Database Reference
In-Depth Information
GLOSSARY
abstract model: A model for representing
time-dependent data types
in terms of infinite
sets. For example, a time-dependent point value is represented as a function from time into
point values. This is to be contrasted with
discrete model
.
anonymization: A process that transforms data about a person to prevent the identification
of the person from his/her data.
association rule: A
pattern
that represents relationships between variables that occur
frequently in a data set.
attack model: The capabilities that an
attacker
has to attempt discovering some
sensitive
information
.
attacker: An unauthorized agent who accesses data to infer
sensitive information
about
persons.
cell: In
data warehouses
, the elementary unit of decomposition of a
cube
that contains the
measures
to be analyzed. Each cell is defined by a set of coordinates, one per
dimension
of
the cube. It is also referred to as a fact.
classification: A process that associates an entity to a class from a predefined set of classes.
In
data mining
, rules to classify entities are usually inferred directly from the data through
an automatic learning step.
cloaked algorithm: An algorithm to generate
cloaked locations
.
cloaked location: An area defined for the purpose of blurring the exact position of a
moving object. It is also referred to as obfuscated location.
clustering: A process that groups a set of entities into homogeneous groups, referred to
as clusters, such that entities in the same cluster share a common property, that is, they
are similar with respect to some similarity measure, and are dissimilar (with respect to the
same measure) from the entities in the other clusters.
compact representation: A relational representation of
time-dependent data types
where
each time-dependent value is stored as a single attribute value within a single tuple.
cube: In
data warehouses
, amultidimensional data structure composed of
cells
, where each
cell contains a set of
measures
. Cubes are used to implement
online analytical processing
(OLAP). It is also referred to as a hypercube or multidimensional cube.
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