3. models and theories

Question 1

cognitive model

Answer 1

Represents how users process information perform tasks when interacting with a system.
- These models aim to predict and understand user behaviour with stimulating cognitive processes (perception, memory, decision making and motor actions)
- Help in designing systems that align with natural ways. People think and act
Some important cognitive models in HCI:
1. Model human processor (mhp)
2. GOMS(Goals operators methods and selection rules)
3. Keystroke level model(klm)
4. ACT - R (adaptive control of thought-Rational)
5. Cognitive load theory
6. Mental models
7. dual process theory
8. distributed cognition.

Question 2

MHP
Model Human Processor

Answer 2

Foundational cognitive model that points out the resemblance of human mind to a computer.
Contains three main processors:
1. perceptual systems
Deals with sensory i/p like visual or auditory info
2. cognitive System
Processes the input to form interpretations and decisions
3. motor systems
Cut words decisions into physical actions like typing or clicking.

Question 3

GOMS
Goals operations methods selection rules

Answer 3

Cognitive architecture model designed to predict user behaviour and performance in interaction with the system.
Goals
user’s desired outcome
operators
Cognitive and physical actions users take like clicking typing
methods
Sequence of operators used to accomplish goals
selection rules
Decision criteria uses employee to choose between different methods
- GOMS is particularly useful for task analysis, predicting user efficiency and optimising workflows in system design.

Question 4

Key stroke level model

Answer 4

Simplified version of GOMS that breaks down tasks into basic actions like keystrokes, mouse clicks and delays
This model predicts how long it takes an expert user to complete a task by estimating the time for each action, including pauses for the
keyoperators:
1. keystrokes(k)
2. pointing(p)
3. Homing(H)
4. Drawing(D)
5. Mental operations(M)
KLM is helpful in evaluating the efficiency of user interfaces and systems by analyzing the time taken for low-level interactions.

Question 5

ACT-R
Adaptive control of thought - rational

Answer 5

Cognitive architecture that simulate human cognition by modelling how knowledge is organised in the brain.consists of:
Declarative mem
The info user knows(facts and concepts)
Procedural mem
Knowledge of how to perform a task
cognitive cycles:
1. Perception
recognising external stimuli
2. interpretation
Associating stimuli with new concepts or actions
3. Action
Performing the required fiscal tasks

ACT-R is used to simulate human learning and task performance, offering predictions on how users will behave as they become more familiar with a system.

Question 6

Lingulistic models

Answer 6

These models analyse how users communicate with computers through commands, queries or natural language, how systems can fail to do rules and respond to the inputs efficiently.
- The goal of linguistic models is to create more intuitive, efficient, user friendly leverage in lingualistic principles
applications:
1. Virtual assistants
2. chatbots
3. search engines
4. accessibility interfaces
- BNF grammers are freq used tto specify dialogs.

Question 7

BNF
Backus Naur Form

Answer 7

Defines the grammar and structural interaction between user and system