CS 3724 Introduction to Human Computer Interaction Section 2 CRN MW 2:30-3: McB

When computers look at users do they see people as just another machine?

WARNING The next few lectures will warp your thinking! Dangerous and seductive ideas will be discussed. Take good notes, but don’t be fooled. DISCLAIMER: The instructors and GTA’s do not endorse the idea of thinking of users as machines or computers.

The Roots of HCI, Revisited  The Cognitive Revolution  Information Theory  What can the human computer do?  Sensors and actuators  Problem solving  Reasoning

The Roots of HCI, Revisited  The Cognitive Revolution  Information Theory  What can the human computer do?  Sensors and actuators  Problem solving  Reasoning

The Cognitive Revolution

 Confluence of psychology, computer science, philosophy, linguistics --> transformed all  Representations of external world  Categorizing  Concepts  Prototypes  Hierarchies  Schemas

The Cognitive Revolution  Donald Broadbent  Flow chart thinking process  More on that later…  Herbert Simon  Symbolic processing  Jerome Bruner (not in video)  Categorization

HCI Pioneers / Cognitive Psychologists  Tom Moran  Stu Card  Don Norman  Ben Schniederman  Bob Kraut  Marilyn Mantei  John Carroll

The Roots of HCI, Revisited  The Cognitive Revolution  Information Theory  What can the human computer do?  Sensors and actuators  Reasoning  Problem solving

Information Theory  What is information?  Communication model:  Sender  Medium  Signal  Noise  Receiver  Claude Shannon  the “bit”

Turing Machine  Given a string of symbols on the tape, a Turing machine starts at the initial state.  At any state it reads the symbol under the head, either erases it or replaces it with a symbol (possibly the same symbol).  It then moves the head to left or right or does not move it and goes to the next state which may be the same as the current state.  One of its states is the halt state and when the Turing machine goes into the halt state, it stops its operation.

 “Mechanical model”  Babbage  Lovelace  Atanasoff  Eckert  Mauchly  Turing  Simon  Broadbent Information Processing Model of Cognition

 Broadbent  Flow and control:  Input  Memory  CPU: filter  CPU: process  Output

The Roots of HCI, Revisited  The Cognitive Revolution  Information Theory  What can the human computer do?  Sensors and actuators  Problem solving  Reasoning

What can the human computer do? Some information processing ways of thinking about users:  Bandwidth of visual channel  Filtering of information  Synchronous vs. asynchronous communication  Measuring human memory in “bits”

The Roots of HCI, Revisited  The Cognitive Revolution  Information Theory  What can the human computer do?  Sensors and actuators  Problem solving  Reasoning

What can the human computer do? How fast can users type? Where do users look? How much can users read at once? Why is “ YELLOW GREEN BLUE RED INDIGO’ confusing? Is a mouse or trackball better? If a button is quickly located, can it also be quickly hit?

HEY -- What about human factors and ergonomics?

Beginning in World War II, engineers and psychologists were concerned with how to improve control systems -- particularly in aircraft. “Human factors” and “ergonomics” emerged as an engineering practice. But there was no unifying model or theory, just measurements and resulting heuristics. Without a compelling comprehensive model (i.e. information processing), measuring human performance became a tool for evaluating details of cognition.

The Roots of HCI, Revisited  The Cognitive Revolution  Information Theory  What can the human computer do?  Sensors and actuators  Problem solving  Reasoning

What can the human computer do? How do users find information using a search engine like GOOGLE? How is that different from the search techniques they use at the library? How do users figure out when to use the keyboard and when to use the mouse? What happens when people get distracted by something interesting in a GOOGLE search? (Is the distraction “noise” or something else?)

The Roots of HCI, Revisited  The Cognitive Revolution  Information Theory  What can the human computer do?  Sensors and actuators  Problem solving  Reasoning

What can the human computer do? How do users make sense of information? How do people learn to use computer applications? Is it like learning to read? What patterns do users see? What patterns don’t they see? How can computers and people communicate using users’ natural language?

The Roots of HCI, Revisited  The Cognitive Revolution  Information Theory  What can the human computer do?  Sensors and actuators  Problem solving  Reasoning

Turing Test

Turing Test: ELIZA  Joseph Weizenbaum  1966  Most enduring code ever written?  “Chatbot”  Demonstrates weakness of AI and Turing Test * Hello > How are you today.. What would you like to discuss? * Are you a Rogerian or rotarian? > Perhaps in your fantasies I am a Rogerian or rotarian? * Why would I fantasize about you? I don't even know you? > Do you wish to be able to even know me? * No > Are you saying no just to be negative? * No > Come, come, elucidate your thoughts.

The Roots of HCI, Revisited  The Cognitive Revolution  Information Theory  What can the human computer do?  Sensors and actuators  Problem solving  Reasoning

OK -- How do we optimize this system? What are the limits of users?

For next time…  Chat with an ELIZA      Read Chapter 7  Team Project, due next week:  Working prototype  Show GTA (arrange time!)  Brief report of functionality  Next lectures: usability testing