CSC 8570 -- USICSC 8570 -- USI

Class Meeting 3Class Meeting 3

September 12, 2007September 12, 2007

Homework for TodayHomework for Today

Research team membership Research team membership – FinishedFinished

Research areasResearch areas– Comments sentComments sent

GOMS analysisGOMS analysis– Hand inHand in

Creating TablesCreating Tables

Concerns:Concerns: 7 of 14 tables didn’t follow 7 of 14 tables didn’t follow

specifications and example rowspecifications and example row Several examples of header row (not Several examples of header row (not

required by specs) poorly formatted required by specs) poorly formatted or with less helpful labelsor with less helpful labels

Interacting with the InterfaceInteracting with the Interface

Issues are:Issues are: Types of interface widgetsTypes of interface widgets Methods of interactionMethods of interaction Formal notation for interactionsFormal notation for interactions Extensions to the Keystroke Level ModelExtensions to the Keystroke Level Model Timings for each simple interactionTimings for each simple interaction Interactions for control vs. for contentInteractions for control vs. for content QuasimodesQuasimodes Others?Others?

Interface ExamplesInterface Examples

Focus on battery operated devices on our Focus on battery operated devices on our first week’s list and other small interfacesfirst week’s list and other small interfaces– Remote car lock controlRemote car lock control– WatchWatch– Cell phoneCell phone– IPodIPod– Laptop computerLaptop computer– PDAPDA– Programmable thermostatProgrammable thermostat– Simple calculatorSimple calculator

Interface Examples (2)Interface Examples (2)

NotationNotation

How should we describe interactions How should we describe interactions with (or actions taken with) the with (or actions taken with) the interface devices?interface devices?

Time for some discovery groupsTime for some discovery groups

Group WorkGroup Work

Pair up by threes, except one pair of two.Pair up by threes, except one pair of two. Create a list of simple (atomic?) widgets Create a list of simple (atomic?) widgets

that appear in interfaces. Consult the list that appear in interfaces. Consult the list of examples, generalize, then synthesize.of examples, generalize, then synthesize.

For each item on the list, state the actions For each item on the list, state the actions that can be performed on it.that can be performed on it.

Suggest a notation for each action Suggest a notation for each action expressed in a way that it is easy to form a expressed in a way that it is easy to form a sequence of actions.sequence of actions.

Group Work (2)Group Work (2)

Notes:Notes: Distinguish between physical devices Distinguish between physical devices

and actions on them and interface and actions on them and interface widgets and actions on them. Both widgets and actions on them. Both types should be on your list.types should be on your list.

Group Work SummaryGroup Work Summary

Construct the union table of widgets Construct the union table of widgets and actions on them.and actions on them.

Invent the formal notation for Invent the formal notation for describing the actions.describing the actions.

Create some examples of performing Create some examples of performing tasks using these widgets, tasks using these widgets, expressing the method in the formal expressing the method in the formal notation.notation.

Interface WidgetsInterface Widgets

Physical devicesPhysical devices– KeyboardKeyboard– Graphical Interface Device (GID)Graphical Interface Device (GID)

Point, buttonsPoint, buttons

– Touch padTouch padGestures, point, tapGestures, point, tap

Virtual devicesVirtual devices– Programmed as objects and methodsProgrammed as objects and methods– SummarySummary

Interface Widgets (2)Interface Widgets (2)

The The linkedlinked chart shows the summary chart shows the summary of the group work.of the group work.

The chart will be revised asThe chart will be revised as– new widgets are created or discoverednew widgets are created or discovered– new actions are needednew actions are needed– new notation is invented new notation is invented

Interface ModelsInterface Models

Look at:Look at: Physical interfacePhysical interface Operations of physical interfaceOperations of physical interface Task setTask set Error costError cost

Error CostError Cost

Definition:Definition: The cost, measured in The cost, measured in time or keystroke level actions, time or keystroke level actions, needed to recover from an erroneous needed to recover from an erroneous action with a widget.action with a widget.

Example: Example: Mistyping “the” as “teh”. Mistyping “the” as “teh”. Error cost is four keystrokes: 2 Error cost is four keystrokes: 2 backspace and 2 for the correct keys.backspace and 2 for the correct keys.

Models of Physical ActionModels of Physical Action

Fitts’ Law: moving a cursor to a Fitts’ Law: moving a cursor to a targettarget

Keystroke Level (Card & Moran): Keystroke Level (Card & Moran): timing predictions for a task timing predictions for a task represented as a sequence of represented as a sequence of “physical” operations“physical” operations

Hick’s Law: time for choosing among Hick’s Law: time for choosing among a number of widgetsa number of widgets

Fitts’ Law QuestionsFitts’ Law Questions

How does Fitts’ Law generalize to 2-How does Fitts’ Law generalize to 2-dimensional targets?dimensional targets?– Where does the user aim?Where does the user aim?– Where does the user land?Where does the user land?– What path is followed?What path is followed?– What happens with partially hidden What happens with partially hidden

targets?targets?

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

GOMSGOMS

Example:Example:– Goal: Goal: Selecting an item from a menuSelecting an item from a menu– Method: Method:

Find menu headingFind menu headingPoint cursor at menu headingPoint cursor at menu headingClick “mouse” button (displaying menu Click “mouse” button (displaying menu

entries)entries)Find desired entryFind desired entryPoint cursor atPoint cursor at menu entrymenu entryClick “mouse” button (choosing menu option)Click “mouse” button (choosing menu option)

GOMS (2)GOMS (2)

Assume that you manage your email Assume that you manage your email messages using a hierarchy of messages using a hierarchy of folders that is at least five levels folders that is at least five levels deep. Develop a GOMS analysis for deep. Develop a GOMS analysis for deleting a message in a level three deleting a message in a level three folder when you currently are folder when you currently are reading messages in your inbox (a reading messages in your inbox (a level one folder). level one folder).

GOMS (3)GOMS (3)

Goal:Goal: Operators:Operators: Methods:Methods: Selection rule:Selection rule:

Research ProjectResearch Project

Teams (done)Teams (done) Areas (should be narrowed, can be Areas (should be narrowed, can be

revised)revised) HypothesisHypothesis Independent variablesIndependent variables Dependent variablesDependent variables

Research Project (2)Research Project (2)

SourcesSources– ACM Digital LibraryACM Digital Library– Science Citation IndexScience Citation Index– Web, but be carefulWeb, but be careful– Conference proceedings, MSC 159Conference proceedings, MSC 159

BibliographyBibliography– Entered into EndNoteEntered into EndNote

Research Project (3)Research Project (3)

IRBIRB Form Form– Consent formConsent form

Research Project (4)Research Project (4)

Experimental designExperimental design– Between subjectsBetween subjects– Within subjectsWithin subjects

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

Next TimeNext Time

Research project activitiesResearch project activities Create a GOMS model for Create a GOMS model for

constructing the table of sums of constructing the table of sums of powers of 2. The method must be at powers of 2. The method must be at the keystroke level and include the the keystroke level and include the 45 keystrokes necessary to enter the 45 keystrokes necessary to enter the data.data.

Next Time (2)Next Time (2)

Research projectResearch project– Submit hypothesis, independent Submit hypothesis, independent

variables, dependent variablesvariables, dependent variables– Submit draft of IRB formSubmit draft of IRB form– Submit bibliography as printed from Submit bibliography as printed from

EndNoteEndNote

The Future of HCIThe Future of HCI

John Canny, The Future of HCI, from John Canny, The Future of HCI, from HCIHCI, , 44(2006), July/August(2006), July/August

Do Canny’s views match our ideas?Do Canny’s views match our ideas? What did he miss?What did he miss? What did we miss?What did we miss?

Research Team MeetingsResearch Team Meetings