CSC 8570 -- USICSC 8570 -- USI

Class Meeting 4Class Meeting 4

September 13, 2006September 13, 2006

Notations for ActionsNotations for Actions

Actions for a keyboard and graphical input Actions for a keyboard and graphical input device (GID) include:device (GID) include:

Tap: pressing and immediately releasing a Tap: pressing and immediately releasing a key. Implemented with a momentary key. Implemented with a momentary contact (spring-loaded) switch.contact (spring-loaded) switch.

Click: Position the GID and tap the GID Click: Position the GID and tap the GID button.button.

Double click: Position the GID and tap the Double click: Position the GID and tap the GID button twice quickly, without GID button twice quickly, without repositioning.repositioning.

Notation for Actions (2)Notation for Actions (2)

Keystroke Level ModelKeystroke Level Model– K[ ], a keystroke. E.g. K[b] means K[ ], a keystroke. E.g. K[b] means

tapping lower case btapping lower case b– P, pointing. E.g. positioning the GIDP, pointing. E.g. positioning the GID– H, homing. E.g. moving from keyboard H, homing. E.g. moving from keyboard

to GID or GID to keyboardto GID or GID to keyboard– M, mental processingM, mental processing– R, respondingR, responding

Notations for Action (3)Notations for Action (3)

What does the descriptionWhat does the description

To create a right justified paragraph, To create a right justified paragraph, use Control + .use Control + .

ask you to do?ask you to do?

Notations for Action (4)Notations for Action (4)

More actions:More actions: Press and hold a keyPress and hold a key Release a keyRelease a key

– But on what signal or input?But on what signal or input?

Notations and Actions (5)Notations and Actions (5)

Raskin/BeckRaskin/Beck– Press and hold: Press and hold: bb– Release: Release: bb– Tap: Tap: bbbb, shortened to , shortened to bb or just or just bb– Release on signal: Release on signal: bb[ ][ ]– Note that key names are italicizedNote that key names are italicized

Examples:Examples:– Create an upper case M: Create an upper case M:

ShiftShiftmmmmShiftShift, shortened to , shortened to ShiftShiftmm

Notations for Action (6)Notations for Action (6)

Examples (continued)Examples (continued)– Distinguish between Distinguish between EnterEnter and and E n t e r E n t e r

EnterEnter is the name of a key and is the name of a key and E n t e r E n t e r is short for is short for EEnntteerr

– bb[20] gives a string of [20] gives a string of bbss– CtrlCtrlAltAltDelDelbrings up the Task brings up the Task

ManagerManager

Clock SettingClock Setting

Set the clock one hour earlier, the Set the clock one hour earlier, the common action at the end of daylight common action at the end of daylight savings time.savings time.

GOMS modelGOMS model– Goal: Goal: stated abovestated above– Operations:Operations:– Methods:Methods:– Selection Rule:Selection Rule:

Bad InterfacesBad Interfaces

Detectable with GOMS model?Detectable with GOMS model?

Interfaces and WidgetsInterfaces and Widgets

What can a user do? When? Where?What can a user do? When? Where?

How effectively?How effectively?

Catalog of interface actionsCatalog of interface actions Catalog of interface widgetsCatalog of interface widgets

Modeling ActionsModeling Actions

Task analysis: temporal issuesTask analysis: temporal issues GOMS analysis: method issuesGOMS analysis: method issues Keystroke level: operator issuesKeystroke level: operator issues

Task AnalysisTask Analysis

Describes the process the user Describes the process the user chooses to reach a goal in a specific chooses to reach a goal in a specific domaindomain

Hierarchical description, typicallyHierarchical description, typically Task modeling systemsTask modeling systems

– GOMS (?)GOMS (?)– ConcurTaskTreesConcurTaskTrees– UAN (User Action Notation)UAN (User Action Notation)

Research ProjectResearch Project

Hypotheses Hypotheses (tonight)(tonight) Independent variables Independent variables (tonight)(tonight) Dependent variables Dependent variables (tonight)(tonight) Bibliography Bibliography (next week)(next week) Background Background Formal setting Formal setting (let’s talk)(let’s talk)

Theory CollectionTheory Collection

Visual processingVisual processing Three-stage visual systemThree-stage visual system Preattentive processing theoryPreattentive processing theory Structured object perception theory Structured object perception theory

(Biederman)(Biederman) Scientific color theory (CIE)Scientific color theory (CIE)

Theory Collection (2)Theory Collection (2)

Motor Behavior ModelsMotor Behavior Models Hick-Hyman Law: choice timeHick-Hyman Law: choice time Keystroke-Level Model: error-free Keystroke-Level Model: error-free

task completion timetask completion time Three-state model of graphical input Three-state model of graphical input

(Buxton)(Buxton) Fitts’ Law: human movementFitts’ Law: human movement Guiard’s Model of Bimanual SkillGuiard’s Model of Bimanual Skill

Theory Collection (3)Theory Collection (3)

Task analysisTask analysis Hierarchical model using Hierarchical model using

ConcurTaskTreesConcurTaskTrees

Research Project (2)Research Project (2)

Experimental designExperimental design– Between subjectsBetween subjects– Within subjectsWithin subjects

Sources of biasSources of bias Sources of subjectsSources of subjects Logic of conclusionsLogic of conclusions

Research Project (3)Research Project (3)

Institutional Review Board (IRB)Institutional Review Board (IRB) IRB form IRB form Informed consentInformed consent

Research Project (4)Research Project (4)

Short presentationShort presentation– One spokespersonOne spokesperson– Five minutesFive minutes– Hypothesis, variables, initial Hypothesis, variables, initial

experimental designexperimental design– PowerPoint or transparenciesPowerPoint or transparencies

Next TimeNext Time

Read Carroll, Chapter 6. Note that this Read Carroll, Chapter 6. Note that this chapter describes several “spaces.”chapter describes several “spaces.”

Create a concept map that shows the Create a concept map that shows the relationships between these “spaces.” Make relationships between these “spaces.” Make sure your map is labeled with your name so sure your map is labeled with your name so that it can be submitted.that it can be submitted.

Submit a revised IRB form and bibliography.Submit a revised IRB form and bibliography. Research project presentationResearch project presentation

Research Team MeetingsResearch Team Meetings