2/6/2022

Lecture # 14 HCI: Some Terms of Interaction

Models of Interaction
• terms of interaction domain – the area of work under study
e.g. graphic design

• Norman model goal – what you want to achieve

e.g. create a solid red triangle
task – how you go about doing it
• interaction framework – ultimately in terms of operations or actions
e.g. … select fill tool, click over triangle

Note …
• traditional interaction …
• use of terms differs a lot especially task/goal !!!

Donald Norman’s Model 7 Stages of Action

• Norman’s model concentrates on user’s view of the interface Goals

Intention to act Evaluation of the

Interpretations

sequence of actions Interpreting the perception

goal

execution evaluation execution of Perceiving the state

The action sequence of the world
system

THE WORLD

HCI and Frameworks Ergonomics

• physical aspects of interfaces

• industrial interfaces
Study of the physical characteristics of interaction

• Also known as human factors – but this can also be used to mean much of HCI!

• Ergonomics good at defining standards and guidelines for constraining the way
we design certain aspects of systems
• “Ergonomics (or human factors) is the scientific discipline concerned with the
understanding of interactions among humans and other elements of a system,
and the profession that applies theory, principles, data and methods to design in
order to optimize human well-being and overall system performance.”

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Physical Aspects of Interfaces Industrial Interfaces

• arrangement of controls and displays Office interface vs. industrial interface?
• controls grouped according to function or frequency of use, or sequentially
• surrounding environment Context matters!
• seating arrangements adaptable to cope with all sizes of user
• health issues office industrial
• physical position, environmental conditions (temperature, humidity),
lighting, noise,
type of data textual numeric
• use of colour rate of change slow fast
• use of red for warning, green for okay, environment clean dirty
awareness of colour-blindness etc.

… the oil soaked mouse

Defferent Interfaces:
Glass Interfaces ? Indirect Manipulation
• industrial interface: • office– direct manipulation
• traditional … dials and knobs – user interacts
• now … screens and keypads with artificial world
system
• glass interface
+ cheaper, more flexible,
Vessel B Temp
multiple representations, • industrial – indirect manipulation
precise values 0 100 200 – user interacts
• not physically located, with real world
loss of context, through interface
complex interfaces 113 • issues .. plant
• may need both interface
– feedback
– delays immediate
multiple representations
of same information feedback

instruments

Interaction Styles Common Interaction Styles

• dialogue … computer and user
• command line interface
• distinct styles of interaction
• menus
• natural language
• question/answer and query dialogue
• form-fills and spreadsheets
• WIMP
• point and click
• three–dimensional interfaces

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Command line interface Menus

• Set of options displayed on the screen
• Way of expressing instructions to the computer directly
• function keys, single characters, short abbreviations, whole words, or a • Options visible
combination • less recall - easier to use
• rely on recognition so names should be meaningful
• suitable for repetitive tasks
• better for expert users than novices • Selection by:
• numbers, letters, arrow keys, mouse
• offers direct access to system functionality • combination (e.g. mouse plus accelerators)
• command names/abbreviations should be meaningful!
• Often options hierarchically grouped
Typical example: the Unix system, DOS , Telnet • sensible grouping is needed

• Restricted form of full WIMP system

Natural language Query Interfaces

• Familiar to user • Question/answer interfaces

• speech recognition or typed natural language • user led through interaction via series of questions
• suitable for novice users but restricted functionality
• Problems • often used in information
• vague systems
• ambiguous
• hard to do well!
• Solutions
• try to understand a subset
• pick on key words

Query Interfaces Form-fills

• Query languages (e.g. SQL)

• used to retrieve information from database • Primarily for data entry or data retrieval
• requires understanding of database structure and language syntax, hence
requires some expertise
• Screen like paper form.
Select from Employee
Where Salary > 30,000
• Data put in relevant place

• Requires
• good design
• obvious correction
facilities

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Form-fills Spreadsheets

• first spreadsheet VISICALC, followed by Lotus 1-2-3

MS Excel most common today

• sophisticated variation of form-filling.

• grid of cells contain a value or a formula
• formula can involve values of other cells
e.g. sum of all cells in this column
• user can enter and alter data spreadsheet maintains consistency

WIMP Interface Point and Click Interfaces

Windows • used in ..
• multimedia
Icons • web browsers
Menus • hypertext
Pointers
• just click something!
… or windows, icons, mice, and pull-down menus! • icons, text links or location on map

• minimal typing
• default style for majority of interactive computer systems, especially PCs
and desktop machines

Three Dimensional Interfaces Elements of the WIMP Interface

• virtual reality • windows, icons, menus, pointers

• ‘ordinary’ window systems
• highlighting • buttons, toolbars,
• visual affordance
• indiscriminate use
just confusing! • palettes, dialog boxes
• 3D workspaces
• use for extra virtual space
• light and occlusion give depth
• distance effects

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Windows Windows

• Areas of the screen that behave as if they were independent • scrollbars

• can contain text or graphics
• can be moved or resized
• can overlap and obscure each other, or can be laid out next to one another
(tiled)

• title bars

Icons Pointers

• small picture or image • important component

• represents some object in the interface • WIMP style relies on pointing and selecting things
• often a window or action • uses mouse, trackpad, joystick, trackball, cursor keys or keyboard
• windows can be closed down (iconised) shortcuts
• small representation fi many accessible windows • wide variety of graphical images
• icons can be many and various
• highly stylized
• realistic representations.

Menus Menus

• Choice of operations or services offered on the screen

• Required option selected with pointer

problem – take a lot of screen space

solution – pop-up: menu appears when needed

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Kinds of Menus Pull-down Menu

• Menu Bar at top of screen (normally), menu drags down

• pull-down menu - mouse hold and drag down menu
• drop-down menu - mouse click reveals menu
• fall-down menus - mouse just moves over bar!

• Contextual menu appears where you are

• pop-up menus - actions for selected object
• pie menus - arranged in a circle
• easier to select item (larger target area)
• quicker (same distance to any option)
… but not widely used!

Drop-down Menu Fall-down Menus

Pop-up Menus Pie Menu

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Menus Extras Keyboard Accelerators

• Cascading menus
• hierarchical menu structure
• menu selection opens new menu
• and so in ad infinitum

• Keyboard accelerators
• key combinations - same effect as menu item Alt + T
• two kinds
• active when menu open – usually first letter
• active when menu closed – usually Ctrl + letter
usually different

Menus Design Issues Buttons

• which kind to use • individual and isolated regions within a display that can be selected
to invoke an action

• what to include in menus at all

• Special kinds
• words to use (action or description) • radio buttons
– set of mutually exclusive choices
• check boxes
– set of non-exclusive choices
• how to group items

• choice of keyboard accelerators

Radio Buttons Check Boxes

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Toolbars Customization

• long lines of icons …

… but what do they do?

• fast access to common actions

• often customizable:
• choose which toolbars to see
• choose what options are on it

Customization Palettes and Tear-off Menus

• Problem
menu not there when you want it

• Solution
palettes – little windows of actions
• shown/hidden via menu option
e.g. available shapes in drawing package
tear-off and pin-up menus
• menu ‘tears off’ to become palette

Palettes and Tear-off Menus Dialogue Boxes

• information windows that pop up to inform of an important event or

request information.