Process Mining Concepts
Concepts
Business object
A business object is an instance of structured information, or an entity, representing data about real world that is meaningful in a business context. Business objects are discovered and identified via various problem domain models as part of the information architecture of an organization, for example
- Customer
- Supplier
- Product
- Transaction
- Shipment
- Person
- Organization unit
It has a collection of attributes, which are relevant in a particular context. Business objects may have also various types of relationships with each other. Execution of software functions may change the attribute values as well as the relationships. Certain unique combinations of attribute values can be referred to as constituting the state of a business object. The business object can be associated with a state model describing the set of legitimate states and transitions between them. When a software function operates on a business object, it changes the state according to the programmed business logic and the constraints of the state model. Among different business object categories, transactions of various sorts are of particular interest in process mining.
Process
In an organizational context, a process is the way that people work together and apply methods and tools, to accomplish predefined common objectives. The objectives include the value that the output of the process is expected to produce to its stakeholders. A process model is an abstraction representing a process. It is the organization of work in terms of a functionally cohesive or causally connected set of activities triggered by a common event, executed by work roles, and creating or altering the state of some business object(s). A process case is a particular execution instance or an execution trace of a process. In process modeling context, a simple case contains a linear sequence of activities. A more complex case may contain parallel execution paths. In process mining context, the case contains only the end events of activities, not the activities themselves. Relevant attributes of a process case depend on the context. They apply to a case and the contained events as a whole. For example, in insurance claims processing, relevant case attributes could include:
- Customer
- Insurance policy
- Vehicle registration id
- Location of accident
- Claims handler
Every case attribute has a type, which defines what kind of data can be represented by the attribute, for example:
- Integer
- Logical truth (TRUE or FALSE)
- Date and time
Among different process categories, transactional processes are of particular interest, for example:
- Purchase-to-pay
- Quote-to-cash
- Request-to-resolution
- Idea-to-product
Activity
An activity is the basic building block of a process model. All human work is modeled as being performed within activities. An activity is executed by a work role. The purpose of an activity is to produce value adding output. Input from preceding activities and output to succeeding activities are provided in the form of business objects in well-defined states. In a digitalized business process, execution of an activity results in changing the state of business objects. An activity has a duration, and there may be waiting time or slack between the end of an activity and the start of the next activity.
File:FlowDurationBusinessProcessModel.png Figure X: Flow and duration in typical business process models
In computerized or digital transaction systems, event logs typically contain the end events only and the start events of activities are not necessarily recorded. Durations are calculated from the time between the end events. Flows are used to represent both the causality and the duration.
File:FlowDurationProcessMining.png Figure X: Flow and duration in event log based process mining
Event
An event is a change in the state of matters that has happened or is expected to happen, having a meaning in a particular context. The word event is also used to mean a software object inside a computer program that represents such an occurrence in a computing system, typically causing a state transition. An event does not have a duration. Durations are expressed in terms of the time between two events. An event typically signifies the beginning or completion of an activity or the state change of a business object. Process mining typically deals with these events. Relevant attributes of an event can be derived from the context and corresponding activity. Mandatory attributes for an event include a timestamp and an identifier associating it with a process case. Several optional attributes can be identified, depending on the context, for example:
- Person and work role that triggered the event
- Location where it was done
- Cost incurred by the event
- Work effort expended
- Environmental conditions
- Any activity specific factor that might affect the outcome
A process case may contain different types of events. Each event type has a special meaning related to the particular activity and business object state transition it is associated with.
Flow
In process mining context, a flow represents an identified causal relationship between state changes in a process model or business object. Typically, it signifies the transition from one state to the next state of a transaction. The duration of a flow is defined as the time between the events it connects. Note that in process mining, the analyst may choose the events included in the analysis using selection and filtering features of the tool, and the flows will be identified based on the included events only. In terms of a sate model, this equals to skipping uninteresting intermediate states in favor of a simpler or more focused analysis model. Flow occurrence is a historical fact or actual instance of a flow. A timestamp and identifiers of the related events are needed for distinct identification. Note that the flow occurrence is an artificial concept. It is the events that actually occur, and the flow is just a relationship between the events.
Variation
Process variations (or variants) divide a set of process cases into non-overlapping partitions based on their unique configuration of events, flows, and execution path they have taken. All cases in a variation have the same sequence of events and flows. The durations between the events may be different, though.
Transaction
A transaction is a protocol between participating entities intended to transfer value between the participants. Purchasing a product from a retail shop is an example of a simple transaction, where product of value is transferred from the seller to the buyer and money of equal value is transferred from the buyer to the seller. Transactions can be far more complex than buying a soda can. However, all parties of a transaction should have the same understanding about the protocol and current state of the transaction. It is important to know, whether or not an irrevocable commitment has been achieved by the parties. Transaction state models are a convenient way of explicating the protocol and communicating the current state. When a transaction is proceeds through its state model, it leaves an execution trace. The trace consists of events signifying the transitions of the transaction from one state to another. It is these events that are typically used in process mining work, processed by the various analysis algorithms. Transaction processing systems (like ERP) are usually state oriented, meaning that they do not reflect the way processes are modeled. They do not record the time it takes to perform an activity, but only the significant events i.e. state transitions of the transaction objects. However, the state transitions are usually the result of someone performing an activity, which then causes an event in the transaction processing system.
