OpenSearch/docs/en/rest-api/ml/resultsresource.asciidoc

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//lcawley Verified example output 2017-04-11
[[ml-results-resource]]
==== Results Resources
Different results types are created for each job.
Anomaly results for _buckets_, _influencers_ and _records_ can be queried using the results API.
These results are written for every `bucket_span`, with the timestamp being the start of the time interval.
As part of the results, scores are calculated for each anomaly result type and each bucket interval.
These are aggregated in order to reduce noise, and normalized in order to identify and rank the most mathematically significant anomalies.
Bucket results provide the top level, overall view of the job and are ideal for alerting on.
For example, at 16:05 the system was unusual.
This is a summary of all the anomalies, pinpointing when they occurred.
Influencer results show which entities were anomalous and when.
For example, at 16:05 `user_name: Bob` was unusual.
This is a summary of all anomalies for each entity, so there can be a lot of these results.
Once you have identified a notable bucket time, you can look to see which entites were significant.
Record results provide the detail showing what the individual anomaly was, when it occurred and which entity was involved.
For example, at 16:05 Bob sent 837262434 bytes, when the typical value was 1067 bytes.
Once you have identified a bucket time and/or a significant entity, you can drill through to the record results
in order to investigate the anomalous behavior.
//TBD Add links to categorization
Categorization results contain the definitions of _categories_ that have been identified.
These are only applicable for jobs that are configured to analyze unstructured log data using categorization.
These results do not contain a timestamp or any calculated scores.
* <<ml-results-buckets,Buckets>>
* <<ml-results-influencers,Influencers>>
* <<ml-results-records,Records>>
* <<ml-results-categories,Categories>>
[float]
[[ml-results-buckets]]
===== Buckets
Bucket results provide the top level, overall view of the job and are best for alerting.
Each bucket has an `anomaly_score`, which is a statistically aggregated and
normalized view of the combined anomalousness of all record results within each bucket.
One bucket result is written for each `bucket_span` for each job, even if it is not considered to be anomalous
(when it will have an `anomaly_score` of zero).
Upon identifying an anomalous bucket, you can investigate further by either
expanding the bucket resource to show the records as nested objects or by
accessing the records resource directly and filtering upon date range.
A bucket resource has the following properties:
`anomaly_score`::
(number) The maximum anomaly score, between 0-100, for any of the bucket influencers.
This is an overall, rate limited score for the job.
All the anomaly records in the bucket contribute to this score.
This value may be updated as new data is analyzed.
`bucket_influencers[]`::
(array) An array of bucket influencer objects.
For more information, see <<ml-results-bucket-influencers,Bucket Influencers>>.
`bucket_span`::
(time units) The length of the bucket.
This value matches the `bucket_span` that is specified in the job.
`event_count`::
(number) The number of input data records processed in this bucket.
`initial_anomaly_score`::
(number) The maximum `anomaly_score` for any of the bucket influencers.
This is this initial value calculated at the time the bucket was processed.
`is_interim`::
(boolean) If true, then this bucket result is an interim result.
In other words, it is calculated based on partial input data.
`job_id`::
(string) The unique identifier for the job that these results belong to.
`processing_time_ms`::
(number) The time in milliseconds taken to analyze the bucket contents and calculate results.
`record_count`::
(number) The number of anomaly records in this bucket.
`result_type`::
(string) Internal. This value is always set to "bucket".
`timestamp`::
(date) The start time of the bucket. This timestamp uniquely identifies the bucket. +
NOTE: Events that occur exactly at the timestamp of the bucket are included in
the results for the bucket.
[float]
[[ml-results-bucket-influencers]]
===== Bucket Influencers
Bucket influencer results are available as nested objects contained within bucket results.
These results are an aggregation for each the type of influencer.
For example if both client_ip and user_name were specified as influencers,
then you would be able to find when client_ip's or user_name's were collectively anomalous.
There is a built-in bucket influencer called `bucket_time` which is always available.
This is the aggregation of all records in the bucket, and is not just limited to a type of influencer.
NOTE: A bucket influencer is a type of influencer. For example, `client_ip` or `user_name`
can be bucket influencers, whereas `192.168.88.2` and `Bob` are influencers.
An bucket influencer object has the following properties:
`anomaly_score`::
(number) A normalized score between 0-100, calculated for each bucket influencer.
This score may be updated as newer data is analyzed.
`bucket_span`::
(time units) The length of the bucket.
This value matches the `bucket_span` that is specified in the job.
`initial_anomaly_score`::
(number) The score between 0-100 for each bucket influencers.
This is this initial value calculated at the time the bucket was processed.
`influencer_field_name`::
(string) The field name of the influencer. For example `client_ip` or `user_name`.
`influencer_field_value`::
(string) The field value of the influencer. For example `192.168.88.2` or `Bob`.
`is_interim`::
(boolean) If true, then this is an interim result.
In other words, it is calculated based on partial input data.
`job_id`::
(string) The unique identifier for the job that these results belong to.
`probability`::
(number) The probability that the bucket has this behavior, in the range 0 to 1. For example, 0.0000109783.
This value can be held to a high precision of over 300 decimal places, so the `anomaly_score` is provided as a
human-readable and friendly interpretation of this.
`raw_anomaly_score`::
(number) Internal.
`result_type`::
(string) Internal. This value is always set to "bucket_influencer".
`sequence_num`::
(number) Internal.
`timestamp`::
(date) This value is the start time of the bucket for which these results have been calculated for.
[float]
[[ml-results-influencers]]
===== Influencers
Influencers are the entities that have contributed to, or are to blame for, the anomalies.
Influencer results will only be available if an `influencer_field_name` has been specified in the job configuration.
Influencers are given an `influencer_score`, which is calculated
based on the anomalies that have occurred in each bucket interval.
For jobs with more than one detector, this gives a powerful view of the most anomalous entities.
For example, if analyzing unusual bytes sent and unusual domains visited, if user_name was
specified as the influencer, then an 'influencer_score' for each anomalous user_name would be written per bucket.
E.g. If `user_name: Bob` had an `influencer_score` > 75,
then `Bob` would be considered very anomalous during this time interval in either or both of those attack vectors.
One `influencer` result is written per bucket for each influencer that is considered anomalous.
Upon identifying an influencer with a high score, you can investigate further
by accessing the records resource for that bucket and enumerating the anomaly
records that contain this influencer.
An influencer object has the following properties:
`bucket_span`::
(time units) The length of the bucket.
This value matches the `bucket_span` that is specified in the job.
`influencer_score`::
(number) A normalized score between 0-100, based on the probability of the influencer in this bucket,
aggregated across detectors.
Unlike `initial_influencer_score`, this value will be updated by a re-normalization process as new data is analyzed.
`initial_influencer_score`::
(number) A normalized score between 0-100, based on the probability of the influencer, aggregated across detectors.
This is this initial value calculated at the time the bucket was processed.
`influencer_field_name`::
(string) The field name of the influencer.
`influencer_field_value`::
(string) The entity that influenced, contributed to, or was to blame for the
anomaly.
`is_interim`::
(boolean) If true, then this is an interim result.
In other words, it is calculated based on partial input data.
`job_id`::
(string) The unique identifier for the job that these results belong to.
`probability`::
(number) The probability that the influencer has this behavior, in the range 0 to 1.
For example, 0.0000109783.
This value can be held to a high precision of over 300 decimal places,
so the `influencer_score` is provided as a human-readable and friendly interpretation of this.
// For example, 0.03 means 3%. This value is held to a high precision of over
//300 decimal places. In scientific notation, a value of 3.24E-300 is highly
//unlikely and therefore highly anomalous.
`result_type`::
(string) Internal. This value is always set to "influencer".
`sequence_num`::
(number) Internal.
`timestamp`::
(date) The start time of the bucket for which these results have been calculated for.
NOTE: Additional influencer properties are added, depending on the fields being analyzed.
For example, if analysing `user_name` as an influencer, then a field `user_name` would be added to the
result document. This allows easier filtering of the anomaly results.
[float]
[[ml-results-records]]
===== Records
Records contain the detailed analytical results. They describe the anomalous activity that
has been identified in the input data based upon the detector configuration.
For example, if you are looking for unusually large data transfers,
an anomaly record would identify the source IP address, the destination,
the time window during which it occurred, the expected and actual size of the
transfer and the probability of this occurring.
There can be many anomaly records depending upon the characteristics and size
of the input data; in practice too many to be able to manually process.
The {xpack} {ml} 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 timeseries being modelled and the number of detectors.
A record object has the following properties:
`actual`::
(array) The actual value for the bucket.
`bucket_span`::
(time units) The length of the bucket.
This value matches the `bucket_span` that is specified in the job.
`by_field_name`::
(string) The name of the analyzed field. Only present if specified in the detector.
For example, `client_ip`.
`by_field_value`::
(string) The value of `by_field_name`. Only present if specified in the detector.
For example, `192.168.66.2`.
`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 will not be 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 will be 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`, `*_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. E.g. `sum()`.
For those functions, this 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.
`influencers`::
(array) If `influencers` was specified in the detector configuration, then
this array contains influencers that contributed to or were to blame for an anomaly.
`initial_record_score`::
(number) A normalized score between 0-100, based on the probability of the anomalousness of this record.
This is this initial value calculated at the time the bucket was processed.
`is_interim`::
(boolean) If true, then this anomaly record is an interim result.
In other words, it is calculated based on partial input data
`job_id`::
(string) The unique identifier for the job that these results belong to.
`over_field_name`::
(string) The name of the over field that was used in the analysis. Only present if specified in the detector.
Over fields are used in population analysis.
For example, `user`.
`over_field_value`::
(string) The value of `over_field_name`. Only present if specified in the detector.
For example, `Bob`.
`partition_field_name`::
(string) The name of the partition field that was used in the analysis. Only present if specified in the detector.
For example, `region`.
`partition_field_value`::
(string) The value of `partition_field_name`. Only present if specified in the detector.
For example, `us-east-1`.
`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.
//In scientific notation, a value of 3.24E-300 is highly unlikely and therefore
//highly anomalous.
`record_score`::
(number) A normalized score between 0-100, 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".
`sequence_num`::
(number) Internal.
`timestamp`::
(date) The start time of the bucket for which these results have been calculated for.
`typical`::
(array) The typical value for the bucket, according to analytical modeling.
NOTE: Additional record properties are added, depending on the fields being analyzed.
For example, if analyzing `hostname` as a _by field_, then a field `hostname` would be added to the
result document. This allows easier filtering of the anomaly results.
[float]
[[ml-results-categories]]
===== Categories
When `categorization_field_name` is specified in the job configuration,
it is possible to view the definitions of the resulting categories.
A category definition describes the common terms matched and contains examples of matched values.
The anomaly results from a categorization analysis are available as _buckets_, _influencers_ and _records_ results.
For example, at 16:45 there was an unusual count of log message category 11.
These definitions can be used to describe and show examples of `categorid_id: 11`.
A category resource has the following properties:
`category_id`::
(unsigned integer) A unique identifier for the category.
`examples`::
(array) A list of examples of actual values that matched the category.
`job_id`::
(string) The unique identifier for the job that these results belong to.
`max_matching_length`::
(unsigned integer) The maximum length of the fields that matched the category.
The value is increased by 10% to enable matching for similar fields that have not been analyzed.
`regex`::
(string) A regular expression that is used to search for values that match the category.
`terms`::
(string) A space separated list of the common tokens that are matched in values of the category.