HCI - interaction paradigms

UNIT-I: Interaction Paradigms

Overview of Human-Computer Interaction (HCI)

  • Definition of HCI:

    • Study of interaction between users and computers.

    • Design, evaluation, and implementation of interactive computing systems for human use.

    • Understanding phenomena surrounding these interactions.

  • Goals of HCI:

    • Improve interactions between users and computers.

    • Enhance usability and receptiveness to user needs.

    • Minimize barriers between user cognition and computer understanding.

User Interface Definition

  • User Interface (UI):

    • Subset of HCI focused on how people and computers work together.

    • Satisfying user needs effectively.

Factors in HCI Design

  • HCI designers must consider:

    • User expectations and desires.

    • Physical limitations and abilities of users.

    • Functionality of information processing systems.

    • Enjoyability and attractiveness of interfaces.

    • Technical limitations of hardware/software.

  • UI Components:

    • Input: Communication from user to computer (e.g., keyboard, mouse, voice).

    • Output: Results conveyed back to the user (e.g., display screens, sound).

    • Unexplored areas: Senses of smell and touch in interface design.

  • Goals for Effective UI:

    • Minimize noticeability, allowing focus on information/task at hand.

Importance of HCI

  • Critical for software/hardware system development.

  • Powerful applications may be discarded if not user-friendly.

  • Key Focus Areas for HCI Specialists:

    • Understanding psychological and social factors in human-computer systems.

    • Developing methodologies for HCI design.

    • Ensuring effective interactions for both individuals and groups.

Interaction Paradigms: Computing Environments

  • Types of Environments:

    • Physical: Safety, efficiency, workspace conditions (e.g., lighting, noise).

    • Social: Impact of social context on computer use; personal vs. mobile computing.

    • Cognitive: Factors such as age, disabilities, technical knowledge, focus, and cognitive stress.

Analyzing Interaction Paradigms

  • 5W + H Heuristic:

    • Who, What, Where, Why, How: Used to define and analyze interaction paradigms.

    • Components:

      • What/How: Understanding interface components (I/O devices, icons).

      • Where/When: Relates to the physical environment and system type.

      • Who/Why: Looks at tasks and required skill sets.

  • Types of Interaction Paradigms:

    • Large Scale Computing, Personal Computing, Networked Computing, Mobile Computing, Collaborative Environments, Virtual Reality, Augmented Reality.

Large Scale Computing Paradigm

  • What/How:

    • Involves mainframes accessed by remote terminals; use in government and large research.

  • Examples: Supercomputers, specialized machinery for data processing.

  • Who/Why:

    • Primarily for government and corporate research; backbone of the Internet.

Personal Computing Paradigm

  • What/How:

    • Driven by Graphical User Interfaces (GUIs); first example is Xerox Alto (1973).

  • Development:

    • Apple and Microsoft adopted and evolved GUIs.

    • Includes Desktop and Personal-Public Computing.

Networking Computing Paradigm

  • What/How:

    • Systems for communication and resource sharing (WAN, LAN, etc.).

  • Where/When:

    • Users can access resources from any location; internet-based.

  • Who/Why:

    • Global usage; varied applications like banking, gaming.

Mobile Computing Paradigm

  • What/How:

    • Technologies like smartphones; integrates GPS and sensory input.

  • Where/When:

    • Access from any location; supports situational computing.

  • Who/Why:

    • Beneficial for business, healthcare, education, etc.

Collaborative Environment Paradigm

  • What/How:

    • Networks enable group collaboration on shared files.

  • Examples: Groupware technologies for coordination (email, video conferencing).

  • Where/When:

    • Online projects in businesses and education.

Virtual Reality Paradigm

  • What/How:

    • Simulated environments; immersive and interactive spaces.

  • Applications: Training in military, medicine, and job simulations.

Augmented Reality Paradigm

  • What/How:

    • Integrates real and virtual objects to enhance perception.

  • Applications: Military, emergency services, navigation, and education.

Interaction Frameworks and Styles

  • Execution–Evaluation Cycle:

    • Norman’s model: User formulates a plan, executes it, evaluates outcomes.

    • Stages in the cycle: Goal setting, intention formation, action specification, etc.

    • Gulfs:

      • Gulf of Execution: Difference between intended actions and system actions.

      • Gulf of Evaluation: Discrepancy between system output and user expectations.

Interaction Framework

  • Components: System, User, Input, Output.

  • Translation between components crucial for usability assessment.

Coping with Complexity in Interaction Design

  • Tools: Mental models, task-action mappings, semantic/articulatory distances, affordances.

  • Mental Models:

    • User's cognitive representation of interaction with a system.

  • Task-Action Mapping:

    • Links real-world tasks to system actions.

Interaction Styles

  1. Command Line:

    • Fast, flexible but complex; best for expert users.

  2. Menu-Based Interface:

    • Ideal for novice users; potential for information overload.

  3. Form Fill-in:

    • Simplifies data entry; linear flow.

  4. Spreadsheets:

    • Powerful but requires learning.

  5. Question and Answer:

    • Guided interaction, suitable for beginners.

  6. Direct Manipulation:

    • Intuitive, immediate feedback with visual cues.

  7. Metaphors:

    • Relate concepts to real-world; can lead to confusion.

  8. Web Navigation:

    • Link-based vs. search; relies on user interpretation.

  9. 3D Environment:

    • Natural but processor-intensive.

  10. Zoomable Interfaces:

  • Infinite information access; navigated like flying.

  1. Natural Language:

  • User-friendly but can be error-prone.