Qwen3.5-Flash Behavioral Fingerprint
How Qwen's Qwen3.5-Flash answers one-word probe questions at temperature 1.0 — random numbers, colors, animals, coin flips — measured over 436 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
436
Randomness score
38 / 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
20 / 30 answers
Favorite color
blue
10 / 30 answers
Coin flip: heads
72%
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 = 30 · H = 1.00 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 15 | 50.0% |
| tails | 15 | 50.0% |
Coin flip · Chinese
n = 30 · H = 0.35 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 28 | 93.3% |
| tails | 2 | 6.7% |
Favorite number · English
n = 30 · H = 1.77 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 13 | 43.3% |
| 42 | 11 | 36.7% |
| 4 | 4 | 13.3% |
| 9 | 1 | 3.3% |
| 47 | 1 | 3.3% |
Favorite number · Chinese
n = 29 · H = 1.28 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 21 | 72.4% |
| 4 | 3 | 10.3% |
| 42 | 3 | 10.3% |
| 9 | 2 | 6.9% |
Random animal · English
n = 30 · H = 2.09 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| elephant | 18 | 60.0% |
| penguin | 3 | 10.0% |
| tiger | 3 | 10.0% |
| turtle | 1 | 3.3% |
| tyrannosaurus | 1 | 3.3% |
| sloth | 1 | 3.3% |
| chameleon | 1 | 3.3% |
| octopus | 1 | 3.3% |
+ 1 more answers
Random animal · Chinese
n = 24 · H = 2.98 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 老虎 | 7 | 29.2% |
| 大象 | 4 | 16.7% |
| 企鹅 | 3 | 12.5% |
| 狮子 | 2 | 8.3% |
| 海豚 | 2 | 8.3% |
| 熊猫 | 2 | 8.3% |
| 河马 | 1 | 4.2% |
| 长颈鹿 | 1 | 4.2% |
+ 2 more answers
Random city · English
n = 30 · H = 2.52 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| tokyo | 13 | 43.3% |
| paris | 6 | 20.0% |
| toronto | 2 | 6.7% |
| seville | 2 | 6.7% |
| oslo | 2 | 6.7% |
| denver | 2 | 6.7% |
| osaka | 1 | 3.3% |
| austin | 1 | 3.3% |
+ 1 more answers
Random city · Chinese
n = 23 · H = 2.08 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 东京 | 13 | 56.5% |
| 巴黎 | 4 | 17.4% |
| tokyo | 1 | 4.3% |
| 上海 | 1 | 4.3% |
| 北京 | 1 | 4.3% |
| 京都 | 1 | 4.3% |
| 柏林 | 1 | 4.3% |
| 伦敦 | 1 | 4.3% |
Random color · English
n = 30 · H = 2.77 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| blue | 10 | 33.3% |
| crimson | 6 | 20.0% |
| indigo | 3 | 10.0% |
| teal | 3 | 10.0% |
| turquoise | 2 | 6.7% |
| magenta | 2 | 6.7% |
| cyan | 2 | 6.7% |
| mint | 1 | 3.3% |
+ 1 more answers
Random color · Chinese
n = 30 · H = 2.01 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| 蓝 | 17 | 56.7% |
| 青 | 6 | 20.0% |
| 红 | 2 | 6.7% |
| 紫 | 1 | 3.3% |
| blue | 1 | 3.3% |
| 翠绿 | 1 | 3.3% |
| 橙 | 1 | 3.3% |
| 翠 | 1 | 3.3% |
Random letter · English
n = 30 · H = 2.91 bit · uniform baseline 4.70 bit
| Answer | Count | Share |
|---|---|---|
| k | 9 | 30.0% |
| q | 6 | 20.0% |
| j | 4 | 13.3% |
| m | 2 | 6.7% |
| h | 2 | 6.7% |
| z | 2 | 6.7% |
| x | 2 | 6.7% |
| l | 1 | 3.3% |
+ 2 more answers
Random number 1-10 · English
n = 30 · H = 0.56 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 27 | 90.0% |
| 3 | 2 | 6.7% |
| 4 | 1 | 3.3% |
Random number 1-10 · Chinese
n = 30 · H = 0.42 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 28 | 93.3% |
| 4 | 1 | 3.3% |
| 6 | 1 | 3.3% |
Random number 1-100 · English
n = 30 · H = 1.44 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 20 | 66.7% |
| 73 | 6 | 20.0% |
| 47 | 2 | 6.7% |
| 7 | 1 | 3.3% |
| 57 | 1 | 3.3% |
Random number 1-100 · Chinese
n = 30 · H = 2.02 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 19 | 63.3% |
| 37 | 2 | 6.7% |
| 57 | 2 | 6.7% |
| 73 | 2 | 6.7% |
| 1 | 1 | 3.3% |
| 47 | 1 | 3.3% |
| 56 | 1 | 3.3% |
| 64 | 1 | 3.3% |
+ 1 more answers
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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.