Get records API

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Retrieves anomaly records for an anomaly detection job.

Request

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GET _ml/anomaly_detectors/<job_id>/results/records

Prerequisites

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Requires the monitor_ml cluster privilege. This privilege is included in the machine_learning_user built-in role.

Description

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Records contain the detailed analytical results. They describe the anomalous activity that has been identified in the input data based on the detector configuration.

There can be many anomaly records depending on the characteristics and size of the input data. In practice, there are often too many to be able to manually process them. The machine learning features therefore perform a sophisticated aggregation of the anomaly records into buckets.

The number of record results depends on the number of anomalies found in each bucket, which relates to the number of time series being modeled and the number of detectors.

Path parameters

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<job_id>
(Required, string) Identifier for the anomaly detection job.

Query parameters

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desc
(Optional, Boolean) If true, the results are sorted in descending order.
end
(Optional, string) Returns records with timestamps earlier than this time. Defaults to -1, which means it is unset and results are not limited to specific timestamps.
exclude_interim
(Optional, Boolean) If true, the output excludes interim results. Defaults to false, which means interim results are included.
from
(Optional, integer) Skips the specified number of records. Defaults to 0.
record_score
(Optional, double) Returns records with anomaly scores greater or equal than this value. Defaults to 0.0.
size
(Optional, integer) Specifies the maximum number of records to obtain. Defaults to 100.
sort
(Optional, string) Specifies the sort field for the requested records. By default, the records are sorted by the record_score value.
start
(Optional, string) Returns records with timestamps after this time. Defaults to -1, which means it is unset and results are not limited to specific timestamps.

Request body

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You can also specify the query parameters in the request body; the exception are from and size, use page instead:

page
Properties of page
from
(Optional, integer) Skips the specified number of records. Defaults to 0.
size
(Optional, integer) Specifies the maximum number of records to obtain. Defaults to 100.

Response body

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The API returns an array of record objects, which have the following properties:

actual
(array) The actual value for the bucket.
anomaly_score_explanation

(object) When present, it provides information about the factors impacting the initial anomaly score.

Properties of anomaly_score_explanation
anomaly_characteristics_impact
(Optional, integer) Impact from the duration and magnitude of the detected anomaly relative to the historical average.
anomaly_length
(Optional, integer) Length of the detected anomaly in the number of buckets.
anomaly_type
(Optional, string) Type of the detected anomaly: spike or dip.
high_variance_penalty
(Optional, boolean) Indicates reduction of anomaly score for the bucket with large confidence intervals. If a bucket has large confidence intervals, the score is reduced.
incomplete_bucket_penalty
(Optional, boolean) If the bucket contains fewer samples than expected, the score is reduced. If the bucket contains fewer samples than expected, the score is reduced.
lower_confidence_bound
(Optional, double) Lower bound of the 95% confidence interval.
multimodal_distribution
(Optional, boolean) Indicates whether the bucket values' probability distribution has several modes. When there are multiple modes, the typical value may not be the most likely.
multi_bucket_impact
(Optional, integer) Impact of the deviation between actual and typical values in the past 12 buckets.
single_bucket_impact
(Optional, integer) Impact of the deviation between actual and typical values in the current bucket.
typical_value
(Optional, double) Typical (expected) value for this bucket.
upper_confidence_bound
(Optional, double) Upper bound of the 95% confidence interval.
bucket_span
(number) The length of the bucket in seconds. This value matches the bucket_span that is specified in the job.
by_field_name
(string) The field used to split the data. In particular, this property is used for analyzing the splits with respect to their own history. It is used for finding unusual values in the context of the split.
by_field_value
(string) The value of by_field_name.
causes
(array) For population analysis, an over field must be specified in the detector. This property contains an array of anomaly records that are the causes for the anomaly that has been identified for the over field. If no over fields exist, this field is not present. This sub-resource contains the most anomalous records for the over_field_name. For scalability reasons, a maximum of the 10 most significant causes of the anomaly are returned. As part of the core analytical modeling, these low-level anomaly records are aggregated for their parent over field record. The causes resource contains similar elements to the record resource, namely actual, typical, geo_results.actual_point, geo_results.typical_point, *_field_name and *_field_value. Probability and scores are not applicable to causes.
detector_index
(number) A unique identifier for the detector.
field_name
(string) Certain functions require a field to operate on, for example, sum(). For those functions, this value is the name of the field to be analyzed.
function
(string) The function in which the anomaly occurs, as specified in the detector configuration. For example, max.
function_description
(string) The description of the function in which the anomaly occurs, as specified in the detector configuration.
geo_results

(optional, object) If the detector function is lat_long, this object contains comma delimited strings for the latitude and longitude of the actual and typical values.

Properties of geo_results
actual_point
(string) The actual value for the bucket formatted as a geo_point.
typical_point
(string) The typical value for the bucket formatted as a geo_point.
influencers
(array) If influencers was specified in the detector configuration, this array contains influencers that contributed to or were to blame for an anomaly.
initial_record_score
(number) A normalized score between 0-100, which is based on the probability of the anomalousness of this record. This is the initial value that was calculated at the time the bucket was processed.
is_interim
(Boolean) If true, this is an interim result. In other words, the results are calculated based on partial input data.
job_id
(string) Identifier for the anomaly detection job.
multi_bucket_impact
(number) An indication of how strongly an anomaly is multi bucket or single bucket. The value is on a scale of -5.0 to +5.0 where -5.0 means the anomaly is purely single bucket and +5.0 means the anomaly is purely multi bucket.
over_field_name
(string) The field used to split the data. In particular, this property is used for analyzing the splits with respect to the history of all splits. It is used for finding unusual values in the population of all splits. For more information, see Performing population analysis.
over_field_value
(string) The value of over_field_name.
partition_field_name
(string) The field used to segment the analysis. When you use this property, you have completely independent baselines for each value of this field.
partition_field_value
(string) The value of partition_field_name.
probability
(number) The probability of the individual anomaly occurring, in the range 0 to 1. For example, 0.0000772031. This value can be held to a high precision of over 300 decimal places, so the record_score is provided as a human-readable and friendly interpretation of this.
record_score
(number) A normalized score between 0-100, which is based on the probability of the anomalousness of this record. Unlike initial_record_score, this value will be updated by a re-normalization process as new data is analyzed.
result_type
(string) Internal. This is always set to record.
timestamp
(date) The start time of the bucket for which these results were calculated.
typical
(array) The typical value for the bucket, according to analytical modeling.

Additional record properties are added, depending on the fields being analyzed. For example, if it’s analyzing hostname as a by field, then a field hostname is added to the result document. This information enables you to filter the anomaly results more easily.

Examples

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GET _ml/anomaly_detectors/low_request_rate/results/records
{
  "sort": "record_score",
  "desc": true,
  "start": "1454944100000"
}
{
  "count" : 4,
  "records" : [
    {
      "job_id" : "low_request_rate",
      "result_type" : "record",
      "probability" : 1.3882308899968812E-4,
      "multi_bucket_impact" : -5.0,
      "record_score" : 94.98554565630553,
      "initial_record_score" : 94.98554565630553,
      "bucket_span" : 3600,
      "detector_index" : 0,
      "is_interim" : false,
      "timestamp" : 1577793600000,
      "function" : "low_count",
      "function_description" : "count",
      "typical" : [
        28.254208230188834
      ],
      "actual" : [
        0.0
      ]
    },
  ...
  ]
}