Logical Design

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Modern Systems Analysis
and Design
Seventh Edition
Jeffrey A. Hoffer
Joey F. George
Joseph S. Valacich
Chapters 10 and 11
Logical Design: Forms and Reports &
Interface and Dialogue
Outline
• Milestone 4
– Overview of Interface
– Output Design
• Prototypes
• Output Data Dictionary
– Input Design
• Prototypes
• Input Data Dictionary
– Navigation System Design
• Prototypes
Joey's Airplane
"Look what I made for you," said Joey, with pride, as he held up a paper airplane. "That's
nice, but it's kinda plain. It's just white with some thin blue lines on it."
"Of course, Silly, it's a piece of notebook paper." But he thought for a moment. "I'll be
back."
Joey went into his room and pulled out his jars of non-toxic tempera paint. First he covered
the plane with a yellow-gold base coat. Then he painted a lovely design in a burgundy
color. He added a few highlights in hunter green. He returned to his sister's room.
"Viola! How do you like this?"
"Wow, that's pretty," his sister replied. "But how does the plane land? Where is the landing
gear?"
"Good idea," said Joey. He returned to his room and fashioned some landing gear out of
paper clips and a couple of buttons.
"Ah, very good," said Susie when she saw it. "But where do the people sit? You need to put
some seats in the plane."
Joey sighed. But he sincerely wanted the plane to be all it could be. Now Joey found a
paper towel tube to act as the cabin. He cut a strip out of the length of it so it could be a
domed roof rather than a cylinder. Then he cut holes for windows. He made seat-backs
out of cardboard. To stay one step ahead of his sister, he placed people in the seats.
They were the little figures from a board game. After fastening it all together with tape
and other various techniques, he brought the plane to his sister, who was now
downstairs.
When she saw it, Susie said, "It's perfect. I'm going to fly it." She ran up the stairs to the
landing and tossed the plane over the banister. It fell to the floor with a clunk.
Joey's Airplane
Moral: If you load up your project with fancy
embellishments, it may look nice, but it won't fly.
Keep your system simple. Bells and whistles are nice,
but every time you add a feature to your system, you
add complication and potential problems. Make sure
you can get your system off the ground before adding
extra features. Stay focused on the main goal of the
system: make sure your system does what it's
supposed to. A plane isn't a plane if it doesn't fly. If
your system does 25 other things, but it doesn't do
what it's supposed to, it's a failure.
Milestone 4
Milestone 4
Phase 3: Design
A. Logical Design
1. Design forms and reports
2. Design interface and dialogues
3. Design database (logical)
B. Physical Design
1. Design physical files and databases
2. Design programs and processes
3. Design distributed systems
Logical Design (Milestone 4)
• Activities
– Output design (i.e., reports)
– Input design (i.e., forms)
– Navigation system design (i.e., menus)
• Output
–
–
–
–
Overview of Interface
Prototypes of input/output/navigation design
Output data dictionary
Input data dictionary
Designing Forms and Reports: Key Concepts
•
Form
–
–
•
A business document that contains some predefined data and may
include some areas where additional data are to be filled in
An instance of a form is typically based on one database record
Report
–
–
–
A business document that contains only predefined data
A passive document for reading or viewing data
Typically contains data from many database records or transactions
The Process of Designing Forms and Reports
• User-focused activity
• Follows a prototyping approach
• Requirements determination
–
–
–
–
–
Who will use the form or report?
What is the purpose of the form or report?
When is the report needed or used?
Where does the form or report need to be delivered and used?
How many people need to use or view the form or report?
• Prototyping
– Initial prototype is designed from requirements
– Users review prototype design and either accept the design or
request changes
– If changes are requested, the construction-evaluationrefinement cycle is repeated until the design is accepted
Output Design
• Why start with output?
• Output should be:
– Accessible
– Timely
– Relevant
– Accurate
– Usable
• Issues:
– Output method
– Output format
– Purpose
– Distribution
– Frequency and timing
– Response time
Report Types
• Hierarchical reports
– Filter report
– Responsibility report
• Comparative reports
– Horizontal report
– Vertical report
• Monitoring reports
– Exception report
– Variance report
Internal Outputs
• Internal Outputs
– Intended for the internal system owners and system users
within an organization
– Detailed reports
• Present information with little or no filtering
– Summary reports
• Categorize information for managers who do not want to wade
through details
• Increasingly presented in graphical formats using charts
– Exception reports
• Filter detailed information before presenting it
External Outputs
• External Outputs
– Leave an organization
Intended for customers, suppliers, partners, or regulatory
agencies.
– Turnaround Documents
• External outputs that eventually re-enter the system as inputs
• Most “bills” and invoices include a stub to be returned by the
customer with payment
External Document
Turnaround Document
Output Implementation Methods
• Printed output
– Tabular output presents information in columns.
– Zoned output places text and numbers into designated “areas”
• Screen output
– Graphic output is the use of pictorial charts to convey information in
ways that demonstrate trends and relationships that cannot be easily seen
in tabular formats.
•
•
•
•
•
Point-of-sale terminals
Multimedia
E-mail
Hyperlinks
Microfilm
– Or microfiche
Taxonomy for Computer-Generated Outputs
Distribution
Internal Output
(reporting)
Delivery
Printer
Detailed, summary, or
exception information
printed on hardcopy
reports for internal
business use.
Common examples:
management reports
Screen
Detailed, summary, or
exception information
displayed on monitors
for internal business
use.
Reports may be tabular
or graphical.
Examples: on-linemanagement reports
and responses to
inquiries
Point-of-Sale
Terminals
Turnaround Output
(external; then
internal)
External Output
(transactions)
Business transactions
printed on business
forms that will
eventually be returned
as input business
transactions.
Business transactions
printed on business
forms that conclude the
business transactions.
Common examples:
phone bills and credit
card bills
Business transactions
displayed on monitors
in forms or windows
that will also be used to
input other data to
initiate a related
transaction.
Examples: web-based
display of stock prices
with the point-and-click
purchase option.
Information printed or
displayed on a special
purpose terminals
dedicated to specific
internal business
functions.
Information printed or
displayed on a special
purpose terminal for the
purpose of initiating a
follow - up business
transaction.
Includes wireless
communication
information
transmission.
Examples: Grocery
store monitor that
allows customer to
monitor scanned prices
to be followed by input
of debit or credit card
payment authorization.
Examples: end-of-shift
cash register balancing
report.
Common examples:
paychecks and bank
statements.
Business transactions
displayed on business
forms that conclude the
business transactions.
Examples: web-based
report detailing banking
transactions
Information printed or
displayed on a special
purpose terminals
dedicated to customers.
Examples: Account
balances display at an
ATM machine or
printout of lottery
tickets. Also, account
information displayed
via television over cable
or satellite.
Taxonomy for Computer-Generated Outputs (concluded)
Distribution
Internal Output
(reporting)
Delivery
Multimedia
(audio or video)
Information
transformed into speech
for internal users.
Turnaround Output
(external; then
internal)
External Output
(transactions)
Information
transformed into speech
for external users who
respond with speech or
tone input data.
Information
transformed into speech
for external users.
Displayed messages
related to internal
business information.
Displayed messages
intended to initiate
business transaction.
Messages related to
Business transactions.
Examples: e-mail
messages announcing
availability of new on-line
business report.
Examples: e-mail messages
whose responses are
required to continue
processing a business
transaction.
Hyperlinks
Web-based links to
internal information that is
enabled via HTML or
XML formats.
Examples: Integration of
all information system
reports into a Web-based
archival system for online archival access.
Web-based links
incorporated into Webbased input pages to
provide users with access
to additional information.
Examples: On a Web
auction page, hyperlinks
into a seller’s performance
history with an invitation to
add a new comment.
Web-based links
incorporated into Webbased transactions.
Examples: hyperlinks to
privacy policy or an
explanation as to how to
interpret or respond to
information in a report or
transaction.
Microfiche
Archival of internal
management reports to
microfilm that requires
minimal physical storage
space.
Examples: Computer
output on microfilm
(COM)
Not applicable unless
there is an internal need to
archive turnaround
documents.
Examples: Computer
output on microfilm
(COM)
Not applicable unless there
is an internal need for
copies of external reports.
Examples: Computer
output on microfilm
(COM)
Not commonly
implemented for
E-mail
Examples: movie trailer
for prospective on-line
Examples: e-mail message
confirmations of business
transactions conducted
via e-commerce on the
Web.
Graphical Output
• When do you use graphs?
• Graph types
–
–
–
–
–
–
Scatter graphs
Line graphs
Bar graphs
Pie charts
Area graphs
Etc…
Principles of Output Design
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
Always have a title (proper wording, page numbers, dates)
Use sections
Include legends
Eliminate computer jargon
Read left to right, top to bottom
Column headings for multi-record layout
Data labels for single record layout
Leave 3 spaces between data fields
Leave 5 spaces between data labels
Right justify numbers, left justify text
Use colors (screen output / color output)
Tabular Report Example
Graph Design
Graphs for
comparison
(a) Line graph
(b) Bar graph
Tabular Report Design Principles
Design
Issue
Page
Size
Page
Orientation
Page
Headings
Report
Legends
Design Guideline
At one time, most reports were printed on
oversized paper. This required special
binding and storage. Today, the page
sizes of choice are standard (8 ½” x 11”)
and legal (8 ½” x 14”). These sizes are
compatible with the predominance of laser
printers in the modern business.
Examples
Not applicable.
Page orientation is the width and length of
a page as it is rotated. The portrait
orientation (e.g., 8 ½ W x 11 L) is often
preferred because it is oriented the way
we orient most books and reports;
however, (e.g., 11 W x 8 ½L) is
often necessitated for tabular reports
because more columns can be printed.
Page headers should appear on every
page. At a minimum, they should include a
recognizable report title, date and time,
and page numbers. Headers may be
consolidated into one line or use multiple
lines.
A legend is an explanation of
abbreviations, colors, or codes used in a
report.
In a printed report, a legend can be
printed on only the first page, or on every
page.
On a display screen, a legend can
Portrait
Landscape
JAN 4, 2001
PAGE 4 OF 6
OVERSUBSCRIPTIONS BY COURSE
REPORT LEGEND:
SEATS
LIM
REQ
RES
USED
AVL
OVR
NUMBER OF SEATS IN THE CLASSROOM
COURSE ENROLLMENT LIMIT
NUMBER OF SEATS REQUESTED BY DEPARTMENT
NUMBER OF RESERVED FOR DEPARTMENT
NUMBER OF SEATS USED BY DEPARTMENT
NUMBER OF SEATS AVAILABLE FOR DEPARTMENT
NUMBER OF OVERSUBSCRIPTIONS FOR DEPARTMENT
Tabular Report Design Principles
Design
Issue
Design Guideline
Examples
Column
Headings
Column headings should be short and
Self-explanatory.
descriptive. If possible, avoid
abbreviations. Unfortunately, this is not
always possible. If abbreviations are used,
include a legend (see above).
Heading
Alignments
The relationship of column headings to the Left justification (good for longer and variable length fields)
actual column data under those headings
can greatly affect readability. Alignment
NAME
should be tested with users for
=========================
preferences with a special emphasis on
XXXXXXXX X XXXXXX
XXX XXXXX
the risk of misinterpretation of the
information.
Right justification (good for some numeric fields;
especially monetary fields). Be sure to align decimal points.
See examples for possibilities (that can
eb
combined)
AMOUNT
=========
$$$,$$$.¢¢
Center (good for fixed length fields and some moderate
length fields)
STATUS
======
XXXX
XXXX
Column
Spacing
Self-explanatory.
The spacing between columns impacts
readability. If the columns are too close,
users may not properly differentiate
between the columns. If they are spaced
too far apart, the user may have difficulty
following a single row all the way across a
page. As a general rule of thumb, place- 3
5 spaces between each column.
Tabular Report Design Principles (concluded)
Design
Issue
Row
Headings
Design Guideline
The first one or two columns should serve
as the identification data that differentiates
each row.
Rows should be sequenced in a fashion
that supports their use. Frequently rows
are sorted on a numerical key or
alphabetically
Examples
By number:
STUDENT ID
===========
999 -38-8476
999 -39-5857
STUDENT NAME
==== ===================
MARY ELLEN KUKOW
By alpha:
SERVICE CANCEL SUBSCR
====== ====== ======
45
345
HBO
Formatting
Control
Breaks
Data is often stored without formatting
characters to save storage space. Outputs
should reformat that data to match the
users’ norms.
Frequently, rows represent groups of
meaningful data. Those groups should be
logically grouped in the report. The
transition from group to the next is called a
control break and is frequently followed by
sub-totals for the group.
As stored:
As output:
307877262
307 -87-7262
8004445454
(800) 444 -5454
02272000
Feb 27, 2000
RANK
====
CPT
CPT
CPT
CPT
NAME
==============
JANEWAY, K
KIRK, J
PICARD, J
SISKO, B
CAPTAINS TOTAL
LTC
LTC
LTC
LTC
CHAKOTAY
DATA
RIKER, W
SPOCK, S
EXEC OFFCR TOTAL
End of
Report
The end of a report should be clearly
indicated to ensure that users have the
entire report.
TOTAL
======
7665
SALARY
======
175,000
225,000
200,000
165,000
-----------765,000 > a control break
110,000
125,000
140,000
155,000
-----------530,000
*** END OF REPORT ***
Screen Output Design Principles
Screen Design
Consideration
Size
Design Guidelines
Different displays support different resolutions. 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. For instance, if some users will have only a 640 x 480 pixel resolution display, don’t
design windows to open at an 800 x 600 pixel resolution.
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 online screens. Given that,
users also require the ability to navigate between screens.
WINDOWS: Outputs appear in windows called forms. A form may display one record or many.
The scroll bar should indicate where you are in the report. Buttons are frequently
provided to move forward and backward through records in the report, and to exit
The report.
INTERNET: Outputs appear in windows called pages. A page may display one record or many.
Buttons or hyperlinks may be used to navigate through records. Custom search
engines can also be used to navigate to specific locations within a report.
Partitioning
WINDOWS: Zonesare forms within forms. Each form is independent of the other but can be
related. The zones can be independently scrollable. The Microsoft Outlook bar is
one example. Zones can be used for legends or control breaks that take the user
to different sections within a report.
INTERNET: Frames are pages within pages. Users can scroll independently within pages.
Frames can enhance reports in many ways. They can be used for a legend, table
of contents, or summary information.
Screen Output Design Principles (concluded)
Screen Design
Consideration
Information
Hiding
Highlighting
Design Guidelines
On-line applications such as those that run under Windows or within an Internet browser offer
capabilities to hide information until it is either needed or becomes important. Examples of such
information hiding include:

Drill-down controls that show minimal information and provide readers with simple ways
to expand or contract the level of detail displayed.
In Windows outputs the use of a small plus- or minus-sign in a small box to
o
the left of a data record offers the option of expanding or contracting the
record into more or less detail. All of this expansion and contraction occurs
within the output’s window.
In Intranet applications, any given piece of summary information can be
o
highlighted as a hyperlink to expand that information into greater detail.
Typically, the expanded information is opened in a separate Window so the
reader can use the browser’s forward and backward buttons to switch
between levels of detail.

Pop-up dialog boxes may be triggered by information
Highlighting can be used in reports to call users’ attention to erroneous data, exception data, or
specific problems. Highlighting can also be a distraction if misused. On-going human factors
research will continue to guide our future use of highlighting. Examples of highlighting include:






Printing
Color (avoid colors that the colorblind cannot distinguish)
Font and case (changing case can draw attention)
Justification (left, right, or centered)
Hyphenation (not recommended in reports)
Blinking (can draw attention or become annoying)
Reverse video
For many users, there is still comfort in printed reports. Always provide users the option to print
a permanent copy of the report. For Internet use, reports may need to be made available in
industry standard formats such as Adobe Acrobat, which allows users to open and read those
reports using free and widely available software.
Output Data Dictionary
• Used to map the output to the elements of the system.
• Specifies the distribution, frequency, and output
method, among others.
Input Design
Forms of Input
–
–
–
–
Manual paper forms
Electronic input forms
Direct-entry devices
Document image processing
Input Implementation Methods
•
•
•
•
•
Keyboard
Mouse
Point-of-sale terminals
Sound and speech
Automatic data capture
–
–
–
–
–
–
Optical mark recognition (OMR)
Optical character recognition (OCR)
Magnetic Ink
Electromagnetic transmission
Smart cards
Biometric
Features That Affect User Interface Design
•
•
•
•
•
•
•
Display area
Character sets and graphics
Paging and scrolling
Color displays and display properties
Split-screen and windowing capabilities
Keyboards and function keys
Pointer options
Principles of Electronic Input Design
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Coordinate input screens with paper forms
Sequence the input from left to right, top to bottom
Use upper and lower case
Use text grouping to aid in understanding
Use familiar field labels
Be consistent for entry
Enter only variable data (do not input data that can be calculated or stored)
Validate data -- When to validate?
Use function keys -- Placement of function keys
Visible space and boundaries for data entry
Indicate optional fields
Completion signal
Provide clearly marked exits
Special field entries
Minimize user’s memory load
Permit easy reversal
Screen messages
Bad Flow in a Form
Good Flow in a Form
Screen Zones
Title
Menus & Tools
Body & Pop-ups
Messages and Status
F
l
a
g
s
Poor Form Design
Poorly designed form
Improved Form Design
Improved design for
form
Poor Form Design
Poorly designed form
Improved Form Design
Improved design for
form
Input Data Dictionary
• Map the input to the elements of the system
Designing Interfaces and Dialogues
Interfaces and Dialogues
• Focus on how information is provided to and captured
from users
• Dialogues are analogous to a conversation between
two people
• A good human-computer interface provides a unifying
structure for finding, viewing and invoking the
different components of a system
Navigation: System User Classifications
Expert User
• An experienced computer user who will spend
considerable time using specific application programs.
• In the mainframe computing era, this was called a
dedicated user.
Novice User
• Sometimes called a casual user
• A less experienced computer user who will generally
use a computer on a less frequent, or even occasional,
basis.
Interaction Methods and Devices
– Command Language Interaction
• Users enter explicit statements into a system to invoke operations
• Example from MS DOS:
– COPY C:PAPER.DOC A:PAPER.DOC
– Command copies a file from C: drive to A: drive
– Menu Interaction
• A list of system options is provided
• A specific command is invoked by user selection of a menu
option
• Menu complexity varies according to needs of system and
capabilities of development environment
• Hierarchies can be employed
• Two common placement methods
– Pop-up
– Drop-down
• Table 11-1 presents general guidelines for designing menus
Interaction Methods and Devices
– Form Interaction
• Allows users to fill in the blanks when working with a system
– Object-Based Interaction
• Symbols are used to represent commands or functions
• Icons
– Graphic symbols that look like the processing option they are meant to
represent
– Use little screen space
– Can be easily understood by users
– Natural Language Interaction
• Inputs to and outputs from system are in a conventional speaking
language like English
Navigation
Menus
• Simple menus
• Pull-down menus
• Pop-up menus
• Nested menus
• Shingles, tiles, and icons
(toolbars)
• Touch menus
• Sound cues
• Hyperlinks
Command Language
• “expert” menus
• Purely textual, driven via
commands
• Examples:
– Truncation
– Vowel Drop
– First and Last Letter
– Phonics Sound
– Standard Abbreviation
Special Considerations for User Interface Design
• Internal controls—authentication and authorization
• On-line help
Authentication Log-in Screen
Authentication Error Screen
Error Messages
Poor Error Messages
Improved Error Messages
ERROR 56 OPENING FILE
The file name you typed was not found. Press
F2 to list valid file names.
WRONG CHOICE
Please enter an option from the menu.
DATA ENTRY ERROR
The prior entry contains a value outside the
range of acceptable values. The entry must be
between the values of 0 and 100.
FILE CREATION ERROR
The file name you entered already exists.
Providing Feedback
1.
Status Information
–
–
2.
Keeps users informed of what is going on in system
Displaying status information is especially important if the operation
takes longer than a second or two
Prompting Cues
–
Best to keep as specific as possible
3. Error and Warning Messages
–
–
–
–
Messages should be specific and free of error codes and jargon
User should be guided toward a result rather than scolded
Use terms familiar to user
Be consistent in format and placement of messages
Providing Help
• Place yourself in user’s place when designing help
• Guidelines
– Simplicity
• Help messages should be short and to the point
– Organization
• Information in help messages should be easily absorbed by users
– Demonstrate
• It is useful to explicitly show users how to perform an operation
• Context-Sensitive Help
– Enables user to get field-specific help
• Users should always be returned to where they were
when requesting help
Poor Design of a Help Screen
Poorly designed help
screen with many
violations of the
general guidelines for
displaying text
Improved Design of a Help Screen
An improved design
for a help screen
Menu Design
•
•
•
•
Use familiar and consistent terminology
Ensure that items are distinct
Bring keyword to left
Establish guidelines
–
–
–
–
–
–
Titles
Placement
Instructions
Error messages
Selection of menu items
Limit items to 7 ± 2
Overview of Interface
• Hierarchy Chart of the entire navigation system,
including all input and output programs
– This must match the prototyped navigation system.
– This must also match the DFDs.
• Alphabetically list each of the items from the
hierarchy chart in a document and provide:
– Name
– Description of the program
Output of Phase 3A (Milestone 4)
• Overview of Interface
• Output Prototypes (three) and accompanying data
dictionaries
• Input Prototypes (three) and accompanying data
dictionaries
• Complete Navigation System Prototyped
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