Qualities and Attributes
In MAS field, researchers synthesized the properties most often associated to software agents. It is mainly about perception, immersion into an environment, autonomy, flexibility, reactivity, adaptability, the ability to cooperate, coordination and negotiation, communication, mobility, replication and continuous execution.
When we tried to integrate within the same agent two properties such as mobility and autonomy, our work quickly led us to the conclusion that these two properties cannot be treated in the same way and to distinguish two categories of properties which have a deeply different nature: qualities and attributes.
Qualities are properties of an agent with elastic and not well determined borders, with not easily measurable (even non measurable)
aspects. A quality is complex by nature, i.e. it is difficult (perhaps impossible) to have an intimate knowledge of it. Qualities are
properties with their contents changing according to the points of view which one can have. They authorize multiple models and different
interpretations, when these interpretations are not contradictory.
Two properties which can be identified as qualities are autonomy and intelligence.
Mobility, replication and perception are properties intrinsically less difficult to understand than qualities.
They are generally reduced to a mechanism and one or some well defined functioning procedures. We called these properties attributes.
An attribute is an immediately comprehensible property by a modelisator: if mobility, is taken as example, this modelisator
knows if this specific agent or entity is mobile or is not.
By definition, an attribute can be simple or complicated but never complex.
In short, from the properties point of view, a software agent is considered as a set of qualities and/or attributes.
The quality/attribute taxonomy was used to determine and to analyze the points of complexity which are internal to software agents. It also provides a new agent typology - agent with qualit(y|ies), agent with attribute(s), hybrid agent - complementary to the existent classifications (ex: cognitive/reactive agent).