BIAS

The BIAS field specifier (case sensitive) allows you to bias the score of results at query time according to the numerical proximity of the specified field to a given value.

Format

FieldText=BIAS{optimum,range,percentage}:yourFields

optimum	The value that yourFields must contain to increase or decrease the weight by the maximum percentage.
range	A positive number that determines the range of the specified optimum value. If the specified field contains a value that is in the range of (optimum - range) to (optimum + range), the weight is increased or decreased according to the specified percentage.
percentage	A percentage in the range 100 to -100. If the value of the specified field is within the specified range, the score of the result is increased or decreased according to how close the value is to the specified optimum. NOTE: When AbsWeight is set to true, this is the absolute value by which to boost the weight and it is then not limited by +/- 100.
yourFields	One or more fields. A document has its score boosted if it contains one of these fields, and if this field contains a number within the specified range of the optimum value. Separate multiple fields with colons (:). There must be no space before or after a colon.

Example

FieldText=BIAS{100,50,10}:*/PRICE

A document whose PRICE field value is within the range 50 either side of 100 has its weight increased on a linear scale from 10% if the price is 100, to 0% if the price is 50 or 150.

FieldText=BIAS{100,50,-10}:*/PRICE

A document whose PRICE field value is within the range 50 either side of 100 has its weight decreased on a linear scale from -10% if the price is 100, to -0% if the price is 50 or 150.

FieldText=BIAS{1103918400,259200,25}:autn_date

A document whose autn_date field value is within the range 259200 either side of 1103918400 has its weight increased on a linear scale from 25% if the price is 1103918400, to 0%, if the date is 1103659200 or 1104177600.