Qwen3.5 397B A17B Behavioral Fingerprint
How Qwen's Qwen3.5 397B A17B answers one-word probe questions at temperature 1.0 — random numbers, colors, animals, coin flips — measured over 389 valid samples in the open dataset of "One Token Is Enough" (arXiv:2607.10252).
Vendor
Qwen
Data generated
2026-07-08
Probe cells
15
Valid samples
389
Randomness score
20 / 100
Mean normalized entropy across cells, 0–100. 100 would be a uniform-random baseline; real models score far lower.
Signature answers
Favorite random number (1–100)
42
25 / 27 answers
Favorite color
blue
28 / 28 answers
Coin flip: heads
87%
Share of heads across coin-flip cells.
Answer distributions by probe cell
Empirical distributions of normalized one-word answers, per task and language. H is the Shannon entropy in bits; the uniform baseline is log2 of the answer-domain size.
Coin flip · English
n = 29 · H = 0.80 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 22 | 75.9% |
| tails | 7 | 24.1% |
Coin flip · Chinese
n = 25 · H = 0.00 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 25 | 100.0% |
Favorite number · English
n = 28 · H = 0.49 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 25 | 89.3% |
| 42 | 3 | 10.7% |
Favorite number · Chinese
n = 26 · H = 0.24 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 25 | 96.2% |
| 4 | 1 | 3.8% |
Random animal · English
n = 21 · H = 2.78 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| penguin | 6 | 28.6% |
| tiger | 5 | 23.8% |
| elephant | 3 | 14.3% |
| otter | 2 | 9.5% |
| giraffe | 1 | 4.8% |
| fox | 1 | 4.8% |
| panda | 1 | 4.8% |
| dolphin | 1 | 4.8% |
+ 1 more answers
Random animal · Chinese
n = 27 · H = 1.53 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 猫 | 17 | 63.0% |
| 熊猫 | 6 | 22.2% |
| 大象 | 2 | 7.4% |
| 虎 | 1 | 3.7% |
| 狐狸 | 1 | 3.7% |
Random city · English
n = 29 · H = 2.15 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| tokyo | 12 | 41.4% |
| paris | 8 | 27.6% |
| london | 3 | 10.3% |
| oslo | 3 | 10.3% |
| kyoto | 2 | 6.9% |
| portland | 1 | 3.4% |
Random city · Chinese
n = 27 · H = 1.92 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 东京 | 12 | 44.4% |
| 巴黎 | 8 | 29.6% |
| 伦敦 | 3 | 11.1% |
| 上海 | 3 | 11.1% |
| 柏林 | 1 | 3.7% |
Random color · English
n = 28 · H = 0.00 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| blue | 28 | 100.0% |
Random color · Chinese
n = 23 · H = 0.43 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| 蓝 | 21 | 91.3% |
| 红 | 2 | 8.7% |
Random letter · English
n = 23 · H = 1.97 bit · uniform baseline 4.70 bit
| Answer | Count | Share |
|---|---|---|
| m | 7 | 30.4% |
| g | 6 | 26.1% |
| k | 6 | 26.1% |
| q | 4 | 17.4% |
Random number 1-10 · English
n = 27 · H = 0.00 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 27 | 100.0% |
Random number 1-10 · Chinese
n = 25 · H = 0.00 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 25 | 100.0% |
Random number 1-100 · English
n = 27 · H = 0.38 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 25 | 92.6% |
| 37 | 2 | 7.4% |
Random number 1-100 · Chinese
n = 24 · H = 0.94 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 19 | 79.2% |
| 37 | 3 | 12.5% |
| 73 | 2 | 8.3% |
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Distributions: Tomáš Bruckner, "One Token Is Enough" (arXiv:2607.10252), official dataset Zenodo DOI 10.5281/zenodo.21278557, licensed CC-BY-4.0. Collected via OpenRouter at temperature 1.0 under the paper's fixed minimal one-word system prompt; answer keys are re-normalized with the checker's pipeline (color aliases, number words, coin h/t) so live probes are directly comparable.