---
license: other
license_name: research-and-demo
base_model: Qwen/Qwen3.5-4B
library_name: peft
tags: [decision, classification, calibration, lora]
---

# Hopper (G)

A general-purpose version of [Hopper](https://huggingface.co/HopitAI/hopper): a LoRA adapter for Qwen3.5-4B that
answers typed decision questions in one forward pass by reading the probability of each option letter, with a
per-kind calibration map. Served with the Hopper code at https://github.com/hopit-ai/hopper.

**Current version: Hopper (G) 1.3** (revision `8b4cd7c`, tag `g-1.3.0`). Hopper (G) 1.2 stays available at
revision `d60a1d6` and is what the Decision Index row below measures.

**Research and demo use only.** These adapters continue training from Hopper 1.0's adapter, whose training data
included passages from RACE (non-commercial research only), and their training data also includes material made with
LLM-based generation. Do not use them commercially.

## Leaderboards (official)

- **[Jev Decision Index](https://huggingface.co/spaces/multimodalart/jev-decision-index)** (edition 0.2.1,
  27 Sep 2026): Hopper (G) 1.2 scores **40.77, #16 of 68**, the highest of the 4B models (Decider 4B: 40.70), from a
  complete self-scored run ([results](https://huggingface.co/datasets/HopitAI/hopper-g-decision-index-results)).
  Hopper (G) 1.3 has not been scored on the Index yet.
- **[JevBench](https://benchmarkheaven.com/jev-models)**: not yet measured. We have asked for Hopper (G) 1.3 to be
  measured as a separate row ([issue #112](https://github.com/fstandhartinger/jevbench/issues/112)). Hopper 1.0's
  official result is 59.43 (v1.4.2.2).

## What changed in 1.3

- **Weights only.** Continued from Hopper (G) 1.2 on 6,400 new code-generated decision items (dated arithmetic, long
  policies with exceptions and precedence, multi-table lookups, ambiguity, probability, safety and judging checklists,
  trade-offs, paraphrase pairs, injected-instruction traps), every answer computed and checked by code, plus
  maintenance and replay of earlier training data under the same retention constraint as 1.2.
- **Serving: unchanged.** Same code as Hopper 1.1.1 / Hopper (G) 1.2, same calibration map (byte-identical), eager
  by default.

## Evaluation (our runs, not official scores)

On our private held-out decision set (2,700 items, nine decision families, built for this purpose and never trained
on), 1.3 scores **+1.7 points over 1.2** (template bootstrap 95% interval +0.5 to +2.9). **This is below the +3.0 we
pre-registered as our own bar for this build**, and a smaller run with a quarter of the new data did about as well
(+2.1), so more of the same data did not help. We release it anyway as a disclosed, qualified release: on our
regression checks against Hopper 1.0 (document reading, numeric, paraphrase, abstention, routing, calibration and a
general-knowledge check) it passes every registered floor, with a pooled gain of +2.3 points (one-sided 95% lower
bound +1.9) and hard-tier calibration 83.5 under the shipped map. None of this predicts a JevBench result.

## Limitations

- English, 4B parameters; it reads options, it does not generate reasoning.
- It rarely concludes "no match" or "cannot be determined" when an explicitly incomplete record leaves a multi-step
  lookup unresolved; 1.3 did not fix this.
- Research and demo use only (see above).

## Revisions

- `8b4cd7c` (tag `g-1.3.0`, full `8b4cd7cc87ef3ec6990245974a91ce6acdd73e4d`): Hopper (G) 1.3, the evaluated adapter bytes.
- Later commit: `adapter_config.json` sets `"task_type": "CAUSAL_LM"` (it was `null`) for the Hub's metadata parser
  only; weights, calibration map and outputs unchanged.
- `d60a1d6`: Hopper (G) 1.2 (the Decision Index row). `060b1bd`: its config-only fix.