Human Factors
Todd Bacastow
Geography 468
Spatial Systems
• Key human factors in spatial systems
– Gender (the court is still out)
– Spatial cognition
• Declarative
• Procedural
• Configurational
– Spatial visualization
•
•
•
•
Manipulation
Rotate
Move
Transform
– Spatial orientation (imagination)
Spatial Systems
– Spatial relations
•
•
•
•
•
Patterns
Shape
Layout
Hierarchy
Linkage
– Map reading aptitude
– Human spatial information processing
• Perception
• Integration
• Utilization
– Mental models & problem solving
– Computer aptitude
– Need/Motivation
Output Design Guidelines
1. Outputs should be simple to read and interpret.
–
–
–
–
–
–
–
–
–
–
15-4
Include a title.
Date and time stamp.
Include sections and headings to segment information.
Clearly label all fields and columns.
Include legends for all abbreviations.
Include only required information. Online provide methods to
expand and contract information.
Report information in format that does not have to be manually
edited.
Information should be balanced across the page or screen.
Provide for easy navigation.
Avoid computer jargon and error messages.
Output Design Guidelines (cont.)
2. The timing of outputs is important.
– This can affect how the output is designed an
implemented
3. The distribution of (or access to) outputs must be
sufficient to assist all relevant users.
– The choice of implementation method affects
distribution
4. Outputs must be acceptable to the system users
who will receive them.
– Systems analyst must understand how the recipient plans
to use the output
15-5
Output Design Process
1. Identify system outputs and review logical
requirements.
2. Specify physical output requirements.
3. As necessary, design any preprinted forms.
4. Design, validate and test outputs using some
combination of:
1. Layout tools (e.g., hand sketches, spacing charts, or CASE
tools.
2. Prototyping tools (e.g., spreadsheet, PC DBMS, 4GL)
3. Code generating tools (e.g., report writer)
15-6
Screen Output Design Principles
Screen Design
Consideration
Design Guidelines
Size
The designer should consider the “lowest common denominator.” The default
window size should be less than or equal to the worst resolution display in the user
community.
Scrolling
On-line outputs have the advantage of not being limited by the physical page. This
can also be a disadvantage if important information such as column headings scrolls
off the screen. If possible, freeze important headings at the top of a screen.
Navigation
Users should always have a sense of where they are in a network of on-line
screens. Users also require the ability to navigate between screens.
Partitioning
In Windows, zones are forms within forms. On the Internet, frames are pages within
pages.
Information
Hiding
On-line applications offer capabilities to hide information until it is either needed or
becomes important. Techniques include drill-down and pop-up dialogue boxes.
Highlighting
Highlighting can call users’ attention to erroneous data, exception data, or specific
problems. Highlighting can also be a distraction if misused.
Printing
Always provide users the option to print a permanent copy of the report.
15-7
Data Capture and Data Entry
Data capture – the identification and acquisition of
new data (at its source).
– Source documents – forms used to record business
transactions in terms of data that describe those
transactions.
Data entry – the process of translating the source data
or document (above) into a computer readable format.
16-8
Data Processing
Data processing is all processing that occurs on the data
after it is input from a machine readable form.
– In batch processing, the entered data is collected into files
called batches and processed as a complete batch.
– In on-line processing, the captured data is processed
immediately
– In remote batch processing, data is entered and edited online, but collected into batches for subsequent processing.
16-9
Input Implementation Methods
•
•
•
•
•
•
Keyboard
Mouse
Touch Screen
Point-of-event terminals
Sound and speech
Automatic data capture
– Optical mark recognition (OMR)
• Bar codes
–
–
–
–
–
16-10
Optical character recognition (OCR)
Magnetic Ink
Electromagnetic transmission
Smart cards
Biometric
Input Design Guidelines
• Capture only variable data.
– Not data that can be looked up.
• Do not capture data that can
calculated or stored in computer
programs as constants.
– Distance, etc.
• Use codes for appropriate
attributes.
16-11
Source Document / Form Design Guidelines
• Include instructions for completing
the form.
• Minimize the amount of
handwriting.
• Data to be entered (keyed) should
be sequenced top-to-bottom and
left-to-right.
• When possible use designs based on
known metaphors.
16-12
Bad Flow in a Form
16-13
Good Flow in a Form
16-14
Internal Controls for Inputs
• The number of inputs should be monitored (to minimize risk
of lost transactions).
– For batch processing
• Use batch control slips
• Use one-for-one checks against post-processing detail reports
– For on-line systems
• Log each transaction as it occurs to a separate audit file
• Validate all data
–
–
–
–
–
–
16-15
Existence checks
Data-type checks
Domain checks
Combination checks
Self-checking digits
Format checks
Common GUI Controls
•
•
•
•
•
•
Text boxes
Radio buttons
Check boxes
List boxes
Drop down lists
Combination
boxes
• Spin boxes
• Buttons
16-16
Common GUI Controls Uses
• Text boxes
– When the input data values are unlimited in scope
• Radio buttons
– When data has limited predefined set of mutually
exclusive values
• Check boxes
– When value set consists of a simple yes or no value
• List boxes
– When data has a large number of possible values
• Drop down lists
– When data has large number of possible values and
screen space is too limited for a list box
• Combination boxes
– To provide user with option of selecting value from a
list or typing a value that may or may not appear in
the list
• Spin boxes
– When need to navigate through a small set of
choices or directly typing a data value
16-17
Advanced Controls
• Drop down
calendars
• Slider edit controls
• Masked edit
controls
• Ellipsis controls
• Alternate
numerical spinners
• Check list boxes
• Check tree boxes
16-18
System User Classifications
Expert User – an experienced computer user
– Spends considerable time using specific application
programs.
– Use of a computer is usually considered non-discretionary.
– In the mainframe computing era, this was called a
dedicated user.
Novice User – a less experienced computer user
– Uses computer on a less frequent, or even occasional,
basis.
– Use of a computer may be viewed as discretionary
(although this is becoming less and less true).
– Sometimes called a casual user.
17-19
Interface Problems
The following problems result in confusion, panic, frustration,
boredom, misuse, abandonment, and other undesirable
consequences.
– Excessive use of computer jargon and acronyms
– Nonobvious or less-than-intuitive design
– Inability to distinguish between alternative actions (“what do I do
next?”)
– Inconsistent problem-solving approaches
– Design inconsistency
17-20
Commandments of User Interface
Design
•
•
•
•
Understand your users and their tasks.
Involve the user in interface design.
Test the system on actual users.
Practice iterative design.
17-21
The User Interface Design Process
1. Chart the user interface dialogue.
State Transition Diagram– a tool used to depict
the sequence and variation of screens that can
occur during a user session.
2. Prototype the dialogue and user
interface.
3. Obtain user feedback.
–
Exercising (or testing) the user interface
4. If necessary return to step 1 or 2
17-22
Design tool
• Balsamiq Mockups
– http://www.balsamiq.com/
• The application has a fully functional 7 day
trial
Capstone Project
• 30% of course grade
– 15% individual project specific “quiz”
– 15% document and project presentation
• Weighted by peer evaluation
• Presentation
– ~ 20 minutes