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| Site Search - Advanced Searching |
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You can search our site using two types of searches: simple and advanced. A simple search
is typically a word or set of words that reflect what you're looking for. An advanced search
can employ a number of powerful operators and modifiers to refine the search and get more focused
results.
Although an advanced search can employ operators and modifiers, the disadvantage
is that all aspects of the search must be explicitly invoked. A simple search is
potentially more powerful since it employs operators by default, but will usually return
more results with less focus or accuracy.
When documents are ranked by relevance, they appear in a
list with the most relevant documents at the top.
Our site default is to use simple searches. You can turn on advanced searches by checking the
"Use advanced search" box below to the search text box before you submit your search.
Our site uses the Verity search engine.
Constructing a search expression
Simple searches allow you to enter simple, comma-delimited strings and use wildcard characters.
By default, a simple search looks for words, not strings. For example, entering the
word "All" will find documents containing the word "all" but not "allegorical." You can
use wildcards, however to broaden the scope of the search. "All*" will return documents
containing both "all" and "alliterate." Case is ignored.
You can enter multiple words separated by commas: software, Microsoft, Oracle. The comma
in a simple search is treated like a logical OR. If you omit the commas, the search text
is treated as a phrase, so documents would be searched for the phrase "software Microsoft Oracle."
Ordinarily, operators are only employed in advanced searches. Operators are normally surrounded
by angle brackets < >. However, you can use the AND, OR, and NOT
operators in a simple query without using angle brackets: software AND (Microsoft OR Oracle).
To include an operator in the actual search text, you must surround it with double quotation marks:
software "and" Microsoft (this expression would search for the phrase "software and Microsoft", for example)."
Advanced searches can be constructed using a variety of operators, including
evidence, proximity, relational, conceptual, and score operators.
Most operators in an advanced search are surrounded by angle brackets < >.
You can use the AND, OR, and NOT operators without angle brackets.
Search syntax rules
You can use either simple or explicit syntax when stating simple searches. The syntax you
use determines whether the search words you enter will be STEM'd, and whether the words
that are found will contribute to relevance-ranked scoring.
When you use simple syntax, the search engine implicitly interprets single words as if
they were modified by the MANY and STEM operators. By implicitly applying the MANY
modifier, the search engine calculates each document's score based on the density of the
search term in the searched documents. The more frequent the occurrence of a word in a
document, the higher the document's score.
As a result, the search engine ranks documents according to word density as it searches
for the word you specify, as well as words that have the same stem. For example,
"films," "filmed," and "filming" are STEM'd variations of the word "film." To search
for documents containing the word "film" and its stem words, you can enter the word
"film" without modification in an explicit search, but must use the wildcard format of
"film*" when using a simple search.
When you use explicit syntax, the search engine interprets the search terms you enter as
literals. For example, by entering the word "film" (including quotation marks) using
explicit syntax, the stemmed versions of the word "film", "films," "filmed," and
"filming" are ignored.
The following table shows all operators available for conducting searches.
Search Operators
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< >
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CONTAINS
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PHRASE
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<= >=
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ENDS
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SENTENCE
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=
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MANY
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STARTS
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ACCRUE
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MATCHES
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STEM
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ALL
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NEAR (/N)
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SUBSTRING
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AND
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NOT
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THROUGH
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ANY
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OR
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WILDCARD
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CASE
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PARAGRAPH
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WORD
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Special characters
A number of special characters are handled in particular ways by the search engine. These are
similar to regular-expressions, but used to denote ends and starts of tokens. For example:
Special Search Characters
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Characters
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Description
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, () [
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These characters end a text token.
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= > <!
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These characters also end a text token. They are terminated by an associated end character.
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' @ ` < {[!
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These characters signify the start of a delimited token. They are terminated by an associated end character.
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A backslash (\) removes special meaning from whatever character follows it. To enter a
literal backslash in a query, use two in succession, such as "\\hello world".
Detailed operator syntax
Standard Operators
You can use these operators with phrases and paragraphs:
<ACCRUE> at least one of the words entered must exist to create a match, and the more unique words found, the higher the score.
<AND> all words must exist in each document to be considered a match.
<OR> any one of the words can be found to create a match (at least one).
<PHRASE> the words must occur in the same order entered.
<SENTENCE> the words must occur in the same sentence to match (any order).
<PARAGRAPH> the words must occur in the same paragraph to match (any order).
<NEAR/3> the words must occur within three words (or any number entered) to be considered a match.
<NEAR> the words must occur in the same document and the closer the proximity (any order), the higher the score.
<ALL> all of the words must exist.
<ANY> any of the words can exist.
To use the word combination operators, enter the first word or phrase, then the operator, then another word or phrase. The search engine will search for both the preceding and following word or phrase according to the operator rule.
Example: gorbachev <AND> yeltsin
Retrieves documents containing both "gorbachev" and "yeltsin".
Example: triangle <SENTENCE> bermuda
Retrieves documents containing "triangle" and "bermuda" in one sentence (in any order).
Example: vacuum cleaner <OR> hoover
Retrieves documents containing the phrase "vacuum cleaner" or the word "hoover".
Example: hoover <AND> vacuum cleaner
Searches for documents containing "hoover" and the phrase "vacuum cleaner".
Example: mechanism <near> group
Finds pages where "mechanism" is on the same page as "group", ranked by proximity
Example: mechanism <near/5> group
Finds pages where "mechanism" is within 5 words of "group"
You may use more than one of these operators in a query. Most operators require that you place angle brackets ( < > ) around the operator to clearly distinguish its meaning. Default operators and modifiers do not require that you add angle brackets; <AND> and <OR> are assumed to be operators and <NOT> is assumed to be a modifier when used.
We recommend keeping your operator combinations fairly simple. Simple combinations produce more predictable results, and ensure that the search engine will be able to read the combinations.
Here are some examples of operator combinations:
Example: cousteau <AND> whale <SENTENCE> spawning
Retrieves documents containing the word "cousteau" and a sentence including both "whale" and "spawning".
Example: poland <PARAGRAPH> walesa <AND> socialist
Retrieves documents containing "poland" and "walesa" in the same paragraph, and the word "socialist" anywhere
Example: president clinton <AND> no <SENTENCE> tax hike
Searches for documents containing "president clinton" and a sentence including the word "no" and the phrase "tax hike".
Example: dark <AND> dangerous <AND> deadly
Retrieves documents with all three words.
Note that it is generally easier to use the comma between search words if any one of them should be considered a match. Queries automatically search for any word occurence when the words are separated by commas. "Ransom <OR> Kidnapping <OR> hearst" collect the same documents as "ransom, kidnapping, hearst", but document scores can differ because the use of the comma specifies the <ACCRUE> operator. Accrue considers each word evidence of your subject, and gives documents a higher score when more evidence exists.
Word Operators
You can use these operators for a single word:
<WORD> find the exact spelling (no variations). You can also double quote the search word to indicate this rule. <WORD>computer is the same as "computer" and both match specifically on this word with stemming for other endings like computers, or computed.
<STEM> find all standard variant endings for the stem (this operator is Verity's default search rule). You can also use a single quote to indicate this rule.
<WILDCARD> find all words with the string, including anything before or after the asterisk (*) or character (*), were the operator appears.
A word operator applies to the single word which immediately follows it. To use a word operator, enter the operator first, then the word. For example:
<WORD> consistency
<WORD> darkness
<WORD> visible
The search engine's default search rule is <STEM> (all standard variant endings for the stem). So you don't have to enter the <STEM> operator when you want a stem-based search.
With the <WILDCARD> operator, you must include an asterisk either at the start or end of the word where you want all other matches. For example:
Example: <WILDCARD> syncopat*
Retrieves "syncopation", "syncopate".
Example: <WILDCARD> *down
Retrieves "breakdown", "meltdown", "down".
You may combine word operators with word group operators.
Example: kidnap <AND> <WORD> ransom
Retrieves documents with "kidnap" ("kidnapping", "kidnapped") and "ransom".
Example: <WORD> violin <SENTENCE> play
Retrieves documents with a sentence containing both "violin" and "play" ("playing", "played") in any order.
Example: <WORD> fancy <AND> <WORD> hat
Retrieves documents containing both the words "fancy" and "hat" (this query would not retrieve a document containing only "fancy" and "hats").
Field Operators
You can use these operators with fields like DATE or AUTHOR:
= must be equal to the entered value
> must be greater than the entered value
>= must be equal to or greater than the entry
< must be less than the entry
<= must be equal to or less than the entry
<STARTS> must start with the entered value
<ENDS> must end with the entered value
<CONTAINS> must contain the token entered
<THROUGH> retrieve anything between the two values entered including those values
<MATCHES> matches a character string exactly
<SUBSTRING> must match the string anywhere
The fixed field operator must precede the search value. For example:
<STARTS> wall
>= 4000
<ENDS> 91
The default search value for fields is <CONTAINS>. If you are looking for a field containing your value (and the field may have anything else in addition) you don't have to enter an operator.
When you use <THROUGH> to request a range of values, you enter both start and end values. You may enter <THROUGH> either at the beginning of the field, and list start and end values after (separate them with a space), or enter <THROUGH> between the start and end values.
Example: 01/15/89 <THROUGH> 09/15/91
Searches for documents dated January 15, 1989 through September 15, 1991.
Example: 01/01/91 <THROUGH> 09/30/91
Searches for documents dated January 1, 1991 through September 30, 1991.
Using Modifiers
Modifiers modify the operator search rule, generally adding an additional level of detail. Use them to increase the accuracy of your queries.
<CASE> find exact upper/lowercase spelling as entered in the query
<MANY> count occurences of this word or phrase in a document, and assign a slightly higher score for more occurences based on the density of the document
<NOT> exclude documents with this word, phrase, or value (the <NOT> modifier will also retrieve all documents that do not contain the search value)
Rules for Adding Modifiers
A search word or value must have an operator in order to use a modifier. Since Verity assumes an operator of <STEM> for words and <CONTAINS> for fixed field values, you can use a modifier by itself. Verity assumea a default modifier of <MANY> for word searches. The modifier is placed directly in front of the word or operator.
You can use <CASE> with single words (with or without a word operator) or for fixed field values if the field accepts upper and/or lowercase letters combined. <MANY> can apply to single words and to phrases. <NOT> applies to any word, phrase or topic.
Example: <CASE> Japan
Retrieves documents with the word spelled "Japan".
Example: <MANY> wall street
Assigns slightly higher scores to documents using the phrase "wall street" many times.
Example: gorbachev <AND> <NOT> yeltsin
Retrieves documents with "gorbachev" excluding any which also contain "yeltsin".
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