Slides related to the papers:
- Fionda V., Gutierrez C., Pirrò G. "Knowledge Maps of Web Graphs". n the proceedings of the “14th International Conference on Principles of Knowledge Representation and Reasoning (KR2014)”.
- Fionda V., Pirrò G., Gutierrez C. "The Map Generator Tool". Demo session at the “13th International Semantic Web Conference (ISWC2014)”.
1. Formal Maps and their Algebra
Valeria Fionda, Claudio Gutierrez Giuseppe Pirr´o
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 1 / 43
6. Outline
1 Introduction
2 Contribution
3 The notion of map
4 Related research
5 Preliminaries
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 2 / 43
7. Outline
1 Introduction
2 Contribution
3 The notion of map
4 Related research
5 Preliminaries
6 Definition of Map
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 2 / 43
8. Outline
1 Introduction
2 Contribution
3 The notion of map
4 Related research
5 Preliminaries
6 Definition of Map
7 Maps as mathematical objects
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 2 / 43
9. Outline
1 Introduction
2 Contribution
3 The notion of map
4 Related research
5 Preliminaries
6 Definition of Map
7 Maps as mathematical objects
8 Regions and maps on the Web
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 2 / 43
10. Introduction
Outline
1 Introduction
2 Contribution
3 The notion of map
4 Related research
5 Preliminaries
6 Definition of Map
7 Maps as mathematical objects
8 Regions and maps on the Web
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 3 / 43
11. Introduction
What is a map?
Maps are artifacts that orient users in information spaces
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 4 / 43
12. Introduction
What is a map?
Maps are artifacts that orient users in information spaces
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 4 / 43
13. Introduction
What is a map?
Maps are artifacts that orient users in information spaces
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 4 / 43
14. Introduction
Goals
Our broad goal is to investigate how cartographical principles can be
applied over the Web space
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 5 / 43
15. Introduction
Goals
Our broad goal is to investigate how cartographical principles can be
applied over the Web space
The web is a graph
In particular we are interested in the Web of linked data, that is a
huge, distributed, directed, labeled multigraph
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 5 / 43
16. Introduction
Goals
Our broad goal is to investigate how cartographical principles can be
applied over the Web space
The web is a graph
In particular we are interested in the Web of linked data, that is a
huge, distributed, directed, labeled multigraph
Specific goals:
1) We want to build maps of a graph
2) Algebra of maps
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 5 / 43
17. Contribution
Outline
1 Introduction
2 Contribution
3 The notion of map
4 Related research
5 Preliminaries
6 Definition of Map
7 Maps as mathematical objects
8 Regions and maps on the Web
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 6 / 43
18. Contribution
Contribution
Our contributions are:
1 We provide a formal general framework to cope with the notion of
map as a means to abstract graphs.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 7 / 43
19. Contribution
Contribution
Our contributions are:
1 We provide a formal general framework to cope with the notion of
map as a means to abstract graphs.
2 We studied the properties of different types of maps and developed
efficient algorithms to compute them.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 7 / 43
20. Contribution
Contribution
Our contributions are:
1 We provide a formal general framework to cope with the notion of
map as a means to abstract graphs.
2 We studied the properties of different types of maps and developed
efficient algorithms to compute them.
3 We introduced an algebra for maps.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 7 / 43
21. Contribution
Contribution
Our contributions are:
1 We provide a formal general framework to cope with the notion of
map as a means to abstract graphs.
2 We studied the properties of different types of maps and developed
efficient algorithms to compute them.
3 We introduced an algebra for maps.
4 We tackle the problem of how to apply our framework to the Web:
1 By investigating how to specify regions of the Web - new semantics of
Web navigational languages returning graphs
2 Obtaining maps from those regions
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 7 / 43
22. Contribution
Contribution
Our contributions are:
1 We provide a formal general framework to cope with the notion of
map as a means to abstract graphs.
2 We studied the properties of different types of maps and developed
efficient algorithms to compute them.
3 We introduced an algebra for maps.
4 We tackle the problem of how to apply our framework to the Web:
1 By investigating how to specify regions of the Web - new semantics of
Web navigational languages returning graphs
2 Obtaining maps from those regions
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 7 / 43
23. Contribution
Contribution
Our contributions are:
1 We provide a formal general framework to cope with the notion of
map as a means to abstract graphs.
2 We studied the properties of different types of maps and developed
efficient algorithms to compute them.
3 We introduced an algebra for maps.
4 We tackle the problem of how to apply our framework to the Web:
1 By investigating how to specify regions of the Web - new semantics of
Web navigational languages returning graphs
2 Obtaining maps from those regions
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 7 / 43
24. Contribution
Contribution
Our contributions are:
1 We provide a formal general framework to cope with the notion of
map as a means to abstract graphs.
2 We studied the properties of different types of maps and developed
efficient algorithms to compute them.
3 We introduced an algebra for maps.
4 We tackle the problem of how to apply our framework to the Web:
1 By investigating how to specify regions of the Web - new semantics of
Web navigational languages returning graphs
2 Obtaining maps from those regions
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 7 / 43
25. The notion of map
Outline
1 Introduction
2 Contribution
3 The notion of map
4 Related research
5 Preliminaries
6 Definition of Map
7 Maps as mathematical objects
8 Regions and maps on the Web
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 8 / 43
26. The notion of map
A region
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Influeces
between
directors
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 9 / 43
27. The notion of map
Distinguished nodes
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Influeces
between
directors
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 10 / 43
28. The notion of map
Examples of maps
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Influeces
between
directors
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
Martin
Scorsese
John
Ford
Quentin
Tarantino
Stanley
Kubrick Woody
Allen
John
Ford
Quentin
Tarantino
Stanley
Kubrick Woody
Allen
Map 2Map 1
e1
e2
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 11 / 43
29. The notion of map
Abstraction level
A map should:
Represent the region
Be concise
Keep the connectivity
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 12 / 43
30. The notion of map
Abstraction level
A map should:
Represent the region
Be concise
Keep the connectivity
How much of the original region has to be included in the map?
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 12 / 43
31. Related research
Outline
1 Introduction
2 Contribution
3 The notion of map
4 Related research
5 Preliminaries
6 Definition of Map
7 Maps as mathematical objects
8 Regions and maps on the Web
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 13 / 43
32. Related research
Graph summarization
Graph summarization [1,2,3]:
Goal: produce a compressed representation of an input graph G
Determine a function F in order to find a simplified structure Gs
satisfying some requirements
Removes some of the details from the graphs in order to reduce space
consumption by usually clustering nodes in partitions.
[1] C. Faloutsos, K.S. McCurley, and A. Tomkins. Fast Discovery of Connection Subgraphs. In
KDD, pages 118-127. ACM, 2004.
[2] J. Adibi, H. Chalupsky, E. Melz, A. Valente, et al. The KOJAK Group Finder: Connecting
the Dots via Integrated Knowledge-based and Statistical Reasoning. In AAAI, pages 800-807,
2004.
[3] F. Zhou, S. Malher, and H. Toivonen. Network Simplification with Minimal Loss of
Connectivity. In ICDM, pages 659-668. IEEE, 2010.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 14 / 43
33. Related research
Graph indexing
Graph indexing [4]:
Goal: produce a list of graph substructures with references to the
place where they can be found
Make querying the graph faster
[4] X. Yan and J. Han. Graph Indexing. Managing and Mining Graph Data 2010, pages 161-180
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 15 / 43
34. Related research
Differences
1 These techniques work on the whole graphs, they do not provide
means to specify regions.
Benefit: the web cannot be mapped altogheter! Isolated portions
should be considered (according to user interests)
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 16 / 43
35. Related research
Differences
1 These techniques work on the whole graphs, they do not provide
means to specify regions.
Benefit: the web cannot be mapped altogheter! Isolated portions
should be considered (according to user interests)
2 We focus also on giving machine readable representations
structures and are represented in a standard format to be extended,
reused and combined.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 16 / 43
36. Related research
Differences
1 These techniques work on the whole graphs, they do not provide
means to specify regions.
Benefit: the web cannot be mapped altogheter! Isolated portions
should be considered (according to user interests)
2 We focus also on giving machine readable representations
structures and are represented in a standard format to be extended,
reused and combined.
3 Our map frameworks allow to obtain maps that can be treated as
mathematical objects by defining an algebra over maps.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 16 / 43
37. Preliminaries
Outline
1 Introduction
2 Contribution
3 The notion of map
4 Related research
5 Preliminaries
6 Definition of Map
7 Maps as mathematical objects
8 Regions and maps on the Web
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 17 / 43
38. Preliminaries
Notation
Let G = (VG , EG ) be a directed graph, VG the set of nodes, EG the set of
edges and u, v nodes in G and N ⊆ VG be a set of nodes:
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Influeces
between
directors
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
N={Martin Scorsese, Woody Allen}
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 18 / 43
39. Preliminaries
Notation
Let G = (VG , EG ) be a directed graph, VG the set of nodes, EG the set of
edges and u, v nodes in G and N ⊆ VG be a set of nodes:
u → v denotes an edge (u, v) ∈ EG
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Influeces
between
directors
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
John Ford → Martin Scorsese
N={Martin Scorsese, Woody Allen}
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 18 / 43
40. Preliminaries
Notation
Let G = (VG , EG ) be a directed graph, VG the set of nodes, EG the set of
edges and u, v nodes in G and N ⊆ VG be a set of nodes:
u → v denotes an edge (u, v) ∈ EG
u v denotes a path from u to v in G
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Influeces
between
directors
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
John Ford → Martin Scorsese
John Ford Stanley Kubrick
N={Martin Scorsese, Woody Allen}
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 18 / 43
41. Preliminaries
Notation
Let G = (VG , EG ) be a directed graph, VG the set of nodes, EG the set of
edges and u, v nodes in G and N ⊆ VG be a set of nodes:
u → v denotes an edge (u, v) ∈ EG
u v denotes a path from u to v in G
u Nv denotes a path from u to v in G not passing through
intermediate nodes in N
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Influeces
between
directors
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
John Ford → Martin Scorsese
John Ford Stanley Kubrick
N={Martin Scorsese, Woody Allen}
John Ford N Stanley Kubrick
NOTJohn Ford N Paul T. Anderson
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 18 / 43
42. Definition of Map
Outline
1 Introduction
2 Contribution
3 The notion of map
4 Related research
5 Preliminaries
6 Definition of Map
7 Maps as mathematical objects
8 Regions and maps on the Web
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 19 / 43
43. Definition of Map
Map of a graph
Definition
A map M = (VM, EM) of G is a graph such that VM ⊆ VG and each edge
(x, y) ∈ EM implies x y in G
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 20 / 43
44. Definition of Map
Map of a graph
Definition
A map M = (VM, EM) of G is a graph such that VM ⊆ VG and each edge
(x, y) ∈ EM implies x y in G
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 20 / 43
45. Definition of Map
Complete map of a graph
Definition
A map M = (VM, EM) of G is complete iff x y in G implies x y in
M.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 21 / 43
46. Definition of Map
Complete map of a graph
Definition
A map M = (VM, EM) of G is complete iff x y in G implies x y in
M.
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 21 / 43
47. Definition of Map
Complete map of a graph
Definition
A map M = (VM, EM) of G is complete iff x y in G implies x y in
M.
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 22 / 43
48. Definition of Map
Complete map of a graph
Completeness is not always enough to summarize information via maps
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 23 / 43
49. Definition of Map
Complete map of a graph
Completeness is not always enough to summarize information via maps
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 24 / 43
50. Definition of Map
Complete map of a graph
Completeness is not always enough to summarize information via maps
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 25 / 43
51. Definition of Map
Complete map of a graph
Completeness is not always enough to summarize information via maps
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
Redundant: paths from John
Ford to Quentin Tarantino in G
only pass for some distinguished
nodes
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 26 / 43
52. Definition of Map
Route-Complete map of a graph
Definition
A map M = (VM, EM) of G is route-complete iff x VM
y in G implies
x → y in M
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 27 / 43
53. Definition of Map
Route-Complete map of a graph
Definition
A map M = (VM, EM) of G is route-complete iff x VM
y in G implies
x → y in M
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 27 / 43
54. Definition of Map
Non-Redundant map of a graph
Definition
A map M = (VM, EM) of G is non-redundant iff x → y in M implies
x VM
y in G.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 28 / 43
55. Definition of Map
Non-Redundant map of a graph
Definition
A map M = (VM, EM) of G is non-redundant iff x → y in M implies
x VM
y in G.
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
Martin
ScorseseJohn
Ford
Quentin
Tarantino
Stanley
Kubrick
Woody
Allen
David
Lynch
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 28 / 43
56. Definition of Map
Good map of a graph
Definition
A map M = (VM, EM) of G is good iff it is:
complete (x y in G implies x y in M)
route-complete (x VM
y in G implies x → y in M)
non-redundant (x → y in M implies x VM
y in G)
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 29 / 43
57. Definition of Map
Good map of a graph
Lemma
A map M = (VM, EM) of G is good iff x → y in M ⇔ x VM
y in G,
∀x, y ∈ VM
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 30 / 43
58. Definition of Map
Good map of a graph
Lemma
A map M = (VM, EM) of G is good iff x → y in M ⇔ x VM
y in G,
∀x, y ∈ VM
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 30 / 43
59. Definition of Map
Good map of a graph
Lemma
A map M = (VM, EM) of G is good iff x → y in M ⇔ x VM
y in G,
∀x, y ∈ VM
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 31 / 43
60. Definition of Map
Good map of a graph
Lemma
A map M = (VM, EM) of G is good iff x → y in M ⇔ x VM
y in G,
∀x, y ∈ VM
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 32 / 43
61. Definition of Map
Good map of a graph
Theorem
Let G = (VG , EG ) be a graph. Given N ⊆ V , there is a unique good map
M over G.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 33 / 43
62. Definition of Map
Good map of a graph
Theorem
Let G = (VG , EG ) be a graph. Given N ⊆ V , there is a unique good map
M over G.
(Sketch).
Existence and uniqueness follow from the previous lemma. The edge
x → y in M is defined by the existence of a particular path in G.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 33 / 43
63. Definition of Map
Computing good maps of a graph
Martin
Scorsese
John
Ford
Orson
Welles
Quentin
Tarantino
Stanley
Kubrick
Tim
Burton
Woody
Allen
Lars von
Trier
David
Lynch
Peter
Jackson
Terry
Gilliam
David
Fincher
Greg
Harrison
Paul T.
Anderson
Nicolas
Renf
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 34 / 43
64. Definition of Map
Computing good maps of a graph
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 35 / 43
65. Definition of Map
Computing good maps of a graph
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 36 / 43
66. Maps as mathematical objects
Outline
1 Introduction
2 Contribution
3 The notion of map
4 Related research
5 Preliminaries
6 Definition of Map
7 Maps as mathematical objects
8 Regions and maps on the Web
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 37 / 43
67. Maps as mathematical objects
Algebra of maps
Theorem
Let G = (VG , EG ) be a graph and M(G) the set of all good maps over G.
Mi = (VMi
, EMi
) ∈ M(G) is a map. Then:
1 The binary relation over M(G), defined by M1 M2 iff
VM1 ⊆ VM2 , is a partial order on M(G).
2 The order induces a Boolean algebra (M(G), , , G, ∅), where:
M1 M2 is the unique good map of G over VM1 ∪ VM2 ; M1 M2 is
the unique good map of G over VM1 ∩ VM2 .
3 There is an isomorphism of Boolean algebras from the algebra of sets
(P(V ), ∪, ∩, V , ∅) to (M(G), , , G, ∅), given by N MN (the
unique good map of N over G).
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 38 / 43
68. Regions and maps on the Web
Outline
1 Introduction
2 Contribution
3 The notion of map
4 Related research
5 Preliminaries
6 Definition of Map
7 Maps as mathematical objects
8 Regions and maps on the Web
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 39 / 43
69. Regions and maps on the Web
Navigational language to specify regions
Navigational languages [5,6,7] declaratively specify nodes in a graph
or sub-graph (possibly the Web).
No information about node connection is provided and then they are
not suitable for building maps.
We defined a general navigational language to deal with subgraphs
besides sets of nodes.
[5] W. W. W. Consortium. XML Path Language (Xpath) Recommendation., Nov. 1999.
[6] V. Fionda, C. Gutierrez, and G. Pirr´o. Semantic Navigation on the Web of Data:
Specification of Routes, Web Fragments and Actions. In WWW, pages 281290. ACM, 2012.
[7] F. Alkhateeb, J.-F. Baget, and J. Euzenat. Extending SPARQL with Regular Expression
Patterns (for querying RDF). JWS, 7(2):5773, 2009.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 40 / 43
70. Regions and maps on the Web
Our framework
The high level specification for building maps of the Web is:
1 Specify the resources of interest (distinguished nodes): We leverage a
navigational language.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 41 / 43
71. Regions and maps on the Web
Our framework
The high level specification for building maps of the Web is:
1 Specify the resources of interest (distinguished nodes): We leverage a
navigational language.
2 Build the region R corresponding to this specification: We enhanced
the semantics of our navigational language to return subgraphs
besides sets of pairs of nodes.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 41 / 43
72. Regions and maps on the Web
Our framework
The high level specification for building maps of the Web is:
1 Specify the resources of interest (distinguished nodes): We leverage a
navigational language.
2 Build the region R corresponding to this specification: We enhanced
the semantics of our navigational language to return subgraphs
besides sets of pairs of nodes.
3 Build a formal map corresponding to the region R: We build maps
from regions by using the map framework discussed in the talk.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 41 / 43
73. Regions and maps on the Web
The implemented system
The map framework has been implemented in a tool, which can be
downloaded at the address http://mapsforweb.wordpress.com.
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 42 / 43
74. THANK YOU
V. Fionda, C. Gutierrez, G. Pirr´o Formal Maps and their Algebra 43 / 43