The Zen of Visual Analysisof Visual Analysis

Chris StolteVice President, Engineering & co-founder

How do people reason about data?

The Cycle of Visual Analysisy y

2008 Presidential ElectionC i E ditCampaign Expenditures

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Not just

“Ah !”“Aha!”

advice:advice:Iterate, explore, andpexperiment

dl f t k…regardless of task

How can products supportHow can products support“being one with your data”

…and how can I use them effectively?

How can products supportHow can products support“being one with your data”

…and how can I use them effectively?

S pport the“C cle of Vis al Anal sis”Support the“Cycle of Visual Analysis”

Supporting the “Cycle of Visual Analysis”pp g y y

IncrementalIncrementalExpressivepUnifiedDirect

Supporting the “Cycle of Visual Analysis”:

Incremental

Allow people to easily and incrementally change the datathey are looking at and how they are looking at it

click click

advice:

Start simple…

Supporting the “Cycle of Visual Analysis”:

Expressive

There is no single view for ll k d ll dall tasks and all data

Supporting the “Cycle of Visual Analysis”:

Expressive

advice:advice:Reverse your thinking – start with the data

Supporting the “Cycle of Visual Analysis”:

Unification with the database

Query many times and then generate a summary graph.

Traditional Reporting Tools

versus

Traditional Reporting Tools

Iteratively change the data and image to find the perfect view.

TableauQuery once and then iterate on the presentation of the data.

Traditional Visualization Tools

Supporting the “Cycle of Visual Analysis”:

Unification with the database

Leverage the advances inLeverage the advances in fast database technology

Supporting the “Cycle of Visual Analysis”:

Direct Interaction

Make the tool disappear.Allow the user to directly interact 

with the data.

How is this possible? p

VizQLImagine if databases shipped with only 5 prebuilt querieswith only 5 prebuilt queries

How can products supportHow can products support“being one with your data”

…and how can I use them effectively?

Generate Effecti e Vie s of DataGenerate Effective Views of Data

l h ld ’ h b

Generating Effective Views of DataPeople shouldn’t have to be 

graphic designers or psychologists

Generating Effective Views of Data

An effective presentation of data:

ll f h d– Communicates all of the data– Communicates only the data– Leverages the human perceptual system

– Is understandable– Is interpretable

ll f l t d tGenerating Effective Views of Data

Communicate all of relevant data

Bad Bad Good

l th d tGenerating Effective Views of Data

Communicate only the data

Bad Bad

L th

Generating Effective Views of Data

Leverages thehuman perceptual system

Bad Good

Generating Effective Views of Data

Isunderstandableunderstandable

advice:advice:Keep your visuals simple

Generating Effective Views of Data

Isinterpretablep

advice:advice:Annotate but remain focusedremain focused

Generating Effective Views of Data

How does Tableau support generating effective views of data?

Limiting the visual properties to a small and proven set

Great defaults

Small multiples

Show Me and Show Me Alternatives

Titling, captioning, and annotationg, p g,

Generating Effective Views of Data

How does Tableau support generating effective presentations?

Limiting the visual properties to a small and proven set

Great defaults

Small multiples

Show Me and Show Me Alternatives

Titling, captioning, and annotationg, p g,

Generating Effective Views of Data

How do you pick effective colors?

A “line” in HSV corresponds closely to a set of perceptually p p yequivalent colors…but not quite. There is no good programmatic way to pick the colors so we hired a color expert to manually pick colors.

Generating Effective Views of Data

To encode unordered data, we vary colors primarily in hue:, y p y

To encode numeric or ordered data we vary primarily in saturation and value:To encode numeric or ordered data, we vary primarily in saturation and value:

We discourage the use of more than 20 colors.g

Pick colors that can be named so people can talk about them “ that point the cyan‐pinkish orange in the upper corner ”…that point…the cyan pinkish orange in the upper corner…

We consider color blindness.

Compare to Excel XP:

Generating Effective Views of Data

C l f communicating dataColor for communicating data

Color for aestheticsColor for aesthetics

Generating Effective Views of Data

Automatic marks picks the best mark based on properties of the data.

Generating Effective Views of Data

It is only possible to encode a limited number of dimensions in properties such as color, size, and shape.

advice:advice:Use small multiples to simply and effectively see more datasee more data

How can products supportHow can products support“being one with your data”

…and how can I use them effectively?

Be Eas and Simple to UseBe Easy and Simple to Use

Be easy and simple to use

What do people mean when they say “easy to use”?

LearnableIntuitiveEfficientDirect

Measuring ease of use is difficult:

lA chart wizard is easy to learn and yet inefficient and hard to use.

Be easy and simple to use

How do we achieve ease of use?

Allowing incremental interaction

Being direct

Providing freedom

Knowing and respecting our user

Being simpleBeing simple

Be easy and simple to use

Provide freedom

No templatesNo templates, no six‐month IT projects,  

no modesno modes,no wizards

Ask questions of your data – and get answers!

advice:Empower

diyour audience –share interactive viewsviews

Be easy and simple to use

Know and respect the user

Focus the user interface on the contentFocus the user interface on the content

Support the user’s task

All th t t i t i t t d flAllow the user to get into an uninterrupted flow

Provide great defaults

E l

Be easy and simple to useExamples:

A single toolbar with a limited set of muted buttons.Minimizing the non‐data ink.Unsaturated colors for the interface, saturated colors for the data.

the user’s data

d iadvice:Stay focusedStay focused on the data

How can products supportHow can products support“being one with your data”

…and how can I use them effectively?

Generate Bea tif l Res ltsGenerate Beautiful Results

Generating Beautiful Results

Who can Visual Analysis help?y p

Everybody with data that is not getting answers

advice:advice:Don’t limit yourself tolarge data orspecial projectsspecial projects

advice:SeekSeek outside inspiration

SummaryyIterate, explore, and experiment regardless of task

Start simpleStart simple

Reverse your thinking and start with the data

Keep o r is als simpleKeep your visuals simple

Annotate but remain focused

Use small multiples

Empower your audience by sharing interactive views

Stay focused on the data

Don’t limit yourself to large data

Seek outside inspiration