Events

Use event detection to analyze text documents for specific types of events and their related entities. Amazon Comprehend supports event detection across large collections of documents using asynchronous analysis jobs. For more information about events, including example event analysis jobs, see Announcing the launch of Amazon Comprehend Events

Entities

From the input text, Amazon Comprehend extracts a list of entities that are related to the detected event. An entity can be a real-world object, such as a person, place, or location; an entity can also be a concept, such as a measurement, date, or quantity. Each occurrence of an entity is identified by a mention, which is a textual reference to the entity in the input text. For each unique entity, all mentions are grouped into a list. This list provides details for each location in the input text where the entity occurs. Amazon Comprehend detects only the entities associated with supported event types.

Each entity associated with a supported event type returns with the following related details:

• Mentions: Details for each occurrence of the same entity in the input text.

  • BeginOffset: A character offset in the input text that shows where the mention begins (the first character is at position 0).

  • EndOffset: A character offset in the input text that shows where the mention ends.

  • Score: The level of confidence that Amazon Comprehend has in the accuracy of the entity's type.

  • GroupScore: The level of confidence from Amazon Comprehend that the mention is correctly grouped with other mentions of the same entity.

  • Text: The text of the entity.

  • Type: The entity's type. For all supported entity types, see Entity types.

Events

Amazon Comprehend returns the list of events (of supported event types) that it detects in the input text. Each event returns with the following related details:

• Type: The event's type. For all supported event types, see Event types.

• Arguments: A list of arguments that are related to the detected event. An argument consists of an entity that is related to the detected event. The argument's role describes the relationship, such as who did what, where and when.

  • EntityIndex: An index value that identifies an entity from the list of entities that Amazon Comprehend returned for this analysis.

  • Role: The argument type, which describes how the entity for this argument is related to the event. For all supported argument types, see Argument types.

  • Score: The level of confidence that Amazon Comprehend has in the accuracy of the role detection.

• Triggers: A list of triggers for the detected event. A trigger is a single word or phrase that indicates the occurrence of the event.

  • BeginOffset: A character offset in the input text that shows where the trigger begins (the first character is at position 0).

  • EndOffset: A character offset in the input text that shows where the trigger ends.

  • Score: The level of confidence that Amazon Comprehend has in the accuracy of the detection.

  • Text: The text of the trigger.

  • GroupScore: The level of confidence from Amazon Comprehend that the trigger is correctly grouped with other triggers for the same event.

  • Type: The type of event that this trigger indicates.

Detect events results format

When your event detection job completes, Amazon Comprehend writes the analysis results to the Amazon S3 output location that you specified when you started the job.

For each detected event, the output provides details in the following format:

{
   "Entities": [
     {
       "Mentions": [
         {
           "BeginOffset": number,
           "EndOffset": number,
           "Score": number,
           "GroupScore": number,
           "Text": "string",
           "Type": "string"
         }, ...
       ]    
     }, ...
   ],
   "Events": [
     {
       "Type": "string",
       "Arguments": [
         {                   
           "EntityIndex": number,   
           "Role": "string",
           "Score": number
         }, ...
       ],
       "Triggers": [
         {
           "BeginOffset": number,
           "EndOffset": number,
           "Score": number,
           "Text": "string",
           "GroupScore": number,
           "Type": "string"
         }, ...
       ]
     }, ...
   ]
 }

Supported types for entities, events, and arguments

Entity types

Type	Description
DATE	Any reference to a date or time, whether specific or general.
FACILITY	Buildings, airports, highways, bridges, and other permanent man-made structures and real estate improvements.
LOCATION	Physical locations such as streets, cities, states, countries, bodies of water, or geographic coordinates.
MONETARY_VALUE	The value of something in US or other currency. The value can be specific or approximate.
ORGANIZATION	Companies and other groups of people defined by an established organizational structure.
PERSON	The names or nicknames of individuals or fictional characters.
PERSON_TITLE	Any title which describes a person, which is usually an employment category (such as CEO) or honorific (such as Mr.).
QUANTITY	A number or value and the unit of measurement.
STOCK_CODE	A stock ticker symbol, such as AMZN, an International Securities Identification Number (ISIN), Committee on Uniform Securities Identification Procedures (CUSIP), or Stock Exchange Daily Official List (SEDOL).

Event types

Type	Description
BANKRUPTCY	A legal proceeding involving a person or company unable to repay outstanding debts.
EMPLOYMENT	Occurs when an employee is hired, fired, retired, or otherwise changes employment state.
CORPORATE_ACQUISTION	Occurs when a company obtains the possession of most or all of another company's shares or physical assets to gain control of that company.
INVESTMENT_GENERAL	Occurs when a person or company purchases an asset with the prospect of generating future income or appreciation.
CORPORATE_MERGER	Occurs when two or more companies unite to create a new legal entity.
IPO	An initial public offering (IPO) of shares of a private corporation to the public in a new stock issuance.
RIGHTS_ISSUE	A group of rights offered to existing shareholders to purchase additional stock shares, known as subscription warrants, in proportion to their existing holdings.
SECONDARY_OFFERING	An offer of securities by a shareholder of a company.
SHELF_OFFERING	A Securities and Exchange Commission (SEC) provision that allows an issuer to register a new issue of security and sell portions of the issue over a period of time without re-registering the security or incurring penalties. Also known as a shelf registration.
TENDER_OFFERING	An offer to purchase some or all of shareholders' shares in a company.
STOCK_SPLIT	Occurs when a company's board of directors increases the number of shares that are outstanding by issuing more shares to current shareholders. This event also applies to reverse stock splits.

Argument types

Argument types for BANKRUPTCY
Argument type	Description
FILER	The person or company filing the bankruptcy.
DATE	The date or time of bankruptcy.
PLACE	Location or facility where (or nearest to where) the bankruptcy took place.

Argument types for EMPLOYMENT
Type	Description
EMPLOYEE	The person employed by a company.
EMPLOYEE_TITLE	The title of the employee.
EMPLOYER	The person or company employing the employee.
START_DATE	The start date or time of the employment.
END_DATE	The end date or time of the employment.

Argument types for CORPORATE_ACQUISTION, INVESTMENT_GENERAL
Type	Description
AMOUNT	The monetary value associated with the transaction.
INVESTEE	The person or company associated with the investment.
INVESTOR	The person or company investing in the asset.
DATE	The date or time of the acquisition or investment.
PLACE	Location where (or nearest to where) the acquisition or investment took place.

Argument types for CORPORATE_MERGER
Type	Description
DATE	The date or time of the merger.
NEW_COMPANY	The new legal entity resulting from the merger.
PARTICIPANT	The company involved in the merger.

Argument types for IPO, RIGHTS_ISSUE, SECONDARY_OFFERING, SHELF_OFFERING, TENDER_OFFERING
Type	Description
EXPIRE_DATE	The expiration date or time of the offering.
INVESTOR	The person or company investing in the asset.
OFFEREE	The person or company receiving the offering.
OFFERING_AMOUNT	The monetary value associated with the offering.
OFFERING_DATE	The date or time of the offering.
OFFEROR	The person or company initiating the offering.
OFFEROR_TOTAL_VALUE	The total monetary value associated with the offering.
RECORD_DATE	The record date or time of the offering.
SELLING_AGENT	The person or company facilitating the sale of the offering.
SHARE_PRICE	The monetary value associated with the share price.
SHARE_QUANTITY	The number of shares associated with the offering.
UNDERWRITERS	The company associated with the underwriting of the offering.

Argument types for STOCK_SPLIT
Type	Description
COMPANY	The company issuing shares of the stock split.
DATE	The date or time of the stock split.
SPLIT_RATIO	The ratio of the increased new number of shares outstanding to the current number of shares before the stock split.