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NovaSearch/stella_en_1.5B_v5

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Primitive: /encode · Encode · Qwen2

We released a Jasper and Stella model technology report and code.(2025.1)

Dense

Overview

Hardware: — drives latency, throughput & cost

Size1.5B params
Tasks /encode
Licensemit
Latency258 ms
Throughput12.8K tok/s
Cost$0.017 /1M tok

Cost is approximate — computed from list GPU prices; your actual price depends on the provider you deploy SIE with.

Embedding

Output typesDense
Dimensionsdense: 1,024
Max sequence length512
Inputstext

Benchmarks

CQADupstackPhysicsRetrieval

scientific retrieval en

Duplicate question retrieval from StackExchange Physics

Corpus: 38,314 Queries: 1,039
Quality
ndcg at 10 0.5191
map at 10 0.4497
mrr at 10 0.5046
Performance L4 b1 c16
Corpus 11.7K tok/s
Corpus p50 180.9ms
Query 2.0K tok/s
Query p50 73.7ms
Reference →

CosQA

technology retrieval en

Code search with natural language queries

Corpus: 6,267 Queries: 500
Quality
ndcg at 10 0.3259
map at 10 0.2444
mrr at 10 0.2524
Performance L4 b1 c16
Corpus 8.5K tok/s
Corpus p50 100.4ms
Query 1.2K tok/s
Query p50 71.8ms
Reference →

FiQA2018

finance retrieval en

Financial opinion mining and question answering

Corpus: 57,599 Queries: 648
Quality
ndcg at 10 0.5961
map at 10 0.5123
mrr at 10 0.6681
Performance L4 b1 c16
Corpus 13.0K tok/s
Corpus p50 222.0ms
Query 2.2K tok/s
Query p50 74.6ms
Reference →

LegalBenchConsumerContractsQA

legal retrieval en

Question answering on consumer contracts

Corpus: 153 Queries: 396
Quality
ndcg at 10 0.8108
map at 10 0.7616
mrr at 10 0.7616
Performance L4 b1 c16
Corpus 16.7K tok/s
Corpus p50 522.2ms
Query 2.7K tok/s
Query p50 84.9ms
Reference →

NFCorpus

medical retrieval en

Biomedical literature search from NutritionFacts.org

Corpus: 3,593 Queries: 323
Quality
ndcg at 10 0.4215
map at 10 0.1643
mrr at 10 0.6201
Performance L4 b1 c16
Corpus 13.9K tok/s
Corpus p50 185.3ms
Query 849 tok/s
Query p50 51.9ms
Reference →

NanoFiQA2018Retrieval

finance retrieval en

Smaller subset of the FiQA financial QA dataset

Quality
ndcg at 10 0.6555
map at 10 0.5859
mrr at 10 0.6764
Performance L4 b1 c16
Corpus 1.2K tok/s
Corpus p50 1.5s
Query 1.1K tok/s
Query p50 117.8ms
Reference →

SCIDOCS

scientific retrieval en

Citation prediction, document classification, and recommendation for scientific papers

Corpus: 25,656 Queries: 1,000
Quality
ndcg at 10 0.2666
map at 10 0.1649
mrr at 10 0.4293
Performance L4 b1 c16
Corpus 12.5K tok/s
Corpus p50 257.9ms
Query 2.0K tok/s
Query p50 77.3ms
Reference →

SciFact

scientific retrieval en

Scientific claim verification using research literature

Corpus: 5,183 Queries: 300
Quality
ndcg at 10 0.8039
map at 10 0.7570
mrr at 10 0.7651
Performance L4 b1 c16
Corpus 12.8K tok/s
Corpus p50 356.8ms
Query 3.0K tok/s
Query p50 80.0ms
Reference →

StackOverflowQA

technology retrieval en

Programming question answering from Stack Overflow

Corpus: 19,931 Queries: 1,994
Quality
ndcg at 10 0.9165
map at 10 0.9008
mrr at 10 0.9008
Performance L4 b1 c16
Corpus 14.2K tok/s
Corpus p50 265.9ms
Query 15.6K tok/s
Query p50 329.0ms
Reference →

Open source inference for agents

Open-source inference for the models behind your agents. Run it yourself, or let us run it for you.

Github 3.3K

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