human-information interaction · importance of sensemaking x75% of “significant tasks” on the...

stanford hci group / cs147

http://cs147.stanford.edu06 November 2007

Human-Information Interaction

Scott Klemmertas: Marcello Bastea-Forte, Joel Brandt,Neil Patel, Leslie Wu, Mike Cammarano

Questions about the Project

Engelbart Video

Form Me to You

ADAPTIVE BEHAVIOR107 (months) SOCIAL Social Behavior106 (weeks)105 (days)104 (hours) RATIONAL Adaptive Behavior

103

102 (minutes)101 COGNITIVE Immediate Behavior100 (seconds)10-1

10-2 BIOLOGICAL 10-3 (msec)10-4

MegStewart

HUMAN INFORMATION INTERACTION

GOMS

Routine cognitive skillWell-known path

Information Search

Problem solvingHeuristic searchExponential if don’t know what to do

OPTIMALITY THEORYInformationEnergy

MaxUseful info

TimeMaxEnergyTime [ ][ ]

Optimal Foraging Theory Information Foraging Theory

Information Foraging Theory:

patchWithinpatchBetweenWB TTGain

TTGR

−− +=

+=

Microeconomics of information access.

People are information rate maximizers of benefits/costsInformation has a cost structure

Desk DeskShelf

Computer

ActiveProjectPiles

ReferenceArea

INFORMATION PATCHES

e.g. desk piles,Alta vista search list

unlike animalsforaging for food, humans can do patch construction

We’ll stay in a patch longer…

When a patch is highly profitableAs distance between patches increasesWhen the environment as a whole is less profitable

WITHIN-PATCH ENRICHMENT:

INFORMATION SCENT

perception of value and cost of a path to a source based on proximal cues

Relevance-Enhanced Thumbnails Within-patch

enrichmentEmphasize text that is relevant to query

Text callouts

020406080

100120140160180

Picture Homepage E-commerce Side-effects

Tot

al S

earc

h T

ime

(s)

Text Plain Enhanced

Allison Woodruff

PHASE TRANSITION IN NAVIGATION COSTS AS FUNCTION OF INFORMATION SCENT

Notes: Average branching factor = 10Depth = 10

0 2 4 6 8 100

50

100

150

Depth

Num

ber o

f pag

es v

isite

d

.100

.125

.150

0 2 4 6 8 100

50

100

150

.100

.150

Probability of choosing wrong link (f)

0 0.05 0.1 0.15 0.20

20

40

60

80

100

f

Num

ber o

f Pag

es V

isite

d pe

r Lev

el

Linear Exponential

IMPORTANCE FOR WEB DESIGN

Jarad Spool, UIE

Peter Pirolli

MACHINE MODELING OF INFORMATION SCENT

cell

patient

dose

beam

new

medical

treatments

procedures

InformationGoal Link Text

PREDICTION OF LINK CHOICER2 = 0.72

0

5

10

15

20

25

30

35

0 5 10 15 20 25 30 35Observed frequency

Pred

icte

d fr

eque

ncy

R2 = 0.90

0

10

20

30

40

50

0 10 20 30 40 50Observed frequency

Pred

icte

d fr

eque

ncy(a) ParcWeb (b) Yahoo

USER FLOW MODEL

Flow users through the network

User need (vector of goal concepts)

Determine relevance of documents

.5.3

.2

Calculate Pr(Link Choice) for each page Examine user patternsStart users at page

SENSE MAKING TASKSCharacteristics

Massive amounts of dataIll-structured taskOrganization, interpretation, insight neededOutput, decision, solution required

ExamplesUnderstanding a health problem and making a medical decisionBuying a new laptopWeather forecastingProducing an intelligence report

Importance of Sensemaking75% of “significant tasks” on the Web are more than simple “finding” of information (Morrison et al., 2001)

Understanding a topic (e.g., about health)Comparing/choosing products

Information retrieval does not support these tasks (Bhavnani et al., 2002)

E.g., Estimated that one must visit 25 Web pages in order to read about 12 basic concepts about skin cancer

SENSEMAKING

SHOEBOX

EVIDENCE FILE

Search & Filter

Read & Extract

Schematize

Build Case

Tell Story

Search for Information

Search for Relations

Search for Evidence

Search for Support

Reevaluate

TIME or EFFORT

STRU

CTUR

E

SCHEMAS

HYPOTHESES

PRESENTATION

EXTERNAL DATA

SOURCES

SENSEMAKING

SHOEBOX

EVIDENCE FILE

Search & Filter

Read & Extract

Schematize

Build Case

Tell Story

Search for Information

Search for Relations

Search for Evidence

Search for Support

Reevaluate

TIME or EFFORT

STRU

CTUR

E

SCHEMAS

HYPOTHESES

PRESENTATION

EXTERNAL DATA

SOURCES

Sensemaking Loop

Foraging Loop

Credits & Further Reading

This lecture draws heavily on Stu Card’s slides on HIIPeter Pirolli, Information Foraging