Electoral-Management-Reference-Model-v.1.0

In spite of all of this complexity, there must be one active record and physical address for each
registered elector in the database to ensure the fundamental principle of one person one vote. To
identify matches, some agencies use deterministic matching algorithms, others use probabilistic
algorithms, and others rely extensively on manual reviews (see Matching Algorithms text box).
Regardless of the type of matching system
used, agency staff who are trained in how to
find and consider the information necessary
to determine whether two or more records
represent the same elector are involved in
reviewing records that are not automatically
matched.
After the matching processes are complete,
the appropriate transactions are applied to
the register. If the new data matches an
existing record in the register, the transaction
may be an update, a confirm, or a remove.
When no match is found, the elector record
is added to the register as a new elector.
Records with multiple matches are reviewed
manually. A history of transactions may be
maintained in the register, including the date
and source of new information for each
transaction.
In the case of registration data from other
electoral agencies, transactions cannot
always be applied immediately. For
instance, if there is uncertainty about
Matching Algorithms
Deterministic matching uses a combination
of algorithms and business rules to determine
when two records match. The match is
determined by the satisfaction of one or more
business rules. Deterministic matching
systems do not scale well because, for
instance, if a new attribute is added, the
number of business rules multiplies and
system performance may be affected. This
approach is best suited to situations where
exact matches are anticipated and the number
of records is relatively small.
Probabilistic matching uses likelihood ratio
theory to assign a probability of a match (e.g.,
76% likely to be a match). Agencies can set
their own thresholds for probabilities that
correspond to an automatic match and a range
of probabilities that should be manually
reviewed. These approaches are best suited
to systems where the number of attributes is
high and the datasets are large.
whether an elector meets a local residency requirement, the transaction may not become active
until after the residency period has been satisfied. In B.C., new registrations from the National
Register of Electors become active after six months, which is the B.C. residency requirement
under local legislation.
Register Maintenance also involves running checks to ensure the integrity of the data in the
register of electors. The ability to produce custom reports to identify subsets of elector records
that satisfy specified criteria is very important. For instance, a report that identifies elector
records that have not been updated in the last ten years may be helpful in identifying records that
should be set to ‘inactive’. Reporting is also an essential part of identifying and correcting data
irregularities, such as records with missing birth dates, or electors whose age falls outside of an
acceptable range (e.g., over 100 or under 18).
Sometimes mailings are conducted to subsets of elector records suspected of being out-of-date.
When mail is returned to the agency as undeliverable, the information is used to update the
register. The register of electors is often used as a source of custom mailing lists for elector
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April 9, 2010