This document presents research on developing a novel visualization called Spherule diagrams for social networks. Spherule diagrams address limitations of traditional visualizations like graphs, Euler diagrams, and treemaps by improving complexity, scalability, and layout issues. An empirical study evaluated Spherule diagrams against Euler diagrams on 28 participants and found Spherule diagrams had fewer errors and faster task completion times, and were preferred by 75% of participants. Future work aims to further optimize Spherule diagram graphs and conduct larger-scale user evaluations.

1. SPHERULE DIAGRAMS WITH GRAPH FOR
SOCIAL NETWORK VISUALIZATION
Mithileysh Sathiyanarayanan and Donato Pirozzi
University of Brighton, UK and University of Salerno, Italy
COMSNETS 2016
Bangalore, India
Contact: M.Sathiyanarayanan@brighton.ac.uk

2. AIM OF THE RESEARCH
The main aim of this research is to develop a
novel visualization for social networks which
can significantly improve the analysis of social
relationships by improving complexity,
scalability and layout issues.

3. MOTIVATION
Social network analysis (SNA) has become a
greater force in the field of information
visualization which focuses on the social
relationships and interactions among social
actors rather than study individuals
themselves who use social networks such as
Facebook, Twitter, Google+ etc.
So, it is a strategy to investigate large social
structures and trying often to pattern them
effectively for better understanding and easy
navigation.

4. OTHER MOTIVATIONS
There is a big need of visualizing tools for
data analysts in various companies to
understand online social relationships for
advertising and promoting certain products.
However, the complexity and scale of digital
communication motivates researchers to find
alternative ways to represent social networks
in visual form which are more efficient in
communicating information.

5. PURPOSE OF SOCIAL NETWORK VISUALIZATION
Identifying the actors of a network
Understanding relationships in a network
Aggregating the information on a social
network

6. GRAPHS
Drawbacks:
Edge-clutter issues
Complexity issues
Scalability issues
Layout issues

7. EULER DIAGRAMS
Drawbacks:
Curve-clutter issues
Complexity issues
Scalability issues
Layout issues

8. TREEMAP DIAGRAMS
Drawbacks:
Tree-clutter issues
Complexity issues
Scalability issues
Layout issues

9. EULER DIAGRAMS WITH GRAPH
Drawbacks:
Curve-clutter issues
Edge-clutter issues
Complexity issues
Scalability issues
Layout issues

10. TREEMAP DIAGRAMS WITH GRAPH
Drawbacks:
Tree-clutter issues
Edge-clutter issues
Complexity issues
Scalability issues
Layout issues

11. WHAT IS THE CHALLENGE?
In this research, visualization of a social network using
a traditional Euler diagram is challenged by our novel
visualization, Spherule diagram.
So,
Euler diagram with graph and Spherule diagram with
graph visualizations were designed for a Twitter
network and then compared by twenty-eight
participants in an empirical form (evaluation).

12. OUR CONTRIBUTIONS
Developed a novel visual method to improve
social relationship analysis;
Designed, evaluated and compared Spherule
diagrams with Euler diagrams.
Fig:
Spherule diagram
with graph

13. DESIGN OF THE STUDY
 Diagrams were drawn using the software
Inkscape. We considered three different sizes of
curves: small, medium and large.
 28 participants were randomly selected from the
various companies for the study.
 Nineteen of the participants were male, nine
female, and their age varied from 26 to 43 years
with 29.5 years as the mean value for their age.
 Next, all participants were asked questions
based on the visualizations.
 Diagrams drawn were randomised for the
participants.

14. SOFTWARE FOR THE STUDY
 The empirical study was conducted using a
software developed by our team called as
‘Research Vehicle’.
 The diagrams along with the questions were
pinned in the software.
 The software collected the errors committed by
the participants and the time-taken to answer each
question.

15. GOAL OF THE DESIGNED EVALUATION STUDY
1) To evaluate and compare the users’ task performance
of the proposed Spherule diagrams with graph
(SDG) with the task performance of Euler diagrams
with graph (EDG).
2) To evaluate the impact of the number of sets,
presence of regions, data items, social relationships
in SDG and EDG visualization on their performance.
3) To evaluate the users’ preference on the two social
network visualizations.

16. TASK PERFORMANCE STUDY
The task performance study related questions are:
1) If X follows Y and how many people Y follows?
2) Who are the common people X1 follows with X2?
3) How many people X1 follows which does not
include common with X2?

17. EXAMPLE - QUESTIONS
1. If LUKE follows Tom
Cruise and how many
people Tom Cruise
follows?
2. Who are the common
people ADAM follows
with STEVE?
3. How many people
LUKE follows which
does not include common
with JOHN?

18. EXAMPLE - ANSWERS
1. If LUKE follows Tom
Cruise and how many
people Tom Cruise follows?
Ans = 2
2. Who are the common
people ADAM follows with
STEVE? Ans = None
3. How many people LUKE
follows which does not
include common with
JOHN? Ans = 5

19. SPHERULE DIAGRAM
Euler diagram re-drawn as Spherule diagram

20. DIAGRAM LEVELS FOR THE STUDY

21. Level 1 (4 sets): (a) Euler diagram (b) Spherule diagram
DIAGRAMS FOR THE STUDY

22. Level 2 (6 sets): (a) Euler diagram (b) Spherule diagram
DIAGRAMS

23. Level 3 (8 sets): (a) Euler diagram (b) Spherule diagram
DIAGRAMS

24. RESULT TABLE
1. Errors are less in Spherule diagrams when compared with Euler diagrams.
2. Time-taken to answer questions are also less in Spherule diagrams when
compared with Euler diagrams.

25. RESULTS-1
Accuracy Performance:
Though there are less errors committed by the
participants in answering Spherule diagram
questions but all the three levels revealed no
significant difference between Euler diagrams and
Spherule diagrams based on the chi-square test.
Time Performance:
 Participants took less time in answering Spherule
diagram questions and all the three levels revealed
significant difference between Euler diagrams and
Spherule diagrams based on the ANNOVA test.

26. PREFERENCE STUDY
The preference study related questions are:
1) How many people are in the network?
2) How many social connections exist in the
network?
3) Which person has the most tweets?
4) How many connections Adam has?
5) Are Mark and Adam connected?
6) What are the common interests between John and
Luke?

27. RESULTS-2
Preference Results:
From the 28 participants, 21 participants (75%)
preferred Spherule diagrams based on its simplicity,
comprehensiveness, navigation, alignment (layout),
set ordering and data items ordering characteristics.
One of the main feedback from the participants
were to reduce further clutter in the graph edges of
Spherule diagrams with graph.

28. BASED ON THE RESULTS
Aesthetics: Compared to Euler diagrams’ curve
crossing, Spherule diagrams does not have any
spheres crossing and there is no loss of
information.
The other positives about the Spherule diagrams
are simple in construction (not complex), easy to
navigate, no clutter, set labels are in alphabetical
order and regions are numbered sequentially.

29. FUTURE WORKS
We would like to improve Spherule diagrams by
optimizing graphs.
More User Evaluation Studies are needed to further
evaluate the visualization efficiency and
effectiveness.
For practical work on Spherule diagrams, we are
thinking of providing a web-based implementation.
In the next study, we will use crowdsourcing for
evaluation of the visualizations since the results
obtained with 28 participants of this study must be
verified for larger groups of participants.

30. Thank You
and
Any Questions?