Information Technology Reference
In-Depth Information
A man doesn't know what he knows until he knows what he
doesn't know.
Figure 6.2
Thomas Carlyle.
Reveals Levels of Ignorance
Thomas Carlyle (Figure 6.2) said, “A man doesn't know what he knows
until he knows what he doesn't know.” The information systems that we
design and build deliver “what we know.” They rarely take the trouble
of identifying what we do not know.
This omission makes our information systems incomplete — not only
in some theoretical meta-information sense, but in their practical useful-
ness. By ignoring the information that is excluded, the reports that we
generate from our systems, formal, well formatted, and correct as per
some logic, remain incomplete in an informational sense. Although there
may be valid reasons why some information is excluded, the most obvious
being that it is not available, what is required, however, to satisfy Carlyle's
dictum is that this exclusion or omission must be identified as such by
the provider in a manner recognized by the consumer. The reader of the
report must not only know what one
is
getting, but also what one
is not
getting. Take a look at the example below.
Managing Information
Reconciling Multiple Sources of Information
The first issue that comes to mind when one thinks of multiple sources
of information is reconciliation. Attempts to reconcile data from two
sources can be difficult. The problem is often at the metadata level. If
one report shows the number of employees as 120 and the other as 118,
then the difference is most probably in the definition of “employee” —
it is possible that the latter does not count as employees those who are
on extended leaves of absence. Data dictionaries and metadata repositories
are attempts to tackle the problem at this level. Can we have one definition
of employee throughout the company please?
Classification of Data
Companies have policies regarding the classification of data. This may be
for security reasons, for retention reasons, to implement backup policies,
and to support many other objectives. The classification and the action
