Page 55 - Building Digital Libraries

CHAPTER 3

to expect people to search each one individually; the repository should be
designed so that it can be included in federated searches.
The best way to give users the capability of searching the repository and
other collections simultaneously is to employ a robust metadata scheme that
is applicable to as many different types of resources as possible. Simple but
versatile metadata schemes, such as Dublin Core, are most likely to prove
robust enough to meet the evolving needs of many repositories. Alterna-
tively, the repository should use metadata that can accurately be translated
into Dublin Core or other widely used formats. Be aware that all metadata
schemes, including Dublin Core, have disadvantages. For example, the sim-
plicity that makes Dublin Core easy to use also means that it cannot express
many concepts and relationships, making it unable to meet many needs. It
does not define how data are entered, so the data can be inconsistent even
if the fields themselves aren’t. (Key metadata schemes are covered in detail
in chapter 5.) Particularly complex and nonstandard metadata should be
avoided because generating them is expensive, and they can create compat-
ibility problems when used with other systems or when the time comes to
migrate to another platform.

Crowd-Sourcing

Many users have a knowledge of specific resources that library staff lack.
They may know when and where a photo was taken or be able to identify
the people in it. They may have expertise on documents that allows them to
assign topics more effectively. They may know how to describe data in a way
that makes it more useful for those who need it. Even when they don’t bring
specific expertise, they can provide labor to help with time-intensive tasks.
In addition to these benefits, allowing users to contribute metadata and
descriptive information provides a mechanism for volunteers and others to
engage with collections more directly. However, it’s important to consider a
number of issues before allowing users to contribute metadata:

• How do you convince people to contribute? People already
have many demands on their time, so they need an incen-
tive to participate. Strengthening the collection and improv-
ing access are rewarding, but libraries pay staff for a reason.
The process for contribution needs to be rewarding enough
that people will want to do it. Break ing down tasks into
discrete projects and small, fun steps using games or other
mechanisms may be part of the solution.
• How do you ensure the quality and consistency of contribu-
tions? How do you ensure that the information provided
is correct, in a standard format, and at the right level of
analysis?
To be useful, metadata must be consistent within the
con text of the collection. For example, if three people add
metadata to a collection, and one person provides broad
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