Generic

Word count
Sometimes it can be useful to get the word length of a field, especially for models designed to personalize different types of content. You can use the word_count feature extractor to get the length of a string field with the following config:
- name: title_length
  type: word_count
  scope: item
  field: item.title // must be a string
Relative number
More advanced feature type, which can scale numerical feature using different methods. Example config for a static scaling with predefined min and max values and log transformation:
- name: price
  type: relative_number
  method:
    type: minmax
    min: 0
    max: 100   
  field: price
  source: item
  scope: item
Supported methods:
minmax: uses min and max fields to scale
log_minmax: uses min and max fields to scale, but the value is log-transformed before.
estimate_minmax: using a sample of latest pool_size events (sampled with sample_rate rate), estimate min and max values used for scaling
estimate_histogram: using a sample of latest pool_size events (sampled with sample_rate rate), use a histogram scaling over bucket_count buckets. So for a price field from the example above, histogram scaling will translate absolute value into a percentile over a sampled pool of values.
Estimate methods are useful for rough scaling of values, when you cannot easily define min and max:
estimate_minmax should be used when the value can be linearly scaled, and there are no outliers
estimate_histogram can handle skewed distributions and outliers, but has quantized output: there is only bucket_count possible output values.
Example config for an estimate_histogram:
- name: price
  type: relative_number
  method:
    type: estimate_histogram
    pool_size: 100 // for a pool size of 100
    sample_rate: 10 // we sample every 10th event in the pool 
    bucket_count: 5 // so value will be mapped to 0-20-40-60-80-100 percentiles
  field: price
  source: item
  scope: item
List size
Counts the number of items in a string or numerical list. Example:
- name: toggled_filters_count
  type: list_size
  field: filters
  source: item
Date and Time
Relevancy
Last modified 5mo ago