Process Model
The current process model for data mining provides
an overview of the life cycle of a data mining project. It contains
the corresponding phases of a project, their respective tasks, and
relationships between these tasks. At this description level, it
is not possible to identify all relationships. There possibly exists
relationships between all data mining tasks depending on goals,
background and interest of the user, and most importantly depending
on the data. An electronic copy of the CRISP-DM Version 1.0 Process
Guide and User Manual is available free of charge. This contains
step-by-step directions, tasks and objectives for each phase of
the Data Mining Process. Download CRISP
1.0 Process and User Guide.

Figure: Phases of the CRISP-DM
Process Model
The life cycle of a data mining project consists
of six phases. The sequence of the phases is not strict. Moving
back and forth between different phases is always required. It depends
on the outcome of each phase which phase, or which particular task
of a phase, that has to be performed next. The arrows indicate the
most important and frequent dependencies between phases.
The outer circle in the figure symbolizes the
cyclic nature of data mining itself. A data mining process continues
after a solution has been deployed. The lessons learned during the
process can trigger new, often more focused business questions.
Subsequent data mining processes will benefit from the experiences
of previous ones.
Below follows a brief outline of the phases:
Business Understanding
This initial phase focuses on understanding
the project objectives and requirements from a business perspective,
and then converting this knowledge into a data mining problem definition,
and a preliminary plan designed to achieve the objectives.
Data Understanding
The data understanding phase starts with
an initial data collection and proceeds with activities in order
to get familiar with the data, to identify data quality problems,
to discover first insights into the data, or to detect interesting
subsets to form hypotheses for hidden information.
Data Preparation
The data preparation phase covers all activities
to construct the final dataset (data that will be fed into the modeling
tool(s)) from the initial raw data. Data preparation tasks are likely
to be performed multiple times, and not in any prescribed order.
Tasks include table, record, and attribute selection as well as
transformation and cleaning of data for modeling tools.
Modeling
In this phase, various modeling techniques
are selected and applied, and their parameters are calibrated to
optimal values. Typically, there are several techniques for the
same data mining problem type. Some techniques have specific requirements
on the form of data. Therefore, stepping back to the data preparation
phase is often needed.
Evaluation
At this stage in the project you have built
a model (or models) that appears to have high quality, from a data
analysis perspective. Before proceeding to final deployment of the
model, it is important to more thoroughly evaluate the model, and
review the steps executed to construct the model, to be certain
it properly achieves the business objectives. A key objective is
to determine if there is some important business issue that has
not been sufficiently considered. At the end of this phase, a decision
on the use of the data mining results should be reached.
Deployment
Creation of the model is generally not the
end of the project. Even if the purpose of the model is to increase
knowledge of the data, the knowledge gained will need to be organized
and presented in a way that the customer can use it. Depending on
the requirements, the deployment phase can be as simple as generating
a report or as complex as implementing a repeatable data mining
process. In many cases it will be the customer, not the data analyst,
who will carry out the deployment steps. However, even if the analyst
will not carry out the deployment effort it is important for the
customer to understand up front what actions will need to be carried
out in order to actually make use of the created models.
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