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Search Tips for Online Public Access

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What does OPA search?

The Online Public Access (OPA) prototype provides a centralized, streamlined means of searching multiple National Archives resources at once. The OPA prototype allows you to search all of the catalog records and authority files from the Archival Research Catalog (ARC), records from the Electronic Records Archives (ERA), and all of the web pages from Archives.gov and the Presidential Libraries. The system illustrates a streamlined search experience for users.

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Keyword Searching

You can enter one or more keywords in the basic search box. The system will retrieve the results as applicable from ARC, Archives.gov, and the Presidential Libraries and present them together in OPA.

The Advanced Search gives you additional search options to narrow your search. At the top of any screen in OPA, there is an Advanced link directly to the right of the search box. See Advanced Search for more information.

The following is a Quick Reference for the most common types of search expressions and operators you can use to refine your search.

Search Expression Search Results
Harry Truman Finds results where both the term Harry and the term Truman are present. There is an implicit AND between the words entered. They do not need to be next to each other and they do not need to be in the order specified.
Harry AND Truman Finds results where both the term Harry and the term Truman are present.
Harry OR Truman Finds results containing either Harry or Truman, such as Harry Harrison, Truman K. Gibson, Harry Truman.
"Harry S. Truman" Finds results containing the exact phrase Harry S. Truman or Harry S Truman (punctuation is ignored), but not Harry Truman.
(Harry Truman) AND Captain Finds results where Harry S. Truman or Harry S Truman is found exactly and in that order (punctuation is ignored), and the word Captain is also found somewhere in the same result, such as Harry Truman, 129th Field Artillery Captain.
Truman NOT Harry Finds results containing Truman but not including Harry, such as Truman K. Gibson, but not Harry Truman.
(Franklin OR (Theodore NOT Teddy)) AND Roosevelt Finds Franklin Roosevelt and Theodore Roosevelt (as long as there is no reference to Teddy Roosevelt).
bal* Finds ball, balance, ballast, balderdash, etc.

If you enter more than one word in the keyword search box, and none of those words are search operators, then your search results will include results that contain all the words (the words are automatically combined using the AND operator).

An operator is a reserved word with a special meaning, such as AND, OR, NOT. The results of the search will change depending upon when and where you use an operator.

Double quotes are used in exact phrase searching. Parentheses are used to group search terms and imply precedence. The wildcard character is used to expand a search term.

Punctuation is ignored in keyword searches, except for apostrophe–s (’s). For example if you search Kennedy’s this will only find results containing Kennedy’s, not Kennedy.

Stop words are ignored on all types of searches. These are common English–language words (e.g., a, are, by, the, etc.) that are dropped from the search in order to help improve system performance.

Diacritics are also ignored on all types of searches. Search terms containing diacritics (e.g., ä) will find references containing the word as you entered it, as well as words containing the nearest basic equivalent letter.

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Exact Phrase Searching

Exact phrase searching limits your search to multiple terms in the precise order specified. For example, searching for "south east asia" will only find results that include those three words side by side and in that order.

You can specify exact phrase searches in any of the free text search boxes by enclosing the phrase in double quotes " ". For example, when you enter "Harry Truman" in the main keyword search box, your results will only include results where the words Harry and Truman appear together, in that exact order. In this example you will not retrieve Harry S. Truman.

If you enter an operator inside of the double quotes, then the operator is treated like a regular word, and the search is based on an exact phrase match. For example, if you enter the exact phrase "Harry and Truman", your search will include results where the three words Harry and Truman appear (all together and in that order).

If you enter more than one exact phrase, and you do not include an operator, then your search will include results where both exact phrases are found. For example, if you enter "Harry Truman" "Jackie Kennedy", your search will include results where both Harry Truman (together and in that order) and Jackie Kennedy (together and in that order) appear. However, if you enter "Harry Truman" OR "Jackie Kennedy", your search will include results that have either Harry Truman or Jackie Kennedy or both.

If you enter an exact phrase plus one or more other words, and you do not include an operator, then your search will find results that include both the other word(s) and the exact phrase. For example, if you enter Truman "Jackie Kennedy", then this is interpreted as Truman AND "Jackie Kennedy".

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Wildcard Searching

Search terms can include a wildcard at the end. The wildcard character is the asterisk (*). For example, to retrieve results that contain the words child and children, enter child* in the search box.

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Stemming

Online Public Access performs stemming on search queries. Stemming is used by search engines for search expansion. The search engine looks for the root of the word (e.g., fish), and then finds other words that match that same root (e.g., fish, fishery, fisherman, fishes, fishing, etc.) This allows you to automatically search variants of the search term without having to enter all of the keywords separately into the search box.

Stemming is turned on by default. If the search engine was able to perform stemming on your search, you will see the following message at the top of the search results page: "Your query has been expanded. Show Expansions". If you would like to turn off stemming:

  1. Click on the link to Show Expansions.
  2. In the Expansions box, click in the checkbox for "Stemming" to uncheck the box.
  3. In the lower right corner, click on the button to "Update Search". Your search will be re-run with stemming turned off.

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Search Expansions

Online Public Access also performs expansions on search queries. Search expansion is used to expand a user’s query to match additional results that may be applicable, such as matching search terms based on synonyms and fixing spelling errors.

Search expansion helps improve recall by matching similar terms and bringing back more results for the user. However, this may come at the price of reducing precision in the search. Therefore, search expansions are not turned on by default in OPA. If you are interested in expanding your search:

  1. Go to the top of the search page results page, to the message "Your query can be expanded. Show Expansions".
  2. Click on the link to Show Expansions.
  3. In the Expansions box, click any of the desired checkboxes to add the expanded term to your search.
  4. In the lower right corner, click on the button to "Update Search". Your search will be re-run with search expansions turned on.
  5. At any time you can go back and turn expansions off and re–run your search.

For example, a search on photograph allows you to expand and also search on architectural photographs, aerial photographs, photos, and pictures.

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Advanced Search

The Advanced Search page allows you to refine your search parameters. You can use each of the advanced search options alone (except for the Date search, which must be combined with at least one other search parameter), combine two or more from the same data source, or use them in combination with the search box at the top of the screen.

Please note that all of the advanced search options, except for Data Source and Search Request Timeout, only apply to Archival Descriptions or Authority Records. The advanced search options are grouped together on the screen to indicate whether they apply to Archival Descriptions only or Authority Records.

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The following options are available on the Advanced Search screen.


Data Source

This allows you to select one or more data sources in which to perform your search. The following Data Sources can be searched:

  • Online Public Access Sources – this is the default and searches all sources
  • Archival Descriptions – searches catalog records with no copy of the records available online
  • Archives.gov – searches web pages on Archives.gov
  • Authority Records – searches Organization and Person Name authority records
  • Archival Descriptions with Digital Objects – searches catalog records with a digital copy of the records available online

Click one or more checkboxes next to a Data Source to narrow your search. To search across all Data Sources, select the first checkbox next to "Online Public Access Sources".

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Person Name Only

The Person Name Only search allows you to search for specific People that are associated with archival descriptions. You can link from specific Person authority records to view archival descriptions associated with them.

To use this search, enter keywords in the Person Name Only search box, scroll down to the bottom of the screen and click Go. If you enter more than one search term, it will narrow your search. For example, if you enter adams john this will narrow the search more than if you just enter adams.

When you click on a Person Name on either the groupings page or expanded results page, the full description for that Person is displayed.

The full authority record for a person shows the total number of archival descriptions that the "preferred" person name appears in. That number is broken down by Roles. These roles reflect the association the person has with the described archival materials. The possible role types are Creator, Contributor, Donor, or Subject. Click on any of the links to view the related archival description(s).

Not all person names in our archival descriptions are indexed with person authority records. If you do not find the person you are looking for by using the Person Name Only search, try searching for the person name in the basic search box at the top of the page.

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Organization Name Only

The Organization Name Only search allows you to search for specific Organizations that are associated with archival descriptions. You can link from specific Organization authority records to view the archival descriptions associated with them.

To use this search, enter keywords in the Organization Name Only search box, scroll down to the bottom of the screen and click Go. You can also enter the acronym of an organization, such as FBI. However this can often obtain different results than if you search using the full name of the organization, such as Federal Bureau of Investigation.

When you click on an Organization on either the groupings page or expanded results page, the full description for that Organization is displayed.

The full authority record for an Organization shows the total number of archival descriptions that the preferred Organization Name(s) appear in. That number is broken down by Roles. These roles reflect the association the organization has with the described archival materials. The possible role types are Creator, Contributor, Donor, or Subject. Click on any of the links to view the related archival description(s).

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Date [Authority Records]

The Date search for authority records allows you to narrow your search by the dates associated with Organization or Person Name authority records. For Organizations these are the Establish and Abolish Dates, and for Person Names these are the Birth and Death Dates.

The Dates search for authority records consists of two date boxes in which you can enter a year (YYYY). OPA will find authority records with dates that fall between the provided date range.

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Date [Archival Descriptions]

The Dates search for archival descriptions allows you to narrow your search by the dates associated with the records. The following types of dates can be searched: Inclusive Dates, Coverage Dates, Production Date, Copyright Date, Broadcast Date or Release Date.

The Dates search for archival descriptions consists of two date boxes in which you can enter a year (YYYY). OPA will find descriptions of records that fall between the provided date range.

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Type of Archival Materials

The Type of Archival Materials search allows you to limit your search to archival descriptions that contain a particular type of records, such as Textual Records, Maps and Charts, or Moving Images.

All types are selected and searched by default. To select a single option simply click on an option in the selection box. To select more than one option, hold down the Ctrl key while clicking on all the desired options. To return to searching all types, hold down the Ctrl key and deselect any highlighted options.

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Level of Description

The Level of Description search allows you to limit your search to archival descriptions at a particular archival level such as Record Group, Collection, Series, File Unit, or Item.

All levels are selected and searched by default. To select a single option simply click on an option in the selection box. To select more than one option, hold down the Ctrl key while clicking on all the desired options. To return to searching all levels, hold down the Ctrl key and deselect any highlighted options.

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Location of Archival Materials

The Location of Archival Materials search allows you to limit your search to archival descriptions of materials held by a specific National Archives unit such as the Jimmy Carter Library.

All locations are selected and searched by default. To select a single option simply click on an option in the selection box. To select more than one option, hold down the Ctrl key while clicking on all the desired options. To return to searching all locations, hold down the Ctrl key and deselect any highlighted options.

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Title

The Title search allows you to enter keywords in the text box and limit your search on various title fields in archival description records. The following types of titles can be searched: Title, Other Title, Subtitle, Production Series Title, and Production Series Subtitle.

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Geographic References

The Geographic References search allows you to search for archival descriptions of materials that are associated with specific geographic locations. This searches on any Geographic References that have been added to archival descriptions as subject terms.

To use this search, enter keywords in the Geographic References search box, scroll down to the bottom of the screen and click Go. For example, you can enter a search for Belgium.

When you click on a result on either the groupings page or expanded results page, the full archival description is displayed. Scroll down to the section for Subjects Represented in the Archival Materials.

If you wish to see the full authority record for the Geographic Reference, click on the hyperlinked subject term in the archival description, e.g., Belgium (Europe) nation. The full authority record for a Geographic Reference shows the total number of archival descriptions that the term appears in.

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Record Group Number

The Record Group Number search allows you to search for archival descriptions belonging to a particular Record Group. It will search for the description of a particular Record Group, as well as any Series, File Units, and Items that fall under that Record Group.

To use this search, enter a Record Group Number in the search box (e.g., 330), scroll down to the bottom of the screen and click Go.

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Collection Identifier

The Collection Identifier search allows you to search for archival descriptions belonging to a particular Collection. It will search for the description of a particular Collection, as well as any Series, File Units, and Items that fall under that Collection.

To use this search, enter a Collection Identifier in the search box (e.g., JC–1033), scroll down to the bottom of the screen and click Go.

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Creator

The Creator search allows you to search for archival descriptions of records that are associated with a specific Creating Organization or Creating Individual (person).

To use this search, enter keywords in the Creator search box, scroll down to the bottom of the screen and click Go. For example, enter a search for Voice of America.

When you click on a result on either the groupings page or expanded results page, the full archival description is displayed. The Creator(s) field is displayed near the top of the full description.

If you wish to see the full authority record for the Organization Name or Person Name who created the records, click on the hyperlinked name after the Creator(s) label, e.g., U.S. Information Agency. Voice of America. (08/01/1953 — 04/01/1978).

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Description Identifier

The Description Identifier search allows you to narrow your search based on some of the most common identifiers used by the National Archives to identify archival descriptions. These identifiers include:

  • Record Group Number
  • Collection Identifier
  • National Archives Identifier
  • Local Identifier
  • Variant Control Number, such as a NAIL Control Number, Agency-Assigned Identifier, or HMS Entry Number
  • Former Record Group Number
  • Former Collection Identifier

Enter the appropriate number/identifier such as 194229 or "NWCTB–75–PI163E98" and click Go at the bottom of the screen.

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Relevancy Ranking

Relevancy ranking refers to how search results are ranked or ordered in the result set. The relevancy ranking is based on a variety of factors, including term frequency and what field the term was found in, as certain parts of a document — such as the Title field — may be more important than others.

OPA also allows us the ability to configure or modify the relevancy ranking based on our own parameters, allowing us to fine–tune the user experience.

For searches that are federated to another source (i.e. Archives.gov), OPA will present the results as they are returned from that source. OPA has no control over the relevancy ranking of federated search results.

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