Triple

T10082148
Position Surface form Disambiguated ID Type / Status
Subject Red Line Alewife branch E213926 entity
Predicate usesRollingStock P5426 FINISHED
Object MBTA Red Line subway cars
MBTA Red Line subway cars are the electric rapid transit vehicles that operate on Boston’s Red Line, providing high-capacity urban rail service across key corridors including the Alewife branch.
E840553 NE FINISHED

How this triple was built (4 steps)

Every LLM step that produced this triple, in pipeline order — named-entity classification, the disambiguation choices (the exact options shown, with the pick highlighted), and the generated description. The batch + timestamp of each is in the Provenance table below.

NER Named-entity recognition gpt-5-mini
Instruction
Given a phrase, classify it is english named entity (e.g., persons, organizations, works of art) in Latin script, or not (e.g., literals, dates, URLs, verbose phrases). For disambiguation, the statement where the phrase occurs as object is also given. Please return a JSON object with `phrase` (string, the phrase being analyzed) and `is_ne` (boolean, indicating whether the phrase is a Named Entity).
Input
Phrase: MBTA Red Line subway cars | Statement: [Red Line Alewife branch, usesRollingStock, MBTA Red Line subway cars]
NED1 Entity disambiguation (via context triple) gpt-5-mini-2025-08-07
Target entity: MBTA Red Line subway cars
Context triple: [Red Line Alewife branch, usesRollingStock, MBTA Red Line subway cars]
  • A. MBTA Red Line 1500/1600 series cars
    The MBTA Red Line 1500/1600 series cars are an older generation of heavy-rail subway vehicles that have long served Boston’s Red Line, particularly known for their stainless-steel bodies and traditional rapid-transit design.
  • B. MBTA Red Line 1700 series cars
    The MBTA Red Line 1700 series cars are a fleet of heavy-rail subway vehicles used on Boston’s Red Line, particularly associated with service on the Braintree Branch.
  • C. MBTA Red Line 1800 series cars
    The MBTA Red Line 1800 series cars are a fleet of heavy-rail subway vehicles used on Boston’s Red Line, featuring stainless-steel bodies and modernized interiors compared to earlier generations of MBTA rolling stock.
  • D. MBTA Green Line rolling stock
    MBTA Green Line rolling stock comprises the light rail vehicles used on Boston’s Green Line, including multiple generations of trolleys that serve as the backbone of the city’s surface and subway light rail service.
  • E. MBTA Commuter Rail coaches
    MBTA Commuter Rail coaches are bi-level and single-level passenger railcars used by the Massachusetts Bay Transportation Authority to provide regional rail service across Greater Boston and surrounding areas.
  • F. None of above. chosen
  • G. Unsure - the case is ambiguous/there is not enough information to decide.
NEDg Description generation gpt-5.1
Instruction
Generate a one-sentence description of the target entity. 
You are given a context triple in the form (subject, predicate, object), where the object is the target entity. 
# Instructions
Use the triple to infer relevant information about the entity. Describe the entity based on what is most defining, well-known. 
Avoid repeating the information from the triple, unless really essential.
# Response Format
Return only the sentence: "Description: [one-sentence description of the target entity]"
Input
Entity: MBTA Red Line subway cars
Triple: [Red Line Alewife branch, usesRollingStock, MBTA Red Line subway cars]
Generated description
MBTA Red Line subway cars are the electric rapid transit vehicles that operate on Boston’s Red Line, providing high-capacity urban rail service across key corridors including the Alewife branch.
NED2 Entity disambiguation (via description) gpt-5-mini-2025-08-07
Target entity: MBTA Red Line subway cars
Target entity description: MBTA Red Line subway cars are the electric rapid transit vehicles that operate on Boston’s Red Line, providing high-capacity urban rail service across key corridors including the Alewife branch.
  • A. MBTA Red Line 1500/1600 series cars
    The MBTA Red Line 1500/1600 series cars are an older generation of heavy-rail subway vehicles that have long served Boston’s Red Line, particularly known for their stainless-steel bodies and traditional rapid-transit design.
  • B. MBTA Red Line 1700 series cars
    The MBTA Red Line 1700 series cars are a fleet of heavy-rail subway vehicles used on Boston’s Red Line, particularly associated with service on the Braintree Branch.
  • C. MBTA Red Line 1800 series cars
    The MBTA Red Line 1800 series cars are a fleet of heavy-rail subway vehicles used on Boston’s Red Line, featuring stainless-steel bodies and modernized interiors compared to earlier generations of MBTA rolling stock.
  • D. MBTA Green Line rolling stock
    MBTA Green Line rolling stock comprises the light rail vehicles used on Boston’s Green Line, including multiple generations of trolleys that serve as the backbone of the city’s surface and subway light rail service.
  • E. MBTA Commuter Rail coaches
    MBTA Commuter Rail coaches are bi-level and single-level passenger railcars used by the Massachusetts Bay Transportation Authority to provide regional rail service across Greater Boston and surrounding areas.
  • F. None of above. chosen

Provenance (5 batches)

The batch behind each pipeline step, in order, with when it ran. Timestamps are batch-level — stages were processed in waves, so the object chain (NER → NED1 → NEDg → NED2) reads in order, but predicate / elicitation batches can sit in a different wave.

Step Stage Batch ID Status When
creating Elicitation batch_69ca839bf730819086900c323c9b8c95 completed March 30, 2026, 2:07 p.m.
NER Named-entity recognition batch_69cdd03482d481908b03d35dc2d16395 completed April 2, 2026, 2:11 a.m.
NED1 Entity disambiguation (via context triple) batch_69d2b66b256c8190861066f7c19008d2 completed April 5, 2026, 7:22 p.m.
NEDg Description generation batch_69d2b78f3c248190b104937e2d669882 completed April 5, 2026, 7:27 p.m.
NED2 Entity disambiguation (via description) batch_69d2b84a26a481908ab2705d5883cfce completed April 5, 2026, 7:30 p.m.
Created at: March 30, 2026, 9 p.m.