[Population Index on the Web]

Free-Text Search

The free-text field allows you to search for text anywhere in a citation, including the title, series or journal name, and abstract. This new facility, which was available on an experimental basis for the 1994-96 issues, has now been extended to the entire Population Index database for 1986-99.

Free-Text Examples

Example 1: You are trying to trace a recent paper on segregation that you vaguely recall having seen in the Social Science Quarterly. You enter "segregation" in the subject field and "Social Science Quarterly" in the free-text field. You should find a paper by Doug Massey and Zoltan Hajnal, among others.

Example 2: You type "AIDS" in the subject field and get only two hits. As noted in our discussion regarding searching by subject, this occurs because the actual thesaurus term used is "acquired immunodeficiency syndrome". Entering AIDS in the free-text field yields 715 hits in the period since 1986. The search has now found all citations that include the acronym "AIDS" in the title, abstract, or anywhere else.

Example 3: You type "immigration" in the subject field and get four hits. Entering the same term in the free-text field yields 2,480 hits. Restricting the search to "Canadian immigration" produces 124 citations.

Technical Notes

The free-text index includes every word that appears in a citation as published in the paper or electronic editions of Population Index, a total of 4,060,352 words to date.

The free-text index does not include non-printing fields in the underlying database, such as the subject codes, the geographical codes, or the thesaurus terms. Note, however, that the three fields just mentioned provide the basis for the indexes supporting searches by subject and by geographic region.

A few words about the construction of our indices may help you conduct more efficient searches. Before we index the contents of a citation we remove all punctuation marks. We then index the remaining text, except for a few stop words (including and, or, the, at, by, in, of, on, with) and all single-letter "words" (such as initials). Starting with the December 1996 revision of the search engine, we also remove apostrophes and diacritical marks.

The Web interface follows exactly the same rules, so these procedures should be transparent to the user. We only mention them here so that you will not be surprised when you search for "L'ênquete démographique" and discover that our search engine is looking for the keys "enquete" and "demographique", having stripped the apostrophe, ignored the orphaned L, and transliterated ê and é to e.