Triple

T3404407
Position Surface form Disambiguated ID Type / Status
Subject MBTA Braintree Branch E71735 entity
Predicate usesRollingStock P5426 FINISHED
Object 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.
E355214 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 1500/1600 series cars | Statement: [MBTA Braintree Branch, usesRollingStock, MBTA Red Line 1500/1600 series cars]
NED1 Entity disambiguation (via context triple) gpt-5-mini-2025-08-07
Target entity: MBTA Red Line 1500/1600 series cars
Context triple: [MBTA Braintree Branch, usesRollingStock, MBTA Red Line 1500/1600 series cars]
  • A. MBTA Type 7 Light Rail Vehicle
    The MBTA Type 7 Light Rail Vehicle is a high-floor, articulated streetcar used on Boston’s Green Line, known for its distinctive design and role as one of the system’s primary light rail fleets.
  • B. MBTA Type 8 Light Rail Vehicle
    The MBTA Type 8 Light Rail Vehicle is a low-floor, articulated streetcar used on Boston’s Green Line, designed to improve accessibility and passenger capacity on the system’s light rail routes.
  • C. 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.
  • D. MBTA Type 9 Light Rail Vehicle
    The MBTA Type 9 Light Rail Vehicle is a modern, low-floor streetcar used on Boston’s Green Line that features improved accessibility, passenger comfort, and energy efficiency compared to earlier MBTA light rail fleets.
  • 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 1500/1600 series cars
Triple: [MBTA Braintree Branch, usesRollingStock, MBTA Red Line 1500/1600 series cars]
Generated description
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.
NED2 Entity disambiguation (via description) gpt-5-mini-2025-08-07
Target entity: MBTA Red Line 1500/1600 series cars
Target entity description: 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.
  • A. MBTA Type 7 Light Rail Vehicle
    The MBTA Type 7 Light Rail Vehicle is a high-floor, articulated streetcar used on Boston’s Green Line, known for its distinctive design and role as one of the system’s primary light rail fleets.
  • B. MBTA Type 8 Light Rail Vehicle
    The MBTA Type 8 Light Rail Vehicle is a low-floor, articulated streetcar used on Boston’s Green Line, designed to improve accessibility and passenger capacity on the system’s light rail routes.
  • C. 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.
  • D. MBTA Type 9 Light Rail Vehicle
    The MBTA Type 9 Light Rail Vehicle is a modern, low-floor streetcar used on Boston’s Green Line that features improved accessibility, passenger comfort, and energy efficiency compared to earlier MBTA light rail fleets.
  • 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_69ad85aac4808190a092c9cc8911f584 completed March 8, 2026, 2:20 p.m.
NER Named-entity recognition batch_69adb8e8ea848190b4ac167f1aba8ebd completed March 8, 2026, 5:59 p.m.
NED1 Entity disambiguation (via context triple) batch_69b34bd69f388190981da6454dfd4fb1 completed March 12, 2026, 11:27 p.m.
NEDg Description generation batch_69b34e486c3c81908e73c5b75baf119c completed March 12, 2026, 11:37 p.m.
NED2 Entity disambiguation (via description) batch_69b34fc420b08190baee678721b1b32c completed March 12, 2026, 11:44 p.m.
Created at: March 8, 2026, 3:14 p.m.