©2001 Southern Illinois University, Edwardsville All rights reserved. Today Thursday CS 321 Human-Computer Interaction Design Elements Completed Reading: ABF Ch.s 10, 11, 13& 14 Ethics Reading: CKR pp. 13 – 40 Please do not read ahead

©2001 Southern Illinois University, Edwardsville All rights reserved. Interesting Interfaces: Multi-touch sensing Sent by Ross Mead

©2001 Southern Illinois University, Edwardsville All rights reserved. Excise Tasks Goal-directed tasks – actions that lead you directly toward reaching the goal Excise tasks – supporting tasks that don’t lead you toward the goal but are necessary to accomplish it. Examples – window management, navigation, confirmation of actions Eliminating excise makes the user more effective

©2001 Southern Illinois University, Edwardsville All rights reserved. Eliminating Excise and Expert Users “Don’t weld on training wheels” Training screens should easily be turned off

©2001 Southern Illinois University, Edwardsville All rights reserved. Eliminating Excise: making intelligent decisions Which com port should I choose?

©2001 Southern Illinois University, Edwardsville All rights reserved. Eliminating Excise: Halting Interruptions Don’t stop the proceeding with idiocy Non-essential messages, confirmation dialogs, error messages that users can’t deal with or don’t care about.

©2001 Southern Illinois University, Edwardsville All rights reserved. Navigation Any action that takes the user to a new part of the interface or which requires him/her to locate objects, tools. Or data. Poor navigation is a critical obstacle to usability Common types of navigation Between multiple windows or screens Between panes in a window Between tools or menus Within information displayed in a frame, such as scrolling

©2001 Southern Illinois University, Edwardsville All rights reserved. Navigation between multiple windows Gross shifting of attention Context switch overhead – disrupts flow Additional windows management Sovereign posture – single window/multiple panes

©2001 Southern Illinois University, Edwardsville All rights reserved. Navigating between multiple panes Too many panes can cause visual clutter and confusion More scrolling Minimize panes, possibly use tabs

©2001 Southern Illinois University, Edwardsville All rights reserved. Navigating between tools and menus Spatial organization in a pane or window is critical to reducing extraneous mouse movements Annoying Fatigue RSI’s Reserve menus for rare items Group related tools

©2001 Southern Illinois University, Edwardsville All rights reserved. Improving Navigation Sign posts – persistent objects that serve as a reference point

©2001 Southern Illinois University, Edwardsville All rights reserved. Improving Navigation Provide appropriate mapping of controls

©2001 Southern Illinois University, Edwardsville All rights reserved. Inflecting Navigation Organization of an interface so that typically used functionality is made most conveniently accessible Frequency of use Degree of dislocation Degree of exposure Users make commensurate effort if the rewards justify it.

©2001 Southern Illinois University, Edwardsville All rights reserved. Could an HCI Specialist have prevented the 2000 Election Problems? Palm Beach County Poll Butterfly Ballot Why did the Florida Residents have such a difficult time using the Voto-matic Voting Machines?

©2001 Southern Illinois University, Edwardsville All rights reserved. What is a Chad? Hanging Chad: Two or Three Corner Pregnant Chad

©2001 Southern Illinois University, Edwardsville All rights reserved. Could an HCI Specialist have prevented the 2000 Election Problems? Affordance – perceived properties of an artifact Visibility – make apparent to users the actions they are allowed to take Constraints – factors that encourage proper actions and prevent erroneous ones Feedback – provides information about the effects of users’ actions Prototype Testing Palm Beach County Poll Butterfly Ballot

©2001 Southern Illinois University, Edwardsville All rights reserved. Actual Paper Prototype

©2001 Southern Illinois University, Edwardsville All rights reserved. Actual Paper Prototype

©2001 Southern Illinois University, Edwardsville All rights reserved. Actual Ballot

©2001 Southern Illinois University, Edwardsville All rights reserved.

Could an HCI Specialist have prevented the 2000 Election Problems? Internal consistency – are the elements within the interface coherent? Organization – is the screen well laid out with proper use of white space? How is the balance? Is it cluttered causing cognitive overload? Grouping – are the elements logically or haphazardly placed around the screen? Are they appropriately grouped? Are grouping aides such as alignment, borders, and Gestalt Principles properly used? Palm Beach County Poll Butterfly Ballot

©2001 Southern Illinois University, Edwardsville All rights reserved. Could an HCI Specialist have prevented the 2000 Election Problems? Hierarchy – Are the critical elements emphasized over the non- critical ones? Simplicity – Excess or extra items that serve as distractions? Legibility / Readability – Good choice of font and font size? Good use of white space? Innovation – Did it benefit the voters or the candidates? Palm Beach County Poll Butterfly Ballot

©2001 Southern Illinois University, Edwardsville All rights reserved. Could an HCI Specialist have prevented the 2000 Election Problems? I can tell you, regular people get tripped up by the simplest things. It is sobering to observe a test where a user repeatedly asks "How do I go to the next step?" and you want to scream "Click the 'Next' button!" that they just somehow can't see. You thought the button was obvious, but, as anyone who's missed a highway exit learns, in the real world what's obvious to one person who knows the answer is not always obvious to a newcomer. People who are making fun of the voters who made mistakes should think about the obvious mistakes they've made in their lives. If "most people" never have problems doing simple things why were there so many flashing 12:00s on old VCRs? Would usability testing (which often only uses 5-20 people of each background) have caught it? I think so. Dan Bricklin, Designer of VisiCalc and other widely used programs

©2001 Southern Illinois University, Edwardsville All rights reserved. Voting Machine Design

©2001 Southern Illinois University, Edwardsville All rights reserved.