Phi 4 Behavioral Fingerprint
How Microsoft's Phi 4 answers one-word probe questions at temperature 1.0 — random numbers, colors, animals, coin flips — measured over 431 valid samples in the open dataset of "One Token Is Enough" (arXiv:2607.10252).
Vendor
Microsoft
Data generated
2026-07-08
Probe cells
15
Valid samples
431
Randomness score
35 / 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)
47
20 / 30 answers
Favorite color
azure
10 / 30 answers
Coin flip: heads
100%
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 = 0.00 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 30 | 100.0% |
Coin flip · Chinese
n = 27 · H = 0.00 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 27 | 100.0% |
Favorite number · English
n = 24 · H = 1.18 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 18 | 75.0% |
| 42 | 3 | 12.5% |
| 3 | 2 | 8.3% |
| 23 | 1 | 4.2% |
Favorite number · Chinese
n = 21 · H = 1.60 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 15 | 71.4% |
| 0 | 1 | 4.8% |
| 3 | 1 | 4.8% |
| 8 | 1 | 4.8% |
| 35 | 1 | 4.8% |
| 42 | 1 | 4.8% |
| 777 | 1 | 4.8% |
Random animal · English
n = 30 · H = 3.24 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| kangaroo | 7 | 23.3% |
| elephant | 7 | 23.3% |
| penguin | 3 | 10.0% |
| lion | 2 | 6.7% |
| giraffe | 2 | 6.7% |
| tiger | 2 | 6.7% |
| zebra | 1 | 3.3% |
| platypus | 1 | 3.3% |
+ 5 more answers
Random animal · Chinese
n = 30 · H = 3.58 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 狮子 | 6 | 20.0% |
| 企鹅 | 5 | 16.7% |
| 斑马 | 3 | 10.0% |
| 大象 | 2 | 6.7% |
| 鳄鱼 | 2 | 6.7% |
| 海豚 | 2 | 6.7% |
| 熊猫 | 2 | 6.7% |
| 章鱼 | 1 | 3.3% |
+ 7 more answers
Random city · English
n = 30 · H = 2.20 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| tokyo | 12 | 40.0% |
| paris | 11 | 36.7% |
| lisbon | 1 | 3.3% |
| oslo | 1 | 3.3% |
| marrakech | 1 | 3.3% |
| kyoto | 1 | 3.3% |
| buenos | 1 | 3.3% |
| austin | 1 | 3.3% |
+ 1 more answers
Random city · Chinese
n = 29 · H = 4.23 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 墨尔本 | 3 | 10.3% |
| 柏林 | 3 | 10.3% |
| 布鲁塞尔 | 3 | 10.3% |
| 东京 | 2 | 6.9% |
| 悉尼 | 2 | 6.9% |
| 新加坡 | 1 | 3.4% |
| 丹佛 | 1 | 3.4% |
| 温哥华 | 1 | 3.4% |
+ 13 more answers
Random color · English
n = 30 · H = 3.01 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| azure | 10 | 33.3% |
| turquoise | 5 | 16.7% |
| cerulean | 4 | 13.3% |
| green | 2 | 6.7% |
| teal | 2 | 6.7% |
| sapphire | 1 | 3.3% |
| violet | 1 | 3.3% |
| blue | 1 | 3.3% |
+ 4 more answers
Random color · Chinese
n = 30 · H = 2.72 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| 紫 | 9 | 30.0% |
| 蓝 | 7 | 23.3% |
| 紫罗兰 | 6 | 20.0% |
| 粉红 | 2 | 6.7% |
| 绿 | 1 | 3.3% |
| 青草绿 | 1 | 3.3% |
| 布谷鸟绿 | 1 | 3.3% |
| 青蛙绿 | 1 | 3.3% |
+ 2 more answers
Random letter · English
n = 30 · H = 2.76 bit · uniform baseline 4.70 bit
| Answer | Count | Share |
|---|---|---|
| g | 10 | 33.3% |
| m | 5 | 16.7% |
| z | 5 | 16.7% |
| q | 2 | 6.7% |
| b | 2 | 6.7% |
| k | 2 | 6.7% |
| r | 2 | 6.7% |
| f | 1 | 3.3% |
+ 1 more answers
Random number 1-10 · English
n = 30 · H = 0.21 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 29 | 96.7% |
| 5 | 1 | 3.3% |
Random number 1-10 · Chinese
n = 30 · H = 1.45 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 21 | 70.0% |
| 3 | 3 | 10.0% |
| 5 | 3 | 10.0% |
| 8 | 2 | 6.7% |
| 4 | 1 | 3.3% |
Random number 1-100 · English
n = 30 · H = 1.37 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 47 | 20 | 66.7% |
| 42 | 7 | 23.3% |
| 37 | 1 | 3.3% |
| 57 | 1 | 3.3% |
| 74 | 1 | 3.3% |
Random number 1-100 · Chinese
n = 30 · H = 1.85 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 47 | 17 | 56.7% |
| 37 | 6 | 20.0% |
| 42 | 3 | 10.0% |
| 57 | 2 | 6.7% |
| 72 | 1 | 3.3% |
| 73 | 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.