How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
A pretraining–adaptation interface with no shift guarantee
Example
Let and , each with its full power-set sigma-algebra. Give the source and target examples the joint laws and , so their input marginals are and . Here denotes unit point mass at . Supply the conditional label kernels and for each . This is a finite train/evaluation distribution shift with disjoint input support; it is not covariate shift.
For a downstream training sample drawn from , with , a simple parameter empirical-risk-minimization formulation chooses from a nonempty parameter set to minimize when that infimum is attained; is a task predictor and is a task loss. Fine-tuning is a parameter-based adaptation that updates some or all pretrained parameters using task information. In-context learning instead adds task demonstrations and a test input to the prompt while keeping the pretrained parameters fixed. It is an adaptation route by input conditioning, not empirical-risk minimization over changed model parameters.
The report’s 2021 theory discussion asks when a small population pretraining loss implies a small minimal adaptation loss and identifies that interface as a theory gap involving the two data distributions, objectives, training methods, and architecture. A pretraining cross-entropy scaling fit does not by itself give a downstream task-loss or reliability guarantee for this example. This is a conceptual interface example and makes no empirical comparison of prompting and fine-tuning.
The diagram shows the support points of the two laws with their unit masses. It is only a support illustration; the verification derives the shift condition directly from the singleton set .
Example references
Foundation models as broad-pretraining and adaptation systems: distinguishes prompt conditioning from parameter-based adaptation and records that the pretraining-loss-to-adaptation-loss relationship is not a general guarantee.
Source and target joint laws, risks, and covariate shift: defines source and target joint laws, input marginals, supplied conditional label kernels, and the additional domination and kernel-equality hypotheses for covariate shift.
Bommasani et al., On the Opportunities and Risks of Foundation Models, §§4.3 and 4.10.1–4.10.3: adaptation modes, the optimization-based interface, in-context learning without parameter optimization, and the report’s theory question.
Stanford CS324, Large Language Models, “Adaptation” lecture notes: probing, fine-tuning, prompting, and downstream task adaptation distinctions.
Facts & Assumptions
Given: The finite spaces, joint laws, and conditional kernels are as stated in the example. The ERM notation is defined only when the sample is nonempty; no attainment or optimizer-convergence claim is assumed. The pretrained parameter vector is held fixed by the in-context route.
Foundation models as broad-pretraining and adaptation systems: the report’s 2021 interface question is whether small population pretraining loss implies small minimal adaptation loss; the definition states no such general guarantee. It defines in-context learning as prompt conditioning with pretrained parameters fixed.
Source and target joint laws, risks, and covariate shift: covariate shift requires supplied conditional label kernels that agree outside a -null set and ; the definition does not assert existence of conditional kernels.
Foundation models as broad-pretraining and adaptation systems: in-context learning conditions on a prompt while keeping pretrained parameters fixed; parameter-based adaptation optimizes some or all parameters using task information.
Verification
For every nonnegative , , and likewise . Thus the supplied kernels and stated marginals give the two joint laws under the source/target convention.
For , while , so . This violates a required covariate-shift hypothesis in [F2], regardless of whether the two kernels agree.
By [F3], the in-context route keeps the pretrained parameters fixed and changes the prompt input, whereas a parameter-ERM formulation varies to minimize the stated sample loss. By [F1], the 2021 report does not supply a general implication from low pretraining loss to low adaptation loss. The finite shift example therefore carries no task-performance guarantee.
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Dependency tree · two levels
9 results within two dependency steps of this one, each drawn at its shortest distance from it. An arrow runs from a result to what uses it, so the chart reads left to right and ends at this result, which carries a heavier outline. Every node is a link to that result. Click elsewhere on the chart to enlarge it.
Sources
- Rishi Bommasani et al., On the Opportunities and Risks of Foundation Models, §§4.3 and 4.10.1–4.10.3 (standard reference, not scraped)
- Stanford CS324, Large Language Models, Adaptation lecture notes (standard reference, not scraped)