CDOT Performance Data Business Plan - Cambridge Systematics

Appendices
for the development of data standards for data definitions, means of
collection, and format.
Data Assessment
In order to support performance measurement efforts effectively, data programs
must be carefully evaluated in terms of their ability to meet overall agency and
stakeholder goals. For example, traffic and safety data programs must produce
quality data to support decision-making regarding safety and mobility projects.
The section assists in performing a health assessment of data systems to
determine where the most critical deficiencies exist and to develop a strategy for
addressing those deficiencies.
In general, criteria must be developed to assess the data programs. An example
of the type of criteria that could be used were initially identified for use with the
FHWA’s Traffic Data Quality Management Report and are applicable, as well,
for assessing quality of data used for performance measurement. These criteria
include the following:
Accuracy. The measure of degree of agreement between data values or sets of
values and a source assumed to be correct. It is also defined as a qualitative
assessment of freedom from error, with a high assessment corresponding to a
small error.
Completeness (also referred to as availability). The degree to which data
values are present in the attributes (e.g., volume and speed are attributes of
traffic) that require them. Completeness is typically described in terms of
percentages or number of data values and measures how much data is
available compared to how much data should be available.
Validity. The degree to which data values satisfy acceptance requirements of
the validation criteria or fall within the respective domain of acceptable
values. Data validity can be expressed in numerous ways. One common way
is to indicate the percentage of data values that either pass or fail data
validity checks.
Timeliness. The degree to which data values or a set of values are provided
at the time required or specified. Timeliness can be expressed in absolute or
relative terms. This also can be referred to as latency.
Coverage. The degree to which data values in a sample accurately represent
the whole of that which is to be measured. As with other measures, coverage
can be expressed in absolute or relative units.
Accessibility (also referred to as usability). The relative ease with which
data can be retrieved and manipulated by data consumers to meet their
needs. Accessibility can be expressed in qualitative or quantitative terms.
Data Management
While managing data within data programs, it is important to do the following:
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