Document ranking signal used to adjust relevance scoring. Signals apply only when results are ordered by relevance, so an explicit sort overrides them. Targeting an unknown field returns search:field_unknown; targeting a field without sorting enabled returns search:usage_unsupported; a signal function unsupported by the field type returns search:matcher:type_unsupported. See Signals.
Example
{
"field": "purchases",
"saturation": {
"pivot": 50
},
"weight": 0.5
}
Properties
fieldstringrequired
Field to read the value from, as named in the index definition. Must be a numeric or timestamp field with sorting enabled.
Example
"purchases"
saturationSaturation
Ranks by how far the value rises above a pivot. For number fields.
Example
{
"pivot": 50
}
1 property
pivotnumberrequired
The value that counts for half of what the signal can give. Must be above zero.
Format
double
Example
50
decayDecay
Ranks by how long ago the value was. For timestamp fields.
Example
{
"halfLife": 604800
}
1 property
halfLifeintegerrequired
How many seconds it takes for the signal to be worth half as much. Must be above zero.
Format
int64
Example
604800
linearLinear
Ranks by how far the value is toward a ceiling, as value / ceiling held between 0 and 1. For number fields holding a score computed elsewhere.
Example
{
"ceiling": 1
}
1 property
ceilingnumberrequired
The value that counts for all of what the signal can give. Must be above zero.
Format
double
Example
1
weightnumber
How much the signal can lift a document at most, as a share of its score.
Default
1
Format
float
Endpoints
Endpoints where the request or responses uses this type.