eHRAF Tutorial

     

last updated January 26, 2003

 

1. INTRODUCTION
-
Getting Started
-Instructions
-Background
-Browse & Search

 

Text Search

Overview

Searching the eHRAF ethnography database is both more powerful and more complex than a traditional web search.  It is likely you are used to doing keyword searches, where you type in a word or words, and then sort through hundreds or thousands of “hits” to find what you are looking for.  These kinds of searches require little work to get results, but then lots of work to go through those results to find meaningful information.  eHRAF searching is almost the inverse of that system; setting up an effective search takes some time and thought, but doing so will give you much better “hits.”  The difference is that, while you can become more proficient and faster at setting up effective searches in eHRAF, other search engines never learn to give you more intelligent results.   

Figure 10: Text Search Page - Click to see image

In order to search eHRAF effectively, it helps to know the kinds of information available and how it is organized.  As mentioned before, most of the documents in eHRAF are ethnographies, meaning that most cultural information will be about a single culture, rather than a group of cultures.  Thus, you are likely to find documents that describe herbal remedies among the Blackfoot, but you are not likely to find documents about herbal remedies among Native North Americans. 

Also, as we mentioned in earlier, it is important to understand that the documents in eHRAF are indexed with OCM Subject Codes at the paragraph level.  Unlike other search engines that search an entire text as one unit, eHRAF searches millions of individual paragraph units across hundreds of thousands of documents.  If you search for more than one word, the eHRAF search engine will usually look for paragraphs that contain both words. 

Finally, while you will see a second option in the Search feature (eHRAF Source Bibliography), we will only be learning about the Text Search in this tutorial.

Text Search Sections: OCMs, Words/Phrases, and Cultures

There are three parts to an eHRAF search: OCM Subject Codes, Exact Word or Phrase, and Culture/OWC.  In designing a search, you may use any, a combination, or all of these sections to find information.  However, for the purpose of this tutorial, we will most often be working with each section individually.  Also, further information on each search section is available by clicking on “Help” in the section’s title bar in the eHRAF database.

Boolean Operators (and, or, not)

In both the OCM search and the exact word or phrase search, there are drop-down boxes with the Boolean terms “and,” “or,” and “not.”  These terms can either restrict or expand your search, as described below:

And means both OCMs/terms must be present >> restricts a search

Or means either OCM/term must be present >> expands a search

Not means an OCM/term must not be present >> restricts a search

By using multiple search sections simultaneously, you are automatically using the “and” term and limiting your search.  Thus, you will find more documents simply searching for the OCM code 773 (mythology), than if you search for the OCM code 773 and a word such as “wolf.” 

Search Examples

As an example, we will be searching for the following information:

1) a culture from the Northwestern Plains of the United States (region)

2) mythology (major subject)

3) the wolf as a mythical creature (narrower area of major subject)

From your experience with the Browse function of eHRAF, you have already found at least one document that has the information on mythology we are looking for (The Sun God’s Children).  This knowledge will help you evaluate the quality of various search approaches.

Additional Information

Terms: eHRAF, ethnography, OCM Subject Codes, Source Bibliography

         

 

2. BROWSE CULTURES
-
Overview
-The A-Z Index
  -Instructions
-Browse by Region
  -Instructions

 

3. CULTURE PROFILE
-
Overview
-File Description
-Cultural Summary
-File Evaluation & Indexing Notes

 

4. DOCUMENTS
-Overview
-Looking at Documents
-OCM Subject Codes
-Instructions

 

5. BROWSE SUBJECTS
-Overview
-A-Z Index
  -Instructions
-OCM Subject Category
-Major/Sub-Categories
-Browse Subjects
  -Instructions

 

6. TEXT SEARCH
-Overview
-Sections
-Boolean Operators
-Search Examples

Word/Phrase Search
-Overview
-Instructions
OCM Code Search
-Overview
-Instructions
Other Searches
-Culture/OWC Search
-Combining Searches
  -Multiple Sections
  -Multiple OCMs
-Instructions
-Searching for Graphics