Databases: Subject and Thesaurus Browsing
Information Literacy GEO this assignment addresses:
Evaluates and selects information. Retrieval of a large number of records from research databases overwhelms students when they want to identify and select those records that are most relevant to their needs. By demonstrating the subject or thesaurus browsing features of databases, the student will to learn how to progress from quantity of the search results to quality records effectively and efficiently.
Objectives of assignment:
- Students learn retrieving the most relevant information with the least effort.
- Students perform information retrieval effectively and efficiently after they understand the difference between keywords and theaurus/subject terms.
- Students learn to refine their search results.
This exercise requires the use of a computer lab for hands-on computer instruction. The instructor should prepare and test a list of the terms (about 10 terms) that are appropriate for the database of your choice. Ambiguous terms that yield a large amount of irrelevant hits are ideal.
This module is intended to demonstrate how to do a sure search by using the subject or thesaurus utility of the databases. It will work best with the databases that have subject or thesaurus browsing capabilities. Academic Search Premier and CINAHL are good examples of such databases. The instructor will explain the differences between keywords and subject terms while comparing and demonstrating them on an appropriate database. A good method to achieve this part is to ask the class to suggest words that can have different meanings, and may even be used as proper names of persons, places, etc.
An example is Rosemary (as an herb and a proper name). Search for rosemary (herb) by entering it as a keyword in the search box. Attract the students' attention to the number of hits, and a record where Rosemary is used as a personal (proper) name. Now, use the subject headings or thesaurus section of the database and browse for rosemary. Ask students to explain the difference in the precision and quantity of the search result in keyword searching and subject browsing.
Assignment: Database Subject and Thesaurus Browsing
- Divide the students into two teams and ask each team to pick a spokesperson.
- Call one team subject group, and the other team keyword group.
- Give the same list of the selected terms to both teams.
- Ask the subject group to use the subject browse of the database and record number of hits for each term on the list.
- Ask the keyword group to enter each term from the list as a keyword in the search entry box of the database and record the number of hits for each keyword.
- On the blackboard (or any other group demonstration tool) draw three columns with these headings:
- Number of Keyword Hits
- Number of Subject Hits
- Write the list terms in column a.
- Ask the subject, and keyword spokespersons to read the number of hits for each term on their list (one term at a time).
- Enter the number of hits for each subject and keyword search in front of each term in columns b, and c.
- Compare the numbers of hits for each term.
- Select a few summary records (title, author, descriptors/subjects, and abstract) from the keyword group's hit list where the term they have entered as keyword is not used in the same sense as they had been looking for. For example, show them how searching for rosemary as an herb has resulted in an article where Rosemary is used as a personal name, or in the title of a song, etc.
Important summation/review points:
- After comparing the subject and keyword results, students will become aware that:
- An efficient and effective search can be accomplished by using pre-coordinated database utilities, such as thesaurus or subject browse lists.
- Search terms (keywords) may represent different concepts and ideas that may not deliver the exact information they are looking for.
- The core concepts of the articles, books, etc., are listed in the subject list or thesaurus of each database.
- Students should be reminded to look at a sample of the summary records for more subject terms that they can find in each record that would further refine their search results. For example, ask them to find articles with both rosemary and medicine (or medicinal use) in the subject list of the summary record.