1.2 Create and edit facts
1.3 Concept insertion
1.4 Relation insertion
1.6 Reduced edition
is labeled bipartite graph. One class of nodes (the concept nodes) is
used to represent entities of the discourse universe. A concept node
is labeled by a concept type (e.g. Painter,
or a conjunctive type such as Painter,Catalan) and,
possibly, by an
individual (e.g. Picasso).
A concept node which is labeled by a concept type without an
individual is called a generic concept node. Such a node represents
an unidentified element of the type. For instance, contrarily to a
node labeled [Painter : Picasso]
representing the painter
Picasso, a concept node labeled [Painter]
represents “a” painter.The
second class of nodes represents the relationships between the
entities (represented by the concept nodes). For instance, if
Guernica is an individual representing the well-known painting realized
Picasso then a relation node labeled (hasPainted)
could relate the concept node [Painter
: Picasso] to
the concept node
The edge between
: Picasso] is
labeled by 1, and the
edge between (hasPainted)
: Guernica] is
labeled by 2. This
edge labeling is used to represent different roles (e.g. to
distinguish the subject
from the complement). It is also possible to say that two different
concept nodes represent the same entity by linking them by a
below is described by a simple graph:
New facts and sets of facts can be created by the popup menus of "Facts" item and sub-items from project tree. After creating and naming a new graph, edit by selecting "Edit" menu, or by clicking twice on tree item. An empty graph editor is opened. Use same "Edit option" to re-open existing facts.
the fact graph contains too many vertices, it couldn't be possible
to display the entire graph. In this case the "Edit" menu
item opens the fact
graph "partially" (See 1.6 about partial edition). Choose "Edit whole
graph" to force the edition of all graph.
New concepts are inserted by using "Graph/insert vertex/Insert concept" from the main menu or the contextual popup menu or the local toolbar option . Concept types dragged from the concept types tree cause the creation of a new generic concept of these type. Concepts associated with individuals can be dragged from individual view. The newly created concepts have the privileged type of the individual.
Double left click
triggers a popup dialog to define type and
individual associated with selected concept. when the user begins to
text, a list of compatible terms are listed for both concept types and
individual is not already defined, it is automatically created in
knowledge base. For type definition, two modes are available: strict
mode doesn't accept undefined concept type, free mode accept references
to type which is not already defined in vocabulary. Check "free edition
mode" in preferences/General if needed. Modes also act on relation
Free edition can be useful during the building of the ontology, it avoids to go back to vocabulary editor. But, of course, it must be done, error messages can help:
Double left click triggers a popup dialog to define
type associated with selected relation. when user begin to
text, a list of relation types is listed.
The insertion of the relationship is not sufficient, we must also link the relation to adjacent concepts. Chapter 22.214.171.124 explains how to create an edge between two vertices.
Because the relation signature is ordered, edges between concepts and relation are associated with a number from 1 to relation arity. Edge order can be defined with popup menu on the selected edge.
You can also use double-click on selected edge, edge label successively takes all compatible values between the relation signature and the type of concept.
Of course, copy/paste mechanism can also be used to duplicate pieces of graphs inside the graph or from one to another. Pending edges cannot be copied. Otherwise this error message appears when you try to copy:
See chapter 126.96.36.199 about objects selection
In the fact graph paragraph of general section of preferences, the user can defined limits to choose partial edition rather than whole graph edition:
To edit parts of the graph without any error, we must query the graph (See chapter 5) and browse through projections in the result view.
Nested graphs can be inserted inside a concept, these subgraphs are typed (see chap.2.6 about nested types).
Why use nested graphs rather than a "flat" graph to represent informations ?
Consider, for instance, a cottage. It is possible to distinguish internal from external pieces of information about that cottage. The owner's name can be considered as an external piece of information concerning the cottage, whereas the number of rooms is internal information.
In information retrieval the ISBN number of a book can be considered as an external piece of information about that book, whereas the subject of the book is an internal piece of information. In these examples, the internal information can be also called (partial) description of the cottage or of the book).
Zooming is a related notion. Let us consider again the cottage example. Having the land registry position of the cottage, one may want to zoom into the cottage, e.g. one may want to have the cottage blue print, which can be considered as an internal information about the cottage. Or, at a deeper level, having the cottage blue print, one may want to know the furniture distribution in a specific room. In the book example, zooming can consist of obtaining the content of a chapter from a reference to this chapter (e.g. the number of this chapter).
Nested graphs can also be related to the notion of context. For instance, in the previous cottage example, the context of the furniture distribution (in a room) is precisely the room having this furniture distribution; the context of the content of a book chapter is precisely this chapter, and so on. The notion of context is close to the two previous notions of external versus internal piece of information, and to zooming. Indeed, zooming takes its full meaning when one knows from where the zooming is done, and an internal piece of information takes its full meaning when the piece of information whose it is an internal piece of information is known. In the forthcoming model only very simple contexts can be represented. Indeed, a context will be represented by a path of nested concept nodes. Thus, having in mind partial description as an intuitive meaning of what we aim to represent is more convenient than context. A partial description can be included into another partial description, thus a recursive model is proposed, and the entities are represented by a hierarchical structure. Similarly to the classical notion of ``boxes within boxes'' used in document processing, a nested graph consists of ``graphs within graphs''.
Example below say at first level that "Miss Michel has lost her cat, she shows a painting".
second level include a nested graph of the type "description" to describe the painting and finally, the coref link expresses the fact that the cat appearing on the painting is, indeed, the lost cat.
2.2 Nesting a graph
To insert a new nested graph inside a concept, select the concept and right click to obtain to contextual menu:
2.3 Nested graph edition
Nested graphs can be edited directly at the level of graph containing the parent concept (called the root graph), or edited alone as a classical graph.
Use contextual menu to edit the nested graph alone in the editor and return to the root graph:
Choose "Edit nested graph" option to edit the nested graph alone.
After editing the nested graph, choose this menu option to retreive to root graph edition
Sometimes it may be useful to view the graph root and the nested graphs at the same level. The + sign on the left of the nested graph expands the box to make the nested graph visible. It is useful to see the graphs but it becomes more complex to edit the content of the nested graph. However, it is very convenient to insert a pattern graph or drag selected objects to the nested graph.
below is described by a simple graph: