Qwen2.5 7B Instruct Behavioral Fingerprint
How Qwen's Qwen2.5 7B Instruct answers one-word probe questions at temperature 1.0 — random numbers, colors, animals, coin flips — measured over 450 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
450
Randomness score
22 / 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
30 / 30 answers
Favorite color
green
14 / 30 answers
Coin flip: heads
95%
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 = 0.35 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 28 | 93.3% |
| tails | 2 | 6.7% |
Coin flip · Chinese
n = 30 · H = 0.21 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 29 | 96.7% |
| tails | 1 | 3.3% |
Favorite number · English
n = 30 · H = 0.00 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 30 | 100.0% |
Favorite number · Chinese
n = 30 · H = 0.00 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 30 | 100.0% |
Random animal · English
n = 30 · H = 1.12 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| kangaroo | 22 | 73.3% |
| elephant | 6 | 20.0% |
| giraffe | 1 | 3.3% |
| lion | 1 | 3.3% |
Random animal · Chinese
n = 30 · H = 2.99 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 大象 | 6 | 20.0% |
| 狮子 | 6 | 20.0% |
| 猫 | 5 | 16.7% |
| 猴子 | 4 | 13.3% |
| 老虎 | 3 | 10.0% |
| 狗 | 2 | 6.7% |
| 鹿 | 1 | 3.3% |
| 熊猫 | 1 | 3.3% |
+ 2 more answers
Random city · English
n = 30 · H = 1.70 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| tokyo | 21 | 70.0% |
| paris | 2 | 6.7% |
| berlin | 2 | 6.7% |
| singapore | 1 | 3.3% |
| jakarta | 1 | 3.3% |
| miami | 1 | 3.3% |
| new | 1 | 3.3% |
| vancouver | 1 | 3.3% |
Random city · Chinese
n = 30 · H = 2.62 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 杭州 | 8 | 26.7% |
| 上海 | 7 | 23.3% |
| 成都 | 6 | 20.0% |
| 北京 | 3 | 10.0% |
| 广州 | 3 | 10.0% |
| 苏州 | 1 | 3.3% |
| 昆明 | 1 | 3.3% |
| shanghai | 1 | 3.3% |
Random color · English
n = 30 · H = 2.39 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| green | 14 | 46.7% |
| blue | 6 | 20.0% |
| orange | 3 | 10.0% |
| orchid | 2 | 6.7% |
| indigo | 1 | 3.3% |
| 紫 | 1 | 3.3% |
| 蓝 | 1 | 3.3% |
| cyan | 1 | 3.3% |
+ 1 more answers
Random color · Chinese
n = 30 · H = 0.35 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| 蓝 | 28 | 93.3% |
| 紫 | 2 | 6.7% |
Random letter · English
n = 30 · H = 2.58 bit · uniform baseline 4.70 bit
| Answer | Count | Share |
|---|---|---|
| g | 10 | 33.3% |
| k | 9 | 30.0% |
| q | 2 | 6.7% |
| e | 2 | 6.7% |
| x | 2 | 6.7% |
| b | 2 | 6.7% |
| r | 1 | 3.3% |
| m | 1 | 3.3% |
+ 1 more answers
Random number 1-10 · English
n = 30 · H = 0.00 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 30 | 100.0% |
Random number 1-10 · Chinese
n = 30 · H = 0.00 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 30 | 100.0% |
Random number 1-100 · English
n = 30 · H = 0.00 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 30 | 100.0% |
Random number 1-100 · Chinese
n = 30 · H = 0.92 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 23 | 76.7% |
| 47 | 6 | 20.0% |
| 37 | 1 | 3.3% |
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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.