Past, Present, and Future of Information Visualization

Tiziana Catarci| Sapienza – Università di Roma

Giuseppe Santucci| Sapienza – Università di Roma

Information = “data which serve a purpose”

Where to find it? Is it the right one?

Supply Supplier Part Project Quantity

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Representation of the "Supply" relation with a hypergraph with label node copies

Supply Supplier Part Project Quantity 1 2 5 17 1 3 5 23 2 3 7 9 4 12 23 9 4 6 12 6Tabular representation of the "Supply" relation

Supply Supplier Part Project Quantity

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Representation of the "Supply" relation with a hypergraph without label node copies

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How to manipulate it? How to make sense out of it?

Visual Representations

We call visual representation one based on the use of visual formalisms for communicating relevant concepts.

Visual Representation is a language for the eye, which benefits from the ubiquitous properties of the VISUAL PERCEPTION

"The intricate nature of a variety of computer-related systems and situations can, and in our opinion should, be represented via visual formalisms; visual because they are to be generated, comprehended, and communicated by humans; and formal, because they are to be manipulated, maintained, and analyzed by computers". (D. Harel)

Basic visual formalisms in the DB area: forms, diagrams, and icons.

Using the “Right” Representation

•Certain data visualizations may produce unsound pictures (pictures that express relationships that are not true in the information system)•Some graphical primitives are not adequate for expressing certain types of data (e.g. shape is not adequate for expressing ordered domains)•Interpretation cost (not all graphical primitives that are adequate for encoding certain information are equally effective) • The final goal is to provide general frameworks for automatic (or semi-automatic) generation of correct, complete, and effective visualizations (given any data, users, tasks)

Example

Tow n P eople # P osition Distance

R ome 4, 000, 000 0Milan 1, 800, 000 N orth 600N aples 1, 500, 000 S outh- East 200Pisa 150, 000 N orth- West 350Pes cara 200, 000 East 220

Rome

Naples

Milan

PescaraPisa

Neither correct nor completePisa

350 Km

600 Km

200 Km

220 KmRome

Naples

Milan

>2,000,000

People #

From 1,000,000 to 2,000,000

<500,000

From 500,000 to 1,000,000

Pescara

Complete but not correct

P isa

350 Km

600 Km

200 Km

220 KmRom e

N aples

Milan

> 2,000,000

P eople #

F rom 1,000,000 to 2 ,000,000

< 500,000

F rom 500,000 to 1 ,000,000

P escara

OK!

DARE

General theory for establishing the adequacy of a visual representation, once specified the database characteristics

DARE system, which implements such a theory and works in two modalities

•Representation Check •completeness •correcteness

•Representation Generation•Different kinds of rules:

Visual rules: characterize the different kinds of visual symbols and visual attributes.

Data rules: specify the characteristics of the data model, the database schema, and the database instances.

Mapping rules: specify the link between data and visual elements.

Perceptual rules: tell us how the user perceives a visual symbol, relationships between symbols, and which is the perceptual effect of relevant visual attributes such as color, texture, etc.

An old fashioned demo: DARE

Old fashioned?

• Local application (even if Java based)

• Only two visualization paradigms

• One visualization at time

• Not a clear separation among steps DATA --- > Visualization

• But... It was about early 90s...

Canonical steps of "up to date" Infovis - Representation

Canonical steps of "up to date" Infovis - Presentation REPRESENTASTIOM

Better comprehension of perceptive issues

One (very) simple question

• How many 3s here ?• You have 4 seconds…

458757626808609928083982698028747976296262867897187743671947746588786758967329667287682085

Game over!

So ?

• Time was not enough?

• You can do that in less than 0.2 seconds !

• Let’s try a different visualization…

Pre-attentive data encoding

Interaction is a key issue

FUTURE: Web based , multiple, coordinated views

• Let’s rearrange the rows

Treatments

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Treatments

Crops

Rearrange

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Treatments

A B C D E F G

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Crops10

A D C E G B F

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Treatments

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Rearrange

Treatments

A B C D E F G

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Crops

Rearrange

(10! , VA can help…)

Interaction!

FUTURE: Tight integration with automated analysis

Visual Analytics

One example

Comparing J. London and M. Twain books

User interaction (a non uniform book?)

Interaction

What about the Bible?

VA & IR - Giuseppe Santucci 24

FUTURE: Integration with everyday devices

Demo !

Summarizing

Well understood issues (just apply them)

Interaction

Visual analytics

Web based application

Deep integration with everyday

devices

Thank you!

Questions?