DESIGN AND EVALUATION

HCI Class Presentation

Group Members:

Petra Leimert, Alexander Stevenson,

Martin Kyle, Farhan Mohamed, Lisa Tong

Overview Design Principles Design Goals Design Process Design Methodologies

User Centered Heuristics

Design Principles Know the user

Minimize memorization Allowing selection of items rather than entry of data Using names instead of numbers

Optimize operations Providing rapid execution of common operations Preserving display consistency

Engineer for errors Allowing actions to be reversible Guaranteeing system integrity in the face of hardware or software

failure

Design High Level Goals Comber, 1996

Aesthetics Navigation Comprehension Learnability Efficiency Memorability Error handling User satisfaction

Design Methodologies Gould, Boies, and Lewis (1991)’s four design principles

Early focus on users Talk with user Visit customer locations …

Early-and continual-user testing Early user manuals Mock-ups Field studies …

Iterative design Software tools System develoment work organization

Integrated design Consider all aspects of usability in the initial design One person or group has responsibility for all aspects of usability

Design Methodologies Rubinstein and Hersh (1984)

Information collection Goals, Market requirements, technical requirements Current state of the art, competing products Industry stansards, government regulation …

System design External myth, conceptual model, and use model Methods for error handling and recovery

Implementation Prototype and System

Evaluation Formal and informal

Deployment Delivery, evaluation of the reactions of the user and the marketplace to it

Design Methodologies SIGCHI 1999 Survey

HCI Professionals attending SIGCHI 1999 were surveyed about what design methodologies they thought were most effective. These survey results were published the following year.

e.g. Rosenbaum, Rohn, and Homburg. A Toolkit for Strategic Usability. 2000. CHI Letters.

Design Approaches The most promising approach

Iterate design and evaluation until a satisfactory result is achieved

Process Evaluation of existing systems, Evaluation of current work practices and

organizational setting, Evaluations of rapid prototypes and mock-ups, Evaluations of alpha and beta versions FEEDBACK INTO DEVELOPMENT CYCLE

Design Process Activities in the development cycle

Requirements specification

Architectural design

Detailed design

Coding and unit testing

Integration and testing

Evaluation and maintenance

Requirements and Specifications Brooks

“I believe the hard part of building software to be the specification, design, and testing of this conceptual construct, not the labor of representing it and testing the fidelity of the representation.”

From “No Silver Bullet”

Interaction Design Applied

Interaction Design Applied

Interaction Design Applied

Interaction Design Applied

Design Methodologies Our Focus Today

User Centered Design Heuristics

User Centered Design Enhanced approach to development:

User profiles User requirements Participatory Methods Usability Testing Iterative design and evaluation

User Centered Design Process Adapted from Preece, 1993

Design

ImplementationEvaluation

Summative evaluation

Formative evaluation

Usability testing

Task analysis Standards-Guidelines

Design history

Design tools

Requirements analysis

User Profiles Understand user at many levels

Social Condition Education Level Personal Interests Computer Literacy System Role

Participatory Methods Wishlists Beta Programs Feature Councils

Heuristic Design & Evaluation Systems are designed by looking at a small

set of very general “design guidelines” (called heuristics).

Heuristics often help designers avoid common pitfalls in human computer interaction.

Heuristic Guidelines for Dialog Design

“Eight Golden Rules of Dialog Design” Shneiderman (1992) Strive for consistency Enable frequent users to use shortcut Offer informative feedback Design dialogues to yield closure Offer simple error handling Permit easy reversal of actions Support internal locus of control Reduce short-term memory load

Heuristic Evaluation A sample problem (telephone banking)

Enter ‘1’ for account info.‘3’ for transfers

Heuristic Evaluation A sample problem (telephone banking)

Enter account to transfer from

Heuristic Evaluation A sample problem (telephone banking)

Enter account to transfer to

(an abbreviation for the checking account)

Heuristic Evaluation A sample problem (telephone banking)

Enter amount in cents

Heuristic Evaluation A sample problem (telephone banking)

From account number 12345 to accountNumber primary account, a transfer of 1000 dollars is to be made. Press ‘1’ toConfirm, ‘0’ to cancel.

Heuristic Evaluation A sample problem (telephone banking)

You do not have access touse this function

Heuristic Evaluation A sample problem (telephone banking)

Heuristic Evaluation Ten usability guidelines from Nielsen (1994)

Visibility of system status Match between system and real world User control and freedom Consistency and standards Error prevention Recognition rather than recall Flexibility and efficiency of use Aesthetic and minimalist design Help users recognize, diagnose, and recover from errors Help and documentation

Heuristic Evaluation Improving usability problem reports (Jeffries 1994)

Describe the problem and the solution separately Provide justifications for the problem and the solution Include an assessment of the severity of the problem Explicitly consider possible trade-offs Evaluate carefully any solution that requires new

functionality to be added to the application Try to look at each problem from multiple levels of

abstraction Examine the problem reports as a collection, replacing local

optimizations and trade-offs with general solutions that fit the application as a whole

Additional Materials SIGCHI

Great Online Library of Resources for Members e.g. Rosenbaum, Rohn, and Homburg.

A Toolkit for Strategic Usability. 2000. CHI Letters.

Additional Materials Brooks, Frederick. “No Silver Bullet”

Our text refers to there being no “silver-bullet” process for designing and evaluating interfaces (p. 73).

This is a reference to Brooks’ paper where he suggests that there will be no order of magnitude improvement in software design (termed "silver bullet") in the next 20 years.

Designing complex systems is inherently difficult.

Additional Materials Cooper, Alan. 1999. The Inmates are

Running the Asylum Engineers are an atypical specimen. Interaction Design must separate itself from

engineering. Engineering roles are concerned with

implementation details while design roles are concerned with user goals.

Activity and Discussion Introduce the activity. Split class into three groups. Give information to groups. Groups work on for approx.

8-10 minutes. Sketch or verbally describe the resulting design.

One person from each group present the design to the class.

Class discussion

Thank You Remember:

The user To evaluate To Iterate Have a nice day!