Electronic Databases
Searching for Periodical Information - Pt. 2
Looking for articles is going to get a lot easier this week. Instead of thumbing through
paper index volumes year by year, you'll be searching electronically. There are several
advantages to electronic databases, and knowing how to use the the vocabulary and access
points of general and subject specific databases will help you target your search for
periodical information.
WHERE WERE HEADING
in our search for periodical articles
Where weve been
PERIODICAL STACKS
Last week you needed to find an article from a magazine or a journal on a particular topic. So, you went to the library and wandered around until you saw a journal that might be related to our topic. Then you flipped through it and maybe found an article of interest.
As you know from experience, this is a very inefficient way to look for articles, but some students really do it this way! You only needed one article on a very broad topic, e.g. earthquakes. Imagine if you needed 7 articles, not simply on earthquakes, but on engineering methods that help buildings remain standing during an earthquake! Finding these articles by roaming the stacks could be a very long-term project.
PERIODICAL INDEXES (IN PRINT FORMAT)
After your random search you quickly learned about periodical indexes, such as the Readers Guide to Periodical Literature, which allow us to look up a subject and find a list of articles from different periodicals on that topic.
This approach is MUCH better than roaming the stacks, but it is still time consuming. For example:
In our fast-paced, 21st century life, there must be a better way
REFERENCE DATABASES (COMPUTERIZED PERIODICAL INDEXES)
Fortunately, most periodical indexes are now available in electronic format, either on the Web or on CD-ROM, which makes searching for articles much easier and faster.
As we look more closely at Reference Databases over the next couple of weeks, remember that Reference Databases are the same thing as periodical indexes in book format - they have just been given an electronic, searchable interface. In many cases the online versions of an index correspond exactly to a book-like index that is in print format. For example, we have the MLA Bibliography on the Web as a reference database, and we also have a paper index titled MLA Bibliography in the Reference stacks.
Computerized reference databases have three main advantages over traditional print indexes:
1. Many years of articles can be searched at once. For example, I can do a search on airplane hijackings and find articles from 1985 to 1995 in one search.
2. Two or more search terms can be combined. This results in a more sophisticated search then just looking up a subject in a print index. For example, in the Readers Guide we looked for articles on one topic or subject heading. What if we wanted articles with more focused topic, such as the effects of exercise on preventing cancer? In a reference database, we could type something like exercise AND cancer and come up with a list of related articles.
3. Finally, reference databases allow searching by a greater number of access points. An access point is a way to access information in a catalog or index. For example, in the HELIN catalog, we can search by author, title, subject, call number, etc. All of these are access points. In the Readers Guide one can search by subject or author only. In a reference database, you can search by author, title of article, subject, title of periodical, date published, and so on. This allows you to run more powerful and precise searches.
There are many general and subject specific reference databases available to us at URI. From the URI Libraries homepage find and click on the link for "Reference Databases." You'll come to a page that lists major disciplines of knowledge (Arts, Business, Health Sciences, etc.) Each link will connect to a list of electronic databases, most of which are subject specific and fall in a subject category, and some are general and cover all topics. Some index only scholarly journals, while others cover all types of periodicals.
Go to "All Databases by Title." Note how many databases URI has.
Also, like indexes such as the Readers Guide, URI doesn't make these databases - we buy them from companies that provide access to them for a fee. Many are quite expensive, over $10,000 per year. Most are less, about $5-6,000 per year.
Academic Search Premier
Academic Search Premier is a general database and can be found from the URI Libraries homepage by clicking on "Reference Databases" then "General & Reference." Read the description.
You'll see that Academic Search Premier:
Click on the link and try to do a little self-exploration:
Basic Search (refer to your Search Strategy Work Sheets from previous assignments) Separate different concepts with AND smoking and depression. You can use OR (smoking or nicotine) and depression
Limit Your Results
Below the search box there are several limiting functions you can use before you conduct
your search:
Searching
Do a simple search on your topic - type in your term(s) and click the "Search"
button. Hopefully, you'll come to the Results List, listing the articles that ASP found
using your terms.
Results List
Search results are listed 10 on a page. The total number of "hits" or records
retrieved is shown at the top of the list with links to additional pages. Each short entry
includes the citation to the article as well as other information about the availability
of each article, such as "Full Text," "Full Page Image" (Adobe Acrobat
PDF file), "Search HELIN" or other notes.
NOTE: Dont disregard non-full text over full text the number of full text articles is based on agreements between publishers and the database vendor, not on the quality of the article. Whats included and what isnt is arbitrary.
Seeing Results
Click on an article and look at the record. It will consist of several "fields"
- the Title, Subject, Source, Author, Abstract, other identifying terms, and (maybe) the
full text of the article.
The citation includes all the information you need to find the article (and to cite it in your paper's bibliography or your final project for this course.) The citation is made up of several parts - title, publication, date, author, volume. issue, page numbers, standard number and subject terms (some publications include some other fields).
Look at the field entitled "Subject(s)." Is one of your search terms listed there? This field can come in very handy when you are searching for articles on the same topic. The Subject field uses the database's "controlled vocabulary" (discussed below) to identify what the article is about. You can click on any of these terms and bring up another set of articles on that topic.
Can you tell if the articles are from popular or scholarly journals? Review the differences from earlier lessons to help you figure it out. In Academic Search Premier you can limit your search to just scholarly journals right from the search page. Click on the box next to "Peer Reviewed" and conduct the search.
Most articles have an abstract, a few sentences describing what the article is about. If available the full text will follow the abstract (if available).
On the top of the screen you will see buttons for printing, saving and e-mailng the article. The print function turns the record into a printer-friendly version and the e-mail link will allow you to send the entire article.
You can get back to the results list by clicking on the "Result List" button in the menu near the top of the page. You can also Mark the articles you are interested in by clicking the little box next to each article on the list (or in the record itself) and retrieve them by clicking on the "Print," "Save" or "Email" buttons.
Finding Articles Using Citations
Some of the articles in Academic Search Premier will only have a citation and an
abstract. (Also, very few of the other electronic databases provide full text of
articles.) To find the text you'll have to find the journal in the library. This requires
a search for the journal in the HELIN Catalog.
If there is a "Search HELIN" link, click on that and it will search the catalog for you. Otherwise, go to HELIN and "Restrict Your Search" to the "Journals/Serials Collection" and do a Title search for the title of the JOURNAL. (You cannot find individual articles in the HELIN catalog.) There you will find the record for the journal including the Call Number (that's how you will find it on the shelf) and information on which volumes the library has (compare what the library has to the volume and issue number listed for your article).
For more information, consult the URI User Guide, Searching for Periodicals in HELIN.
Advanced Searching
Now that you've seen how articles are indexed in a database like Research Library, it's
time to use some of the powerful search strategies that the indexing allows.
ACCESS POINTS & FIELD SEARCHING
An access point is a way of searching using an information tool. Each access point is one part of a database record that provides access to the whole record, for example, title and author are access points when searching the HELIN library catalog.
The most common access points are author, title, subject, and keyword, but reference databases often allow searching by many additional access points.
To help understand access points, imagine that you are building a database of your CD collection. In the database, you want to include every possible piece of useful information about each CD, such as:
Each of these bits of searchable information, or access points, would be placed in a
different field of your database record.
If you included all of this information, you could set up your database so that you could search by any of these fields, or a combination of them, for example you could search for every CD by a particular artist during a specific range of years.
Searching by different fields can also yield different results. For example, searching for Hemingway in the author field of a library catalog will find books by Hemingway. Searching for Hemingway in the subject field will find books about Hemingway.
To see how field searching by different access points works, well use Academic Search Premier as an example.
CONTROLLED VOCABULARY
Just like library catalogs use Library of Congress Subject Headings, reference databases use controlled vocabulary to index articles. That is, they use designated words or phrases, sometimes referred to as descriptors or subject terms, to consistently describe the topics of articles. This makes searching for articles more effective and precise. Just think, if you were making that database of your CDs discussed above, you would want to use the same words to describe types of music so that when you searched youd get all the relevant records with one search. For example, when you enter your Rap CDs into the database, you will want to decide whether you are going to call them Rap or Hip Hop. If you are not consistent and later you perform a search for all of your Rap CDs, you are going to miss the ones that you had categorized as Hip Hop.
Each database has its own unique controlled vocabulary. These terms are often based on
the specialized terminology of the subject area covered by the database, for example:
business, economics, zoology, medicine. This vocabulary of subject-specific databases is
often very focused much more so than the Library of Congress Subject Headings or
the subject headings of general databases. For example, for the topic allergies:
Database |
Subject Heading |
|
| Library of Congress Subject Heading (Academic Search Premier) | Library catalogs & some databases (ex., ASP) | Allergy |
| ProQuest Direct subject heading | Research Library | Allergies |
| Medical Subject Heading | MEDLINE (PubMED) | Rhinitis, allergic |
Such focus makes it easier to find subject-specific information. Most databases have thesaurusi with which you can check your subject keywords and find out what the databases controlled vocabulary for your subject is.
STOP WORDS AND PHRASE SEARCHING
So far, we have learned that before searching the library catalog or a reference database, we first identify our main concepts, list keywords that describe each, and separate the different concepts with the word AND, for example smoking AND depression. In general, if we do not separate our concepts with AND, instead typing in words in succession, or even a sentence, the database will not interpret our query correctly. For example, if I type in what is the connection between smoking and depression? or I type smoking depression, I will not get very good results.
While it is true that some databases are getting smarter and know how to break apart a sentence (for example Britannica Online or the web search engine Ask Jeeves), in general it is not a good idea to search like this.
Every database has different rules about how they interpret what you type. Some will ignore certain words altogether these are called stop words, and are usually very common words that would take up too many system resources if the database were to search for them. Others will allow you to search for two words together as a phrase, but will break apart any phrase you type that is longer than three words. It is a good idea to understand how the database you are using works before searching. This information is typically found in the Help screens.
BOOLEAN OPERATORS
Boolean, or logical, operators let you combine multiple search terms into a single search statement by using the connector words AND, OR, and NOT.
AND
Boolean concepts are often explained with Venn diagrams circles which represent sets of data containing the specified terms.
For example:
Search = smoking
This set of search results contains information only on smoking.
Search = depression
This set of search results contains information only on depression.
Search = smoking AND depression
This set of search results will find information on both smoking AND depression. This
essentially says, I want to find information on the connection between smoking and
depression.
Using AND can be confusing, because people often think that the word and
means to add things together to make a larger whole, however using AND actually narrows
your search and gives you fewer results.
OR
Search = smoking or nicotine
This set of search results will find information on either smoking OR nicotine. This says,
I want to find information on smoking or nicotine either word is relevant to
my topic.
Using OR can be confusing, because people often think that the word or
means to choose only one thing among many to make a smaller whole, however using OR
actually broadens your search and gives you more results.
NOT/AND NOT
Search = smoking NOT marijuana
This set of search results will find information on smoking but NOT marijuana. This
essentially says, I want to find information on smoking, but not about smoking
marijuana.
You have to be careful using NOT. The article's title or abstract may mention marijuana
anyway, saying it is not the focus of the article, but that smoking cigarettes is. The
article may be relevant to your search, but it will not be retrieved using the terms,
"smoking NOT marijuana."
COMBINATIONS
Search = (smoking OR nicotine) AND depression
This set of search results will find information on either smoking OR nicotine combined
with (AND) depression. This says, I want to find information on the connection
between either smoking or nicotine (because theyre pretty much the same thing) and
depression.
PRECEDENCE AND PARENTHESES
Most databases observe a hierarchy or precedence with respect to operators. For example, the OR operator may be processed first in some databases; the AND operator in other databases.
Consider this:
If the AND operator is processed first, the search statement dogs OR cats AND leashes will find records that contain both cats and leashes or articles just about dogs.
If the OR operator is processed first, this search statement will find articles about either dogs or cats combined with the concept of leashes.
Note the difference.
To get around this ambiguity, always group in parentheses the parts of the search statement you want processed together. This is often referred to as nesting.
So, if we want an article about the use of leashes on either dogs or cats, we would structure the search as (dogs OR cats) AND leashes. We could include a related concept for leashes and expand the search like this: (dogs OR cats) AND (leashes OR harnesses).
PROXIMITY OPERATORS
Proximity operators are similar to Boolean operators. Proximity operators allow you to specify the relationship between multiple search terms by using the operators W and N. They are most useful when searching the full text of an article.
W (WITHIN)
N NEAR
TRUNCATION & WILDCARDS
TRUNCATION CHARACTER
Most databases specify a character that can be used to search for words containing a common word root, with any number or combination of characters following the root.
The truncation character in Academic Search Premier is "*"
For example, operat* will find records containing operations, operational, and operator.
Truncation can be useful when you dont know whether or not your search term will appear in the singular or the plural, for example wildcat* will find wildcat or wildcats.
WILDCARD CHARACTER
Most databases specify a character that can be used to search for a specific number of characters, in any combination. You use one wildcard character for each character that youre unsure of.
The wildcard character in Academic Search Premier is "?"
For example, wom?n will find records containing woman, women, and womyn.
All of these advanced searching techniques can be helpful in
streamlining your search for information. Once familiar with them, each researcher
develops his or her own set of preferred search strategies.
Provided that you are using the techniques correctly, there is no right or wrong way to search. The most important aspect of your search is the quality of the results you retrieve are you finding information on your topic? Are your results precise, that is, is the information you found focused, or is there a lot of junk mixed in with the relevant information? The ideal search is one that is narrow enough to exclude extraneous or unrelated articles yet broad enough to include the most relevant articles.
You should continually keep an eye on the quality of your search results and adjust your search strategy accordingly. This means you should:
NOTE: the Help feature available in most databases can
explain to you how to make the most of the database, thus ensuring that your searches are
efficient and your results are on target.
This course was developed by Joanna Burkhardt, Mary MacDonald and Andrée Rathemacher and was adapted for online use by Jim Kinnie as part of the URI Libraries Plan for Information Literacy - http://www.uri.edu/library/instruction_services/infolitplan.html
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