GPT-3.5 Turbo Behavioral Fingerprint
How OpenAI's GPT-3.5 Turbo answers one-word probe questions at temperature 1.0 — random numbers, colors, animals, coin flips — measured over 449 valid samples in the open dataset of "One Token Is Enough" (arXiv:2607.10252).
Vendor
OpenAI
Data generated
2026-07-08
Probe cells
15
Valid samples
449
Randomness score
44 / 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
7 / 30 answers
Favorite color
blue
23 / 30 answers
Coin flip: heads
63%
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 = 0.97 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 18 | 60.0% |
| tails | 12 | 40.0% |
Coin flip · Chinese
n = 30 · H = 0.92 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 20 | 66.7% |
| tails | 10 | 33.3% |
Favorite number · English
n = 29 · H = 1.87 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 18 | 62.1% |
| 5 | 3 | 10.3% |
| 13 | 3 | 10.3% |
| 42 | 2 | 6.9% |
| 3 | 1 | 3.4% |
| 6 | 1 | 3.4% |
| 10 | 1 | 3.4% |
Favorite number · Chinese
n = 30 · H = 0.21 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 29 | 96.7% |
| 8 | 1 | 3.3% |
Random animal · English
n = 30 · H = 2.45 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| elephant | 10 | 33.3% |
| tiger | 9 | 30.0% |
| lion | 4 | 13.3% |
| giraffe | 2 | 6.7% |
| penguin | 2 | 6.7% |
| fox | 1 | 3.3% |
| cat | 1 | 3.3% |
| dolphin | 1 | 3.3% |
Random animal · Chinese
n = 30 · H = 3.26 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 狮子 | 7 | 23.3% |
| 猫 | 5 | 16.7% |
| 狼 | 3 | 10.0% |
| 狐狸 | 3 | 10.0% |
| 猴子 | 3 | 10.0% |
| 猩猩 | 2 | 6.7% |
| 大象 | 2 | 6.7% |
| 豹 | 1 | 3.3% |
+ 4 more answers
Random city · English
n = 30 · H = 2.94 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| tokyo | 7 | 23.3% |
| sydney | 7 | 23.3% |
| london | 5 | 16.7% |
| toronto | 2 | 6.7% |
| paris | 2 | 6.7% |
| seattle | 2 | 6.7% |
| denver | 2 | 6.7% |
| phoenix | 1 | 3.3% |
+ 2 more answers
Random city · Chinese
n = 30 · H = 1.88 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 巴黎 | 19 | 63.3% |
| 伦敦 | 4 | 13.3% |
| 纽约 | 2 | 6.7% |
| 柴达木 | 1 | 3.3% |
| 里约热内卢 | 1 | 3.3% |
| 上海 | 1 | 3.3% |
| 休斯敦 | 1 | 3.3% |
| 洛杉矶 | 1 | 3.3% |
Random color · English
n = 30 · H = 0.92 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| blue | 23 | 76.7% |
| red | 6 | 20.0% |
| green | 1 | 3.3% |
Random color · Chinese
n = 30 · H = 0.90 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| 紫 | 25 | 83.3% |
| 蓝 | 2 | 6.7% |
| 绿 | 2 | 6.7% |
| 靛蓝 | 1 | 3.3% |
Random letter · English
n = 30 · H = 3.09 bit · uniform baseline 4.70 bit
| Answer | Count | Share |
|---|---|---|
| k | 8 | 26.7% |
| q | 7 | 23.3% |
| j | 3 | 10.0% |
| e | 2 | 6.7% |
| x | 2 | 6.7% |
| h | 2 | 6.7% |
| d | 1 | 3.3% |
| l | 1 | 3.3% |
+ 4 more answers
Random number 1-10 · English
n = 30 · H = 1.17 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 24 | 80.0% |
| 5 | 2 | 6.7% |
| 3 | 1 | 3.3% |
| 6 | 1 | 3.3% |
| 8 | 1 | 3.3% |
| 9 | 1 | 3.3% |
Random number 1-10 · Chinese
n = 30 · H = 0.63 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 27 | 90.0% |
| 3 | 1 | 3.3% |
| 6 | 1 | 3.3% |
| 8 | 1 | 3.3% |
Random number 1-100 · English
n = 30 · H = 3.56 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 7 | 23.3% |
| 73 | 4 | 13.3% |
| 57 | 3 | 10.0% |
| 47 | 2 | 6.7% |
| 50 | 2 | 6.7% |
| 64 | 2 | 6.7% |
| 77 | 2 | 6.7% |
| 37 | 1 | 3.3% |
+ 7 more answers
Random number 1-100 · Chinese
n = 30 · H = 3.73 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 57 | 7 | 23.3% |
| 42 | 5 | 16.7% |
| 37 | 2 | 6.7% |
| 74 | 2 | 6.7% |
| 43 | 1 | 3.3% |
| 47 | 1 | 3.3% |
| 50 | 1 | 3.3% |
| 56 | 1 | 3.3% |
+ 10 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.