CS422 - Human Computer Interaction

Instructor: Mehwish AzizSpring: Fall 2010Lecture 1-3

COURSE OUTLINE

What is HCI?• HCI is the study of interaction between people (users) and computers.

• User may be An individual user, a group, an organization or temporally or spatially separated people

• Computer may be Any technology ranging from desktop PCs, to large scale distributed systems or any embedded system.

• Roots of HCI? Computer Science + psychology + cognitive sciences + social sciences and ethnography

• Goal of HCI Make systems user-friendly, highly interactive, efficient and cost effective satisfying the user’s needs –

that means“TECHNOLOGY but USER CENTRIC”

• Why HCI?

• HCI Process

Roots of HCI• Human Factors:

HCI focus is more on users working specifically with computers.

HCI focus on how to implement the computer software and hardware mechanisms to support human-computer interaction.

Thus, human factors is a broader term; HCI could be described as the human factors of computers

• Cognitive ergonomics:Its a part of ergonomics, of which software ergonomics/

HCI is a part.

Roots of HCI• Three areas of study have substantial overlap with HCI:

• Personal Information Management (PIM): Human interactions with the computer are placed in a larger informational context

- people may work with many forms of information, - some computer-based e.g., whiteboards, notebooks In order to understand and effect desired changes in world.

• Computer Supported Cooperative Work (CSCW): Emphasizes on the use of computing systems in support of the collaborative work

of a group of people.

• Human Interaction Management (HIM): Extends the scope of CSCW to an organizational level and can be implemented

without use of computer systems.

Roots of HCI

Computer Science

Human Factors/ Cognitive Science

HCIPIM

CSCWHIM

Goals of HCI• HCI focus on:

Methodologies and processes for designing interfaces - Given a task and a class of users, - Design best possible interface within given constraints - Optimize for a desired property such as

o learning ability or efficiency of use

Methods for implementing interfaces . For example; - Software toolkits and libraries - Efficient algorithms

Goals of HCI• HCI focus on:

Techniques for evaluating and comparing interfaces

Developing new interfaces and interaction techniques

Developing descriptive and predictive models and theories of interaction

• Summarizing, HCI is to design systems that minimize the barrier betweenhuman's cognitive model of what they want to accomplishcomputer's understanding of the user's task

WHY HCI?

Software/Hardware for a User• Can be

Hard to Learn Hard to Remember

Slow to use OR reachability

Error Prone

Frustrating and Unsatisfying to Use

• Leads to a need for transformation in technology!!!!

• Lets review what Microsoft Research Ltd. Published “HCI in the year 2020”

Example: Hard to Learn

Example: Hard to Remember

Example: Slow to Use or Reachability

QUESTIONS• Of Broader Impact: How acceptable will indirect interaction be to society? For

example, will it be acceptable to provide invisible interactive services in public areas like on the beach or in the wilderness?

Will people need to always be provided with an indication they have initiated an interaction?

Should people be allowed to opt in or out of a more connected interactive world?

How should we properly police a connected society for the benefit of all without the technologies of connection becoming misused?

QUESTIONS• For interaction and design:How should new interaction techniques be merged

with pre-existing skills dealing with everyday objects?

If everything we see, touch or walk past is interactive, how will we know and how can we control that interaction?

How useful are conventional definitions of ‘use’ and ‘users’?

QUESTIONS• For Evaluation:How do we design technologies to help people

cope in an increasingly technology-dependent world when the infrastructures break down, devices malfunction or get lost?

What kinds of tasks will be appropriate for computers, and when should humans be in charge?

HCI Process

HCI Process• Design: Understanding design applies the design of everyday things to GUIs - introducing historical roots of HCI

Designing with user includes methodologies for both designing and evaluating interfaces

- with direct user involvement

Designing without the user considers strategies for design - when users are not available

• Implementation: Implementing GUIs gives users’ feedbacks to perform the same process of evaluation and re-designing over built-in systems.

Design PrinciplesAt the design stage, few design principles are to be followed:

• Early focus on user(s) and task(s)

• Empirical Measurement

• Iterative Design: After determining the users, tasks, and empirical measurements to include, perform the following iterative design steps: Design the user interface Test Analyze results Repeat

- Repeat the iterative design process until a sensible, user-friendly interface is created

Human Computer Interface• Human–computer interface is point of communication b/w human and

computer.

• Flow of information b/w human and computer is a loop of interaction which has several aspects including:Task EnvironmentMachine EnvironmentAreas of the Interface Input FlowOutput FlowFeedback

Task Environment: The conditions and goals set upon user.

Machine Environment: The environment that computer is connected to, i.e. a laptop in a college student's dorm room.

Human Computer Interface• Areas of the Interface: Non-overlapping areas involve processes

of the human and computer not pertaining to their interaction.

• Input Flow: The flow of information that begins in the task environment, when the user has some task that requires using their computer.

• Output Flow: The flow of information that originates in the machine environment.

• Feedback: Loops through the interface that evaluate, moderate, and confirm processes as they pass from the human through the interface to the computer and back.

Chapter 1 - Human