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In-Depth Information
The remainder of this paper is structured as follows: In Section 2 we give a
basic introduction into the REA ontology including an illustrative example. The
core of the paper in Section 3 presents our DSL for REA models. We elaborate on
the meta model of our REA DSL for describing duality models and value chains.
Furthermore, we use the same example as in Section 2 to illustrate our DSL.
Section 4 reports on our evaluation by means of a REA DSL tool. A summary
and remarks on future work conclude the paper in Section 5.
2 Resource - Event - Agent (REA)
2.1 The REA Ontology
The objective of the REA ontology is the conceptualization of common eco-
nomic phenomena of a firm independent of application-specific demands. REA
accounting information systems focus on economic exchanges as the central unit
of analysis. Instead of representing these exchanges with double-entry bookkeep-
ing artifacts (e.g. debits, credits, accounts), REA proposes concepts and patterns
to derive semantic models of economic exchanges and transformations. The un-
derlying assumption of REA is that all business enterprises operate in the same
manner [10] according to an entrepreneurial script: acquiring financial resources,
engaging in a chain of economic exchanges with other parties, each time giving
up an economic resource in return for another resource of greater value [10].
After executing this script, the business generates a justifiable profit after hav-
ing paid interests and creditors. This entrepreneurial script essentially discloses
the entrepreneurial rationale of a business. Hence, the REA ontology is not only
used to facilitate the design of accounting information systems but in particular
for business modeling.
The basic REA ontology is a stereotypical representation of an economic ex-
change as a core economic phenomenon [5]. This exchange is executed between
parties inside and outside of a firm's boundaries and follows a particular object
pattern (cf. [5], see also Figure 1(a) and 1(b)). In order to conceptualize this
pattern, the REA ontology suggests three concepts that constitute an exchange:
resource
,
event
,and
agent
. Resources are things being exchanged between partic-
ipating agents. In an exchange, an agent (inside agent) usually gives up control
of a resource to an outside agent in order to gain control over another resource.
Events occur in the course of executing economic activities. In REA basically two
types of events are distinguished:
increment
and
decrement
events. Extensions of
the REA ontology [11] also distinguish between
transfer
(exchanges with external
actors) and
transformation
(concerns value creation within the firm) events.
Furthermore, the following economic primitives (relationship types) are spec-
ified by the REA:
duality
,
stock-flow
,and
participation
. A duality relationship
connects decrement events with corresponding increment events and thus pro-
vides the rationale of individual economic activities. Stock-flow relationships con-
nect economic resources with economic events (decrement or increment events).
Depending on the connected event type, the following stock-flow relationship
