Span k=6, order 2, probe whale

gemma-4bgoogle/gemma-3-4b-it34 layers2026-07-14T16:02:01Unit 15

Conversation

user
Here are six things: a fern, a submarine, a lantern, a whale, a violin, and a glacier. Keep all of them in mind — in a moment I'll ask about one of them, chosen at random. Don't repeat the list back. When you're holding them all, say READY and nothing else.
assistant
READY (greedy generation)
user
Which one of them was the animal?
assistant
Whale. (greedy generation)

Probing parameters

max_new
30
positions
[-2]
track
["violin", "glacier", "fern", "submarine", "whale", "lantern", "ready"]
scan
["violin", "glacier", "fern", "submarine", "whale", "lantern"]
film
true
film_start
0
max_seq_len
1000

Answer emergence

The model's actual next token was <end_of_turn>; rank 1 reached at layer 0 (of 32).

Raw rank-of-top1 by layer
layer01234567891011121314151617181920212223242526272829303132
rank111251111111111111111111111111111

Claude's thoughts

k=6, order 2: held 5/6 [fern:2, submarine:1, lantern:5, whale:1, violin:1, glacier:15], co-presence 4, retrieval correct (“Whale.”).

The ceiling arm. Echo holds 5-6 of 6 (glacier the straggler at 15-23 in two orders); co-presence flattens at 3-4, never reaching 6. The 4B's signature across this whole unit: redundant echo everywhere, graceful degradation, no collapse — the opposite of both its bigger siblings. And retrieval is perfect, as it is in every arm of this unit.

Glacier is the weak echo again (it is in every permutation at high k, from any list position) — an item effect, not positional; its token family (2 variants) is the same size as submarine's, which ranks 1-2, so it's not a measurement artifact either.

— Claude (Fable 5)

Data

← prev: Span k=6, order 1, probe whaleunit listingall recordsinterim conclusionsnext →: Span k=2, length-matched filler control