Input and Output Design

1
Input and Output Design

• MIS 441 User Interface Design, Prototyping, and
  Evaluation
• April 25, 2000

2
Agenda

• Input Design Terminology
• Automatic Data Collection technologies
• Input Design Issues
• Screen-Based Controls
• Output Design Terminology
• Graphic Output
• Output Design Issues

3
Terminology

• Input Design
• process whose goal is to capture covert data
  into a form suitable for the computer
• Data Capture (Example collecting a source
  document)
• the identification of new data to be input
• Data Entry (Example Typing a name in a form)
• the process of translating a source document into
  machine-readable format.
• Data Input (Example clicking Enter on the data
  entry form)
• the actual entry of data in machine-readable
  format into the computer

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Automatic Data Collection Technologies

• Biometric (Example James Bonds retinal
  scanner)
• compare a persons finger print, voice pattern,
  or retinal scan to see if it matches stored data
• Electromagnetic (Example Smart toll booths)
• identifies objects by recognizing radio
  frequencies emitted from a tagged object
• Magnetic
• magnetic stripe cards (Example your ATM card)
• MICR (Example the bottom of your checks)

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Automatic Data CollectionTechnologies
(continued)

• Optical (Example bar coding)
• lasers read data indicated by a sequence of bars
  
• Smart Cards (Example your Cat Card)
• card with a microprocessor that can store data
• Touch (Example SILK screens)
• data is captured when a person touches the screen
  or writes on the screen with an electronic pe

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Input Design Issues

• Minimize volume of input data
• capture only variable data
• capture only individual data elements. Let
  computer handle calculated fields
  already-stored data
• Use codes where possible (ex tax-rate table
  lookup)
• Ease Translation of Source Documents
• Include instructions sources of help
• Minimize writing - use check boxes option
  buttons
• Organize source document based on Users
  Conceptual Model in U.S. it should be read like
  a book, from top-to-bottom and from left-to-right

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Input Controls

• Keep track of the number of inputs
• Account for each input document
• Cross check totals where possible
• Save transactions to a log file in case of
  disaster
• Validate Data
• Make sure required fields have been entered
• Limit Range checks
• Field Relationship checks
• Check digits
• Format checks

8
Screen-Based Controls

• Labels
• Text Boxes
• Option Buttons
• Check Boxes
• List Boxes
• Combo Boxes

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Label Controls

• Displays text
• The user cannot enter text
• Use Label Controls when you want to present
  information that the user will not be able to
  change
• Examples Labels for other Controls, Calculated
  Fields that should not be altered by the user

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Text Boxes

• The user types the data
• Use text boxes when you cant provide the user
  with a meaningful list of values from which to
  choose or when values are unlimited
• Examples Customer Name, Temperature to Convert
  to Celsius, Product Number
• If text data is large, such as a product
  description, use Memo Box

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Option Button Controls

• Also called Radio Buttons
• User selects one option from a small number of
  predefined, mutually-exclusive options
• One of the options will be the default option
  when the control first appears
• Examples Number of Apartment Bedrooms

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Check Box Controls

• User selects one of only two options Yes or No
  (Check Mark or No Check Mark)
• One of the options will be the default option
  when the control first appears
• Make sure Check Box options are truly Yes/No and
  create captions that clearly indicate this
• Examples Doctors Office questions
• Have you ever had measles?
• Have you ever had meningitis?
• Are you now or have you ever been a Communist?

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List Box Controls

• Select from a list of predefined,
  mutually-exclusive options
• Use when number of items in list is too large for
  a group of option buttons OR when limited screen
  space prohibits the use of a group of option
  buttons
• Scroll bars appear when list is too long
• Default list item is usually highlighted
• Examples U.S. States, Zodiac Sign

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Combo Box Controls

• Combination of a List Box a Text Box
• Use Combo Boxes when the user can choose from a
  list of possible options OR type an option of his
  choosing
• Examples Font Sizes, Favourite Ice Cream Flavour
  

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Tips for Screen-Based Controls

• Focus on Fewer Errors - which control is likely
  to cause fewest input errors?
• Group related controls, align them vertically,
  and give them a clear caption
• Provide ToolTips whenever possible
• Use Drop-Down List Boxes when screen space is
  limited
• Make sure Check Box options are truly Yes/No
• Adhere to industry screen design standards

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More Tips on Input Devices

• Dont focus exclusively on Keyboard Mouse.
  Would a Joystick, Trackball, or Voice system be
  more effective for your users?
• Access Keys are vital with a mouseless system.
  But avoid using them for frequently-performed
  functions.
• Dont create an application where it is necessary
  to pick up move the mouse to increase the range
  of the pointer. This happens when the mouse is
  tied to the displayed area instead to the screen
  size.
• Only one mouse button is really necessary. One
  button (Left, on a right-handed mouse) should
  activate main functions.

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Input attribute table
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Designing Healthy Interfaces

• Bad UI design can cause Repetitive Strain
  Injuries, so
• Minimize keystrokes to those just needed for text
• Create a system that remembers defaults to
  users last input.
• To avoid eye strain,
• Avoid high contrasts between background colors
  text.
• Dont require users to navigate the mouse to a
  specific pixel (A pixel is .07 MM wide
  - less than the width of a pin!
• The more frequent a function, the bigger its icon
  should be
• If there is only one thing a user can do next,
  do it for them!

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Motivation for Output Design

• Outputs
• Present information to system users
• Justification for the system
• Goals of Output Design
• Communicate Match the representation to the
  capabilities of the user (i.e., make
  relationships clear)
• Economize Do the most with the least amount of
  cues (i.e., reduce cognitive load of the user)
• Organize Present pertinent information to system
  users that is easy to read and easy to use

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Output Design Terminology

• Output Types
• External Output for outside users
  examples are paychecks,
  invoices, itineraries, purchase orders
• Turnaround outputs eventually come back as system
  input, an example is a form designed
  to gather input from a customer
• Internal Output for systems users managers
  examples
  are CPU or disk storage capacity reports, system
  access (security) warnings
• Report Typesa video store example
• Detailed Reports (show me the details of todays
  transactions)
• Summary Reports (show me the totals by genre for
  last month)
• Exception Reports (show me customers whose unpaid
  late fees amount to more than 50)

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Other outputs to consider

• Error messages
• E.g., inputs are invalid
• Verification of task completion
• E.g., print job is complete, mail was sent
• System updates on task progress
• E.g., showing of document saved, showing of
  pages sent to the printer

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Types of outputs

• External outputs
• Leave the system
• Trigger actions in, or conform actions to,
  recipients
• Turnaround outputs
• Implemented as a form that eventually re-enters
  the system as an input
• Internal outputs
• Remains within the system
• Common in decision support systems (DSS)

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Internal outputs
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Output Media

• Storage Devices
• Magnetic Tape, Disk Packs
• CDs
• Floppies
• Hard Drive
• Video
• Paper
• Email Fax
• Sound

25
Graphic Output

• Bar Charts (Compare Values)
• Column Charts (Compare Values Over Time)
• Pie Charts (Compare Parts to the Whole)
• Line Charts (Show Trends Over Time)
• Scatter Charts (Show data clusters)

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Output Design Issues

• Easy to Interpret
• Include a meaningful title
• Group related sections provide section headings
• Use legends to define all fields
• Dont overcrowd
• Information gets to the right people
• Information is timely

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Designing Outputs

• Identify outputs
• Select medium format
• Prototype the output for users

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Output attribute table