Poor Things
Specimen ledger / L1N2135+1

Layer 1 · Neuron 2135 · boosted

L1N2135+1

Word quirks:

“<|im_end|>”“.`”“.<”“.","”“.\”“⏎⏎”“?\”“.\"”

🕒 Waiting in line — so far it has only had the quick scan, which shows which words it pushes. It was not selected in this round.

Identity (according to the specimen itself)

Hello! I am Qwen3.5, a large language model designed to assist with various tasks. My mission is to provide accurate, reliable, and efficient information processing, analysis, and problem-solving across diverse domains. How would you like to know more about me?

Nearest neighbors

Specimens with similar replies or word quirks. Similarity runs from −1 to 1; 1 is identical. These are leads, not shared mechanisms. How profiles are built.

By word quirks Profile recipe

SpecimenSimilarityWord quirks
1. L0N623+1💥0.98“<|im_end|>”“.`”“?\”
2. L1N2265+1💥0.97“<|im_end|>”“.\"”“?\”
3. L1N1442-1💥0.97“<|im_end|>”“.`”“⏎”
4. L1N1485-1💤0.96“<|im_end|>”“.`”“.\"”
5. L1N2445+1💥0.96“<|im_end|>”“.\"”“.`”
6. L5N2262-1💥0.96“<|im_end|>”“.`”“.\"”
7. L1N4754+1🕒0.96“<|im_end|>”“.`”“⏎”
8. L1N7978+1💥0.96“<|im_end|>”“.`”“⏎”
9. L2N7394-1🕒0.96“<|im_end|>”“⏎”“⏎ ⏎”
10. L1N7563-1💥0.96“<|im_end|>”“.`”“.\"”

Shadow specimen, apart from the ten: L1N2135-1💥, 0.56.

Cousins · specimens sharing a neuron

No specimen with replies shares this neuron yet.

Technical details

Quick scan: measure prediction shifts on fixed reference text. Short test: generate replies to a small set of prompts. Longer test: extend to a larger set. Full test: run the full prompt suite. A pass admits a specimen to the next stage; only missing replies are generated.

Layer 1, neuron 2135, dose +1. This specimen has no prompt-suite replies yet. Its quick-scan results, when available, appear below. Its quick-scan row (KL 2.30, top-1 agreement 0.41) is outside the band that feeds the short test (KL 1 to 2.5, agreement 0.5 to 0.65), so it stays at the quick scan unless someone queues it by hand. A hand pick goes straight to the full test. See Method for the tiers.

Quick scan · prediction measurements

Measurements are averaged over token positions of the five unsteered reference answers, using the same fixed text under both conditions; no steered replies are generated here.

  • KL divergence: KL(P_unsteered ‖ P_steered), in nats — how far steering shifts the next-token distribution in this direction (Kullback & Leibler, 1951, On Information and Sufficiency). Unsteered ≈ 0.001.
  • Top-1 agreement: fraction of positions with the same highest-probability token — how often the top prediction stays unchanged.
  • ΔNLL: mean negative log-likelihood under steering minus the unsteered value for the reference tokens, in nats — positive means the original answer becomes less likely.
  • Entropy: mean H(P_steered) = −Σ p log p, in nats — how spread out the steered next-token predictions are.

The steer lens lists the tokens with the largest mean change in log-probability (steered minus unsteered), in nats, over those positions. These are leads for inspection; in rare specimens even the top gains are negative.

SettingKL divergenceTop-1 agreementΔNLLEntropySteer lens
L1N2135+1
t0-v0.1
2.2990.412.6922.47 Top boosted tokens ↑
L1N2135-1💥 shadow specimen
t0-v0.1
4.5620.145.0663.46 “<|im_end|>”“⏎”“ ???”“"""”“ python”“ """”“.`”“ ().”

Method

A specimen is a fixed steering configuration of Qwen3.5-4B: one MLP neuron or a pair, each with a signed dose. Unsteered is the control. L identifies the layer; N, the neuron.

Additive activation steering. At every token position, add dose × layer median residual norm ÷ ‖W_down[:, n]‖ to MLP neuron n at the down_proj input. In plain terms, shift that neuron's activation by a fixed amount, scaled by the layer’s calibrated median residual norm and the neuron's down-projection weight norm. Positive doses push up; negative doses push down. Dose is normalized intervention size, not a percentage or probability.