Google Search Appliance Creating the Search Experience - Manual (Page 69)

Google Search Appliance: Creating the Search Experience Best Practices 69
Using Result Biasing to Influence Result Ranking
The Google Search Appliance ranks the documents that it finds in response to a user search query.
For each document, the search appliance calculates a score that:
• Reflects the probable relevance of the document content
• Determines the order in which results appear on the search results page
You can use result biasing to increase or decrease the scores of specified sources, or types of sources, in
the search index. These local settings may affect the order of the search results. You can influence
results ranking by using:
• Source biasing—enables you to affect scores of documents that belong to a specified collection,
match certain URL patterns., or are fed from a data source. See “Using Source Biasing” on page 70.
• Date biasing—enables you to affect scores of documents by date. See “Using Date Biasing” on
page 70.
• Metadata and entity biasing—enables you to affect scores of documents based on metadata or
entities associated with documents. See “Using Metadata and Entity Biasing” on page 71.
Result biasing is one way to affect the order of results. You might consider using other features to meet
the following objectives:
• To ensure that a particular document appears at the top of the results, consider using a key match.
For more information about this topic, refer to “Using KeyMatches to Guide Users to URLs” on
page 41.
• To allow users to search only a certain set of documents, consider using a collection. For more
information about this topic, see “Using Collections with Front Ends” on page 14.
Working with Result Biasing
To influence search appliance rankings, use a result biasing policy. A result biasing policy determines the
source biasing, date biasing, and metadata and entity biasing settings that are used with a front end. A
default result biasing policy (default_policy) is built into the search appliance. You can use default_policy,
or create one or more custom result biasing policies. A result biasing policy is specific to a front end, so
it can be aimed at specific types of end users.
To work with result biasing:
1. Create a result biasing policy using the Serving > Result Biasing page in the Admin Console.
2. Configure source biasing, date biasing, or metadata and entity biasing for the policy using the
Serving > Result Biasing > Edit page in the Admin Console. A menu-driven interface allows weak
or strong increases or decreases, and requires no complex coding or scripting. You can use 11
settings to adjust result biasing from least influence to most influence.
3. Enable the result biasing policy by selecting it for use with a front end using the Serving > Filters
page in the Admin Console.
If you are updating a search appliance with existing result biasing settings, your existing settings and any
existing front ends that have result biasing turned on remain intact after the update.
For complete information about using the Serving > Result Biasing page, the Serving > Result Biasing
> Edit page and the Serving > Filters page, refer to the Help Center in the Admin Console.