Interaction Styles

Hall of Fame The 3-point seatbelt Brief history ●1959: Invented by Nils Bohlin ○patent released by Volvo ○saving lives > profit ●1968 (and on): required on all American cars ●2002: Bohlin died ○Volvo estimated 1 million+ lives saved ●2012: NHTSA estimated 12,174 lives saved (US) (ages 5+) ○raising annually Ryan McDermott

What makes it work? Understanding o belt keeps your body secure o slack locks out when force is exerted on belt ● history/three-point-seatbelt-inventor-nils-bohlin- bornhttp:// history/three-point-seatbelt-inventor-nils-bohlin- born ● Ryan McDermott Industrial Design o secures upper and lower body at hips, as opposed to abdomen o “Immovable anchorage point” – Bohlin o one simple movement Discoverability o Seat belt affords pulling o Seat buckle affords inserting something shaped like the buckle tongue) o Seat buckle affords pushing (for release) o Pulling seatbelt gives feedback (stops giving slack)

PS4 Buttons Hall of Shame Weston Miller

By zooming in, changing the angle AND changing the lighting…

Affordances They are “Buttons”, but they don’t “push” in. Consistency More like a touch screen than the previous PS consoles. Constraint Buttons can only be touched. Feedback Lights turn on when the power button is touched. If eject button is pressed, the disc is ejected (if there is one in the system) Mapping Both buttons are by disc slot and are directly across from the other with the slot in the middle. User has to memorize that the top is power and the bottom is eject or run the risk of accidentally turning the system off instead. Visibility They blend in with the line going all the way around making it difficult to guess they are there without close inspection The symbols are small. Also, when the lights are on and it’s dark in the room, the symbols are almost invisible.

Objectives for today Revisit “working in groups” Get a quick tour of interaction styles

Working in groups: reminders Different people have different communication styles Capture ideas on paper; discuss the ideas, not the person Ask questions, propose alternatives; be cautious about definitive statements Be open and honest Put it in writing –Who is responsible for what; when is it due Be aware that there are different ways to contribute –Not everyone needs to program –Not everyone needs to go on each user visit Not just the end result matters – the process does, too

Design: A Broad Spectrum System Design –Requirements Information Design Graphic Design Interaction Design

Interaction Design Styles Menu Selection Form fill-in Direct Manipulation Command language Natural Language

Menu Selection Users read a list of items Select the item most appropriate Observe the effect Early on, the way most systems worked. We had moved away from it a little (what’s coming) but it has made a revival with the web

Menu Selection

Advantages Shortens learning Reduces keystrokes Structures decision making Permits use of dialog management Easy error handling Disadvantages Presents danger of many menus May slow frequent users Consumes screen space Requires rapid display

Form Fill-in Used when data entry is required Users see a display of related fields and enter data in each field as appropriate Note: very common on the web

Form Fill-in

Form fill-in Advantages Simplifies data entry Requires modest training Gives convenient assistance Permits form management tools Disadvantages Consumes screen space

Direct Manipulation Create a visual representation of the world of action where users can directly make changes and see results

Direct Manipulation Search

Zillow Online demo at –

Direct Manipulation Advantages Visually presents task concepts Allows easy learning Allows easy retention Can prevent errors Encourages exploration High subjective satisfaction Disadvantages Harder to program Require graphics display and pointing device

Command Language For frequent users Must learn the syntax and options

java command

Command Language Advantages Flexible Appeals to ‘power users’ Supports user initiative Allows convenient creation of macros Disadvantages Poor error handling Substantial training and memorization

Natural Language Researchers have been working for years in the hope that computers can be made to respond to arbitrary sentences Note: may work with or without speech recognition

Natural Language Advantages Relieves burden of learning syntax May be “natural” in some settings, e.g., interaction over a telephone Disadvantages Requires clarification dialog May require more keystrokes May not show context Is unpredictable

Some comments All these styles should be in your toolbox (well, maybe not NL) They may be combined in a single app –Direct Manipulation with menus and forms is common Different platforms / toolkits make particular styles more or less easy –We’ll talk about toolkits some next week