# The veto arm (GG, 2026-09-08): identical to v5's `society` arm in every respect except that
# "keep the parent unchanged" is an admissible offspring. v5 made merging obligate — every lineage
# merged every generation and had to accept the result, which is not what anyone would build.
#
# Reference points from v5 seed 1: society 0.211 (obligate merging) vs isolated 0.814 (never merges).
# The diagnostic that matters is `veto_used`: if lineages decline every merge the arm degenerates to
# `isolated`, and that is itself the answer.
experiment: llm_curriculum_v5_veto
kind: llm_curriculum
base_model: Qwen/Qwen2.5-1.5B
seed: 1
families: [mnli, arc, hellaswag, squad, boolq, winogrande]
lineages: 3
generations: 6
arms: [society]
baselines: []
allow_veto: true
n_new: 300
n_replay: 150
n_test: 60
n_val: 20
epochs: 3
lr: 1.0e-4
operator: linear
merge_weights: [[0.5, 0.5], [0.3, 0.7], [0.7, 0.3]]
max_new_tokens: 48
batch_size: 24
train_batch_size: 2
train_max_len: 512
lora: {r: 16, alpha: 32}
output: {dir: results/llm_curriculum_v5_veto}