can use the attributes in the checklist as reminders of questions that need to be asked about the aspects under study.

Types of Elements

Data
Equipment
Personnel
Data Vehicles
Information Stores
Procedures and Programming
Training

DATA: The ingredients of the information that the system uses, processes, and/or produces

Attributes to be Considered:

Unambiguous name: Does each type of data have an unambiguous name within the system?

Relevance to system tasks: To which task(s) is each type of data relevant? is the type of data under consideration relevant to only one task or to two or tasks?

Grain: How narrowly defined, i.e., how specific, is the type of data? E.g., volume number only? volume number and issue number? all books? or just out-of-print books?

Source: What is the source of this type of data? what is the reliability of the source? what is the authenticity of the source?

Processing needed

Destination

Logical relationships, if any: E.g., have both the invoice for the book and the physical book arrived?

Format

Accuracy required: Should this type of data be rounded off to 2 decimal places? Does this type of data require double-precision numerical storage?

Cost

PERSONNEL: Users and operators

Attributes to be Considered:

Functions performed by humans: What functions are performed by humans? should be performed by humans?

Human-decision points: stated vs. actual

Nature of human decisions: Could some of the decisions be made programmatically? Could some of the decisions be made by lower-level staff members?

Authority and information links with other personnel, both formal and informal

Extra-system responsibilities of staff members: committees assigned to? community involvement?

Attitudes toward system and fellow workers, especially toward fellow workers as grouped by departments or other administrative units

Reliability

Turnover

EQUIPMENT: Machinery and other physical equipment

Attributes to be Considered:

Functions performed by machines: What functions are performed by machines? should be performed by machines?

Machine-decision points

Data-storage size

Data input and output rates

Format requirements

Compatibility

Reliability: includes MTBF (mean time between failures), preventive maintenance, backup alternatives, recovery from breakdown)

Modifiability

Physical requirements: light, power supply, weight, size, noise, air-conditioning (temperature and humidity) needs

Location, and provision for possible need to move equipment in future

Future availability of this type of equipment? of equipment performing the same function(s)?

Interface with users and/or operators

Cost: lease, purchase, maintenance (including comparison of the costs of maintenance on purchased equipment vs. the costs of leasing)

Warranties and maintenance arrangements

Security (against accidental and/or willful damage)

DATA VEHICLES: Databases, files, etc.

Attributes to be Considered:

Note: Attributes in this category need to be checked against those of personnel and equipment, since data vehicles share many attributes with those categories.

Degree of aggregation: how many items are handled together?

Format (for both human and machine use): machine coding; human coding (e.g., maps, charts, tables, prose)

Timeliness: how up-to-date must the data be? are only current data desired? or current data plus historical data (e.g., to show trends)?

Selection criteria: all data? summary data? exceptions only? how filtered?

Initiation or access: routine? when and as scheduled? as accumulated? on demand only? who initiates access?

Transduction: mechanism(s) involved in changing the form of data (microcomputer, computer printer, typewriter, terminal, copier, camera, etc.)

Correctness: what are the chances for error? how can errors be detected and corrected? how much error is tolerable?

Cost: physical costs of vehicle? costs of preparing data in vehicle?

Appropriateness of data vehicle to data items?

Retention and security

Source, handler(s), and destination

Relation to other data vehicles

INFORMATION STORES: Disk drives, book collections, World-Wide Web sites, tape cartridges, etc.

Attributes to be Considered:

Size, measured in various ways

Input and output rates desired and/or expected

Growth rate expected

Logical format(s) used

Physical format(s) used

Equipment needed for storage

Equipment needed for input and output

Location

Permanence: what happens if lost? security measures?

Accessibility and privacy considerations

Importance or value (cost)

Replacement and/or backup

PROCEDURES AND PROGRAMMING

Attributes to be Considered:

Interpret functions in terms of specific sequences of tasks to be performed by

Detail procedures for personnel in terms of

Detailed procedures for use of equipment (e.g., specifications for computer programs) in terms of

TRAINING: System staff and system users

Attributes to be Considered:

Definitions of tasks in terms of

Definition of externally acquired skills and knowledge (e.g., qualifications for being hired for the task)

Definition of skills and knowledge to be provided though internal training

Quantities of training needed, as an effect of turnover and of system rate of change

Possibilities of cross-training or re-training of present skills

Procedures for providing training, including staff needed and equipment needed

Training to be provided by manufacturers of equipment or vendors of software systems


Go to Guide to Course Materials for LIS 387.5


Last revised 1998 September 27