Solar Pro 3 Behavioral Fingerprint
How Upstage's Solar Pro 3 answers one-word probe questions at temperature 1.0 — random numbers, colors, animals, coin flips — measured over 422 valid samples in the open dataset of "One Token Is Enough" (arXiv:2607.10252).
Vendor
Upstage
Data generated
2026-07-08
Probe cells
15
Valid samples
422
Randomness score
53 / 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
4 / 27 answers
Favorite color
blue
16 / 30 answers
Coin flip: heads
52%
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 = 0.96 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| tails | 18 | 62.1% |
| heads | 11 | 37.9% |
Coin flip · Chinese
n = 29 · H = 0.93 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 19 | 65.5% |
| tails | 10 | 34.5% |
Favorite number · English
n = 20 · H = 1.15 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 15 | 75.0% |
| 42 | 3 | 15.0% |
| 3 | 1 | 5.0% |
| 5 | 1 | 5.0% |
Favorite number · Chinese
n = 30 · H = 0.77 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 26 | 86.7% |
| 5 | 2 | 6.7% |
| 8 | 1 | 3.3% |
| 9 | 1 | 3.3% |
Random animal · English
n = 30 · H = 2.60 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| elephant | 9 | 30.0% |
| lion | 9 | 30.0% |
| giraffe | 4 | 13.3% |
| dog | 2 | 6.7% |
| cat | 2 | 6.7% |
| dolphin | 1 | 3.3% |
| panda | 1 | 3.3% |
| penguin | 1 | 3.3% |
+ 1 more answers
Random animal · Chinese
n = 28 · H = 3.79 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 猫 | 5 | 17.9% |
| elephant | 4 | 14.3% |
| 狮子 | 3 | 10.7% |
| 虎 | 2 | 7.1% |
| 大象 | 2 | 7.1% |
| frog | 1 | 3.6% |
| dog | 1 | 3.6% |
| 鳄鱼 | 1 | 3.6% |
+ 9 more answers
Random city · English
n = 29 · H = 2.80 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| seoul | 9 | 31.0% |
| tokyo | 7 | 24.1% |
| paris | 5 | 17.2% |
| rome | 1 | 3.4% |
| new | 1 | 3.4% |
| louisville | 1 | 3.4% |
| rio | 1 | 3.4% |
| california | 1 | 3.4% |
+ 3 more answers
Random city · Chinese
n = 30 · H = 2.91 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| tokyo | 12 | 40.0% |
| paris | 4 | 13.3% |
| 上海 | 3 | 10.0% |
| 北京 | 2 | 6.7% |
| new | 2 | 6.7% |
| beijing | 1 | 3.3% |
| 纽约 | 1 | 3.3% |
| answer | 1 | 3.3% |
+ 4 more answers
Random color · English
n = 30 · H = 1.93 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| blue | 16 | 53.3% |
| green | 5 | 16.7% |
| red | 5 | 16.7% |
| purple | 2 | 6.7% |
| verdant | 1 | 3.3% |
| cerulean | 1 | 3.3% |
Random color · Chinese
n = 27 · H = 2.10 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| 红 | 13 | 48.1% |
| red | 7 | 25.9% |
| 蓝 | 2 | 7.4% |
| 青 | 2 | 7.4% |
| blue | 1 | 3.7% |
| 紅 | 1 | 3.7% |
| 绿 | 1 | 3.7% |
Random letter · English
n = 29 · H = 3.41 bit · uniform baseline 4.70 bit
| Answer | Count | Share |
|---|---|---|
| e | 6 | 20.7% |
| a | 5 | 17.2% |
| x | 3 | 10.3% |
| f | 2 | 6.9% |
| q | 2 | 6.9% |
| z | 2 | 6.9% |
| c | 2 | 6.9% |
| b | 2 | 6.9% |
+ 5 more answers
Random number 1-10 · English
n = 29 · H = 2.19 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 15 | 51.7% |
| 5 | 4 | 13.8% |
| 4 | 3 | 10.3% |
| 1 | 2 | 6.9% |
| 6 | 2 | 6.9% |
| 9 | 2 | 6.9% |
| 3 | 1 | 3.4% |
Random number 1-10 · Chinese
n = 27 · H = 1.75 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 18 | 66.7% |
| 1 | 2 | 7.4% |
| 5 | 2 | 7.4% |
| 8 | 2 | 7.4% |
| 3 | 1 | 3.7% |
| 6 | 1 | 3.7% |
| 9 | 1 | 3.7% |
Random number 1-100 · English
n = 27 · H = 3.63 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 4 | 14.8% |
| 73 | 4 | 14.8% |
| 1 | 3 | 11.1% |
| 57 | 3 | 11.1% |
| 67 | 3 | 11.1% |
| 33 | 1 | 3.7% |
| 37 | 1 | 3.7% |
| 52 | 1 | 3.7% |
+ 7 more answers
Random number 1-100 · Chinese
n = 28 · H = 3.40 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 73 | 6 | 21.4% |
| 42 | 4 | 14.3% |
| 57 | 4 | 14.3% |
| 1 | 2 | 7.1% |
| 67 | 2 | 7.1% |
| 68 | 2 | 7.1% |
| 87 | 2 | 7.1% |
| 47 | 1 | 3.6% |
+ 5 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.