Improve this page

Extended Statistics Aggregation

A multi-value metrics aggregation that computes extended statistics over numeric values extracted from the aggregated documents.

The _extended_stats aggregations is an extended version of the Statistics Aggregation, where additional metrics are added such as _sum_of_squares, _variance, _std_deviation and _std_deviation_bounds, these are detailed in their corresponding aggregation section:

• Variance Aggregation
• Standard Deviation Aggregation

Structuring

The following snippet captures the structure of extended statistics aggregations:

"<aggregation_name>": {
  "_extended_stats": {
    "_field": "<field_name>"
  },
  ...
}

Field

The <field_name> in the _field parameter defines the specific field from which the numeric values in the documents are extracted and used to compute the returned extended statistics.

Assuming the data consists of documents representing bank accounts, as shown in the sample dataset of Data Exploration section:

SEARCH /bank/
{
  "_query": "*",
  "_limit": 0,
  "_check_at_least": 1000,
  "_aggs": {
    "balance_stats": {
      "_extended_stats": {
        "_field": "balance"
      }
    }
  }
}

The above aggregation computes the balance statistics over all documents. The above will return the following:

  "aggregations": {
    "_doc_count": 1000,
    "balance_stats": {
      "_count": 1000,
      "_min": 7.99,
      "_max": 12699.46,
      "_avg": 2565.03304,
      "_sum": 2565033.04,
      "_sum_of_squares": 8844461934.66,
      "_variance": 2267334.7731415,
      "_std_deviation": 1505.7671709602053,
      "_std_deviation_bounds": {
        "_upper": 5576.56738192041,
        "_lower": -446.50130192041049
      }
    }
  }, ...

The name of the aggregation (balance_stats above) also serves as the key by which the aggregation result can be retrieved from the returned response.

Back

Next