HIT: keyword/subject search

[Cindy Curwick <cc120@csufresno.edu>]

Thanks to the many, many dozens of answers I received to my posting.
Most were of the same mind.  In fact, my first 2 answers came back to me
within 10 min. of my posting the question.  I was still online when the
response came back. In essence, this is the response:


Subjects are fixed vocabulary headings attached to documents (books,
periodical articles, websites, etc.)  Keywords are all the words in a
database except those which have been "stopped" (a, an, the, or anything
less
than 3 letters long).

In a library's online catalog, subject searches must match exactly Sears
or
Library of Congress formal subject headings, whichever was used to
construct
the catalog.  With keyword searching a hit is achieved if your search
word is
anywhere in the entry for a book.

There are pros and cons for both search methods.  Subject searching
returns
more exact results, but many of us are not expert enough to be familiar
with
all the formal terminology.  Keyword searching is easier for most users,
results in more hits, but is less exact.

I usually recommend that students try subject searching first when using
a
full-text database like Readers Guide or SIRS.  If their topic is not
used as
a subject heading, then they try it as a keyword, but also may have to
use
Boolean operators to limit the number and relevancy of their results.

This is a difficult concept to teach without providing lots of examples
and
practice.

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"Subject" is part of a controlled vocabulary as used in SEARS
,LC,ERIC,many indexes and in many cases, one's own collection. Keyword"
is
free accesses and searches for the term in any field, any place in
the record. Sometimes they may be used in both ways.
For instance:
Search for sea shells in your library and you may come up with a "see"
or
see also "mollusks if you are doing a subject search.
If a "field" is specified, the computer looks for the term in that
field,
only. In a kw, it looks for it all ober the place.
If you kw search, you will increase the retrieval, and maybe, bu not
necessarily the precision.
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Well, for starts, subject headings are a CONTROLLED vocabulary.
Certainly
library catalogs are an example of controlled vocabulary because they
will
most likely either use Sears of LC Subject Headings.  The indexing of
databases (like those found on CD-ROM products, for example) should use
a
controlled vocabulary (again Sears or LC) or they should, at the very
least, have a thesaurus from which they draw their subject headings.
Those
that don't (or have a poor thesaurus) are seriously limiting to the
user.

On the other hand, databases (both full text and bibliographic) can be
indexed for keyword searching.  That way the user can search any indexed
word (generally that simply eliminates "stop words" - the, with, by, an,
of - etc.) in the record.

Many inexperienced users of keyword (as opposed to subject heading)
think
they have struck gold when they get many hits (searching on the Internet
is just about the best example of that folly) when all they have done is
retrieved records that contain at least one "hit" of their keyword.
Clearly, a record that contains word "X" and a record which lists word
"X"
as a subject are two different things.

In summary, I believe that searching by subject should generally be the
first approach.  If I strike out (especially, if I am unfamiliar with
the
subject itself) I'll do a keyword search and then look to see what
subject
headings have been used for that record.  Then I'll redo the search
using
the correct subject heading.

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--
Cindy Curwick
LMT-in-training
cc120@csufresno.edu