2. The
Hairball:
A
Metaphor
for
Complexity
h6p://www.nd.edu/~networks/PublicaBon%20Categories/01%20Review%20ArBcles/ScaleFree_ScienBfic%20Ameri%20288,%2060-‐69%20(2003).pdf
4. Release by Joint Economic Committee minority Republicans led by Boehner
(2010), Iliinsky & Steele fig 4-14
Neither Exploratory Nor Explanatory:
Political.
4
5. Redesign by Robert Palmer
(Iliisnky & Steele fig 4-15)
“By releasing your chart, instead of meaningfully
educating the public, you willfully obfuscated an already
complicated proposal.There is no simple proposal to
solve this problem.You instead chose to shout
‘12! 16! 37! 9! 24!’ while we were trying to count
something.”
5
6. Why
Care
About
Networks?
• Epidemiology
• Trees/networks
in
biology
• Clustering
/
recommendaBon
systems
• “Social
network”
so^ware
• Community
design:
online
and
off
• OrganizaBonal
Design
• Computer
networks,
phone
networks,
banks…
• Another
vis
method
-‐
for
relaBonal
data.
6
7. WHAT
IS
A
NETWORK?
It’s
not
a
visualizaBon.
Think
of
it
as
a
data
structure.
8. Data
relaBonship:
enBBes
+
relaBonships
to
other
objects
(node/edge,
vertex/link)
Nodes
and
Edges
may
have
a6ributes,
eg.
gender,
age,
weight,
tv
prefs
connecBon
date,
frequency
of
contact,
type
of
exchange,
direcBonality
of
relaBonship
a6ributes
may
be
calculated
from
network
relaBons
too
9. A
quick
look
at
some
data…
h6ps://marketplace.gephi.org/plugin/excel-‐csv-‐converter-‐to-‐network/
12. 12
It’s
a
natural
human
trait
to
see
visual
similarity
and
proximity
as
meaningful.
Be
very
careful
about
your
display
choices
and
layout
methods!
13. Reading
a
network
visualizaBon
Look at this outlier case!
There’s obviously
something important
going on here,
structurally....
A ménage à
trois over here
MIS?
Using
a
“random”
Gephi
layout
on
the
dolphins
Random!
14. SIMPLE
CALCULATIONS
ON
NETWORKS
CAN
TELL
YOU
LOADS
O^en
you
need
to
visualize
the
structure/role
of
the
graph
elements
as
part
of
the
visualizaBon:
So,
do
some
simple
math.
15. Degree
(In,
Out)
“Degree”
is
a
measure
of
the
edges
in
(directed),
out
(directed),
or
total
(in
directed
or
undirected
graphs)
to
a
node
“Hub”
nodes
have
high
in-‐degree.
In
scale-‐free
networks,
we
see
preferenBal
a6achment
to
the
popular
kids.
h6p://mlg.ucd.ie/files/summer/tutorial.pdf
16. The
Threat
of
Hub-‐Loss
Albert-‐László
Barabási
and
Eric
Bonabeau,
Scale-‐Free
Networks,
2003.h6p://www.scienBficamerican.com/arBcle.cfm?id=scale-‐free-‐
networks
17. VisualizaBon
Aside:
If
Some
Names
are
Huge,
the
Others
are
Invisible-‐?
17
Gephi
Panel
CorrecBng
for
text
size
by
degree
display
issue
18. Betweenness
A
measure
of
connectedness
between
(sub)components
of
the
graph
“Betweenness
centrality
thus
tends
to
pick
out
boundary
individuals
who
play
the
role
of
brokers
between
communiBes.”
h6p://en.wikipedia.org/wiki/Centrality#Betweenness_centrality
Lusseau
and
Newman.
h6p://www.ncbi.nlm.nih.gov/pmc/arBcles/
PMC1810112/pdf/15801609.pdf
19. 19
? This one?
Sized
by
Betweenness
Judging
By
Eye
Will
Probably
Be
Wrong...
Even
be6er,
download
the
stats
and
look
at
them
yourself.
20. Eigenvector
Centrality
IntuiBon:
A
node
is
important
if
it
is
connected
to
other
important
nodes
A
node
with
a
small
number
of
influenBal
contacts
may
outrank
one
with
a
larger
number
of
mediocre
contacts
h6p://mlg.ucd.ie/files/summer/tutorial.pdf h6p://demonstraBons.wolfram.com/NetworkCentralityUsingEigenvectors/
22. Community
DetecBon
Algorithms
E.g.,
the
Louvain
method,
in
Gephi
as
“Modularity.”
Many
layout
algorithms
help
you
intuit
these
structures,
but
don’t
rely
on
percepBon
of
layout!
h6p://en.wikipedia.org/wiki/File:Network_Community_Structure.png
23. You
can
even
do
it
in
your
browser
now…
23
http://bl.ocks.org/john-guerra/ecdde32ab4ad91a1a240
24. CitaBon:
Lusseau
D
(2007)
Why
Are
Male
Social
RelaBonships
Complex
in
the
Doubxul
Sound
Bo6lenose
Dolphin
PopulaBon?.
PLoS
ONE
2(4):
e348.
doi:10.1371/journal.pone.0000348
25. IdenBfying
the
role
that
animals
play
in
their
social
networks
(2004)
D
Lusseau,
MEJ
Newman
Proceedings
of
the
Royal
Society
of
London.
Series
B:
Biological
Sciences
26. Eduarda
Mendes
Rodrigues,
Natasa
Milic-‐Frayling,
Marc
Smith,
Ben
Shneiderman,
Derek
Hansen,
Group-‐in-‐a-‐box
Layout
for
MulB-‐
faceted
Analysis
of
CommuniBes.
IEEE
Third
InternaBonal
Conference
on
Social
CompuBng,
October
9-‐11,
2011.
Boston,
MA
NodeXL
excel
plugin
49. Sample
Layout
Plugins
in
Gephi
h6ps://gephi.org/tutorials/gephi-‐tutorial-‐layouts.pdf
50. Gephi
Plugin
Layout
Details
Layout Complexity Graph
Size Author Comment
Circular O(N) 1
to
1M
nodes Ma6
Groeninger Used
to
show
distribuBon,
ordered
layout
Radial
Axis O(N) 1
to
1M
nodes Ma6
Groeninger Show
ordered
groups
(homophily)
Force
Atlas O(N²) 1
to
10K
nodes Mathieu
Jacomy Slow,
but
uses
edge
weight
and
few
biases
Force
Atlas
2 O(N*log(N)) 1
to
1M
nodes Mathieu
Jacomy
(does
use
weight)
OpenOrd O(N*log(N)) 100
to
1M
nodes S.
MarBn,
W.
M.
Brown,
R.
Klavans,
and
K.
Boyack
Focus
on
clustering
(uses
edge
weight)
Yifan
Hu
O(N*log(N)) 100
to
100K
nodes Yifan
Hu (no
edge
weight)
Fruchterman-‐Rheingold O(N²) 1
to
1K
nodes Fruchterman
&
Rheingold!
ParBcle
system,
slow
(no
edge
weight)
GeoLayout O(N) 1
to
1M
nodes Alexis
Jacomy Uses
Lat/Long
for
layout
h6ps://gephi.org/2011/new-‐tutorial-‐layouts-‐in-‐gephi/
52. 52
Weight
2:
Force
Atlas Weight
4:
Force
Atlas Weight
4:
Yifan
Hu
Unweighted
dolphins,
Force
Atlas
Effect of An Artificial Weight on the Layout
53. Simple
Orderings
of
Nodes
in
Circular
Layout
53
Dolphins
colored
by
modularity
class
(community)
in
Gephi
“Dual
Circle”
layout
with
most
popular
dolphin
in
center
Circular
Layout
ordered
by
Degree
Sorted
by
Modularity
54. Gephi
Workflowsà
Sigma.js
/
D3…
Gephi.org:
Open
source,
runs
on
Mac,
Linux,
PC
Output
high
quality
images
that
are
staBc
(from
Preview)
or…
Sigma.js
:
Will
display
a
gexf
gephi
layout
file
with
minimal
work,
using
a
plugin
interpreter
for
sigma
site
export
Also
offers
a
force-‐directed
layout
plugin
for
graphs
without
x&y
coords
Does
CANVAS
drawing,
not
SVG
D3:
Export
JSON
from
Gephi
and
load
into
D3
network
layout
—
can
calculate/layout
your
x/y
coords
(and
other
stats)
in
Gephi
and
then
use
them
in
a
staBc
layout
in
D3!
Also
see
cola.js.
61. Ger
Hobbelt
in
D3:
h6p://bl.ocks.org/3637711
Hybrid
Method:
Use
algorithmic
layout,
and
then
adjust
nodes
by
hand.
(Can
be
done
in
Gephi
or
D3.)
Also read http://bost.ocks.org/mike/example/#2
65. A
Nice
D3
tutorial
with
some
good
UI
65
Jim
Vallandingham
h6p://flowingdata.com/2012/08/02/how-‐to-‐make-‐an-‐interacBve-‐network-‐visualizaBon/
Also
see
his
OpenVis
talk:
h6p://vallandingham.me/abusing_the_force.html
66. Demo
Based
on
That
Tutorial
66
Not online, http://localhost:8002/
68. Design
Reminders
(1/2)
Do
data
analysis
/
reducBon
-‐
why
would
you
want
to
show
1T
of
network
data?
Calculate
and
reveal
important
facts
about
node
relaBonships.
Make
it
interacBve
-‐
details
on
demand.
Help
people
find
things
in
your
network!
(Search?)
Show
more
on
hover/click
To
o
m
uch
d
ata
=Not
alw
ays
go
o
d
d
ata
science!
69. Design
Reminders
(2/2)
Different
layouts
communicate
different
things
to
your
viewer
-‐
choose
wisely.
Take
care:
people
will
infer
things
from
proximity/similarity
even
if
it
was
not
intended!
Consider
if
it
has
to
be
a
node-‐edge
display
at
all:
Is
it
the
stats
you
care
about?
The
important
nodes
who
branch
sub-‐communiBes?
The
ones
with
the
most
in/out
links?
The
“top
influencers”?
69
73. A
Few
More
References
Jeff
Heer
class
slides:
h6p://hci.stanford.edu/
courses/cs448b/w09/lectures/20090204-‐
GraphsAndTrees.pdf
A
great
in-‐progress
book
on
networks:
h6p://
barabasilab.neu.edu/networksciencebook/
Mark
Newman’s
new
book-‐
NetWorks:
An
IntroducBon
Tutorial
on
Gephi:
h6ps://t.co/ZsMekjkfMt
Journal
of
Graph
Algorithms
and
ApplicaBons:
h6p://jgaa.info/home.html
Jim
Vallandingham’s
D3
network
tutorials:
h6p://flowingdata.com/2012/08/02/how-‐to-‐
make-‐an-‐interacBve-‐network-‐visualizaBon/,
h6p://vallandingham.me/
bubble_charts_in_d3.html
Brian
Keegan’s
post
about
GamerGate
tweets
and
the
dangers
of
network
vis
ww.brianckeegan.com/2014/10/my-‐15-‐
Robert
Kosara’s
post:
h6p://
eagereyes.org/techniques/graphs-‐hairball
Lane
Harrison’s
post:
h6p://blog.visual.ly/
network-‐visualizaBons/
MS
Lima’s
book
Visual
Complexity
and
site
A
couple
arBcles
on
community
structure:
Overlapping
Community
DetecBon
in
Networks:
State
of
the
Art
and
ComparaBve
Study
by
Jierui
Xie,
Stephen
Kelley,
Boleslaw
K.
Szymanski
Empirical
Comparison
of
Algorithms
for
Network
Community
DetecBon
by
Leskovec,
Lang,
Mahoney
My
posts
on
NetworkX
with
D3
and
Twi6er
network
vis
with
Gephi