Conceptual model
◼ A conceptual model is a high-level description of how a system is organized and operates.
◼ An abstraction that outlines what people can do with a product and what concepts are needed to understand in order to interact with the product.
- The designer should provide a good conceptual model for the user, presenting operations and results in a coherent, consistent system image.
People build their own…?
system of how things work, e.g. car. But the designer can help users foster an appropriate conceptual model.
How do the designer help the user foster an appropriate conceptual model?
Appearance, instructions, behavior
What should a conceptual model comprise? (4)
- The major metaphors(used to convey to the user how to understand what a product is for and how to use
- Concepts that users are exposed to through the product, including the task-domain objects they create and manipulate, their attributes, and the operations that can be performed on them
- The relationships between those concepts
- The mappings between the concepts and the user experience the product is designed to support or invoke
Why use metaphors?
Metaphor can facilitate learning by allowing users to dram upon the knowledge they already have about the reference system
Motstånd till metaphors?
- break the rules, too constraining, not being able to understand the systems functionality beyond metaphor, limits the designer’s imagination in conjuring tup the new paradigms and models
Interactive Input Devices?
- Input Device is any machine that feeds data info a computer
(Interactive Input Devices) Devices that rely on vision?
- keyboards
- pointing device
Fitts’ Law?
Time (in msec) = a + b log2(D/S +1)
Where:
a, b = constants (empirically derived)
D = distance
S = size (width of the target)
Index of Difficulty (ID) = log2(D/S+1)
Voice recognition is a….?
Input device
Output devices?
◼ Output Device is a machine capable of representing data from a computer.
◼ Visual Display: data may take the form of graphic, tabular, text or other.
◼ Response time
◼ Interactive dialogue
Synthesized speech is appropriate when: (6)
◼ The required message is short and simple,
◼ The message needs an immediate response,
◼ The user/receiver is visually occupied,
◼ The environment is too brightly or poorly lit for ordinary visual displays to be used,
◼ The user is moving around too much to visually attend to a single screen, or
◼ No screen exists but an audio receiver does (e.g., telephone).
When Auditory Output-Nonspeech
- Receiving calls, Windows Startup, shutdown
Advantages of Auditory Output-Nonspeech (5)
◼ Reinforcement of vision and hearing (dual coding theory) ◼ Faster reaction ◼ Reduction of visual load ◼ To simplify the screen ◼ To grab attention ◼ To support visually impaired users
Drawbacksof Auditory Output-Nonspeech (3)
◼ Inability to differentiate between similar sounds
◼ Transience
◼ Annoyance
Paradigms in HCI
Refers to a particular approach that has been adopted by a community in terms of shared assumptions, concepts, values and practices.
Ex. - Many new tech advances led to a new generation of user-computer environments. e.g., virtual reality, multimedia, collaborative interfaces, ubiquitous computing, internet of things
Command Language Interface. Advantages? (4)
◼ Powerful
- Complex commands can get much done
- Complex procedures may be stored as scripts/macros
◼ Flexible, user controlled
- User can do anything in any order.
◼ Fast, efficient
- Can be very fast and efficient for experts despite required typing
◼ Uses minimal “screen estate”
- Only one line required for command entry
Command Language Interface. Limitations? (4)
◼ Difficult to learn
- Cryptic command names and arbitrary syntactic delimiters must need rote memory.
◼ Difficult to remember
- Infrequent users won’t achieve mastery
◼ Assumes typing skill
◼ Error prone
◼ Enhancements are invisible
- The interface may not reflect any changes and enhancements made to the system
Advantages - Menu-based Interaction (5)
◼ Self-explanatory
- Menu systems make clear what can be done (semantics) and how to do it (syntax).
◼ Requires little human memory ◼ Few keystrokes
◼ Easy error handling
◼ Outcomes are visible
Limitations - Menu-based Interaction (4)
◼ Inefficient
◼ Inflexible
◼ Impractical for numerous choices - How to group options?
- How to name options?
◼ Takes up screen “real estate”Button?
Simulated-3D raised aspect – visual affordance
Butcons?
Icons that serve as buttons ( Easy to use and memorize)
Toolbars
Visible, immediate commands.
Toolbars: The Ribbon
Tabbed toolbar with textual labels for groups of functions & presentation of butcons and textual commands
