BIASVAL

The BIASVAL field specifier (case sensitive) allows you to bias the score of result documents by a specified percentage, based on whether they include a specific value in the specified field.

NOTE: You can only use BIASVAL when the field is configured as:

Format

FieldText=BIASVAL{fieldValue,percentBoost}:fieldName
fieldValue The value that the specified field must contain to increase or decrease the weight by the percentBoost.
percentBoost

A percentage in the range -100 to 100. The percentage (positive or negative) by which to boost the relevance of documents that have the value fieldValue in the field fieldName. (The boosted relevance score cannot be greater than 100% or less than -100%.)

When you set AbsWeight to True, this is the absolute value by which to boost the weight and it is then not limited by +/- 100.
fieldName The name of the field that must be present (and must contain the proper value) for the document relevance to be boosted.

Example

FieldText=BIASVAL{Cambridge,10}:TOWN

A document whose TOWN field value is Cambridge has its weighting increased by 10% (although the weighting cannot go over 100%).

FieldText=BIASVAL{Cambridge,10}:TOWN+BIASVAL{London,-10}:TOWN

A document whose TOWN field value is Cambridge has its weighting increased by 10%, and a document whose TOWN field value is London has its weighting decreased by 10%. This example shows that biases can be negative as well as positive, and that you can include more than one set of parameters with the specifier.

See Also