MétaCan
Menu
Back to cohort
Record W2182753936

Asymptotic Theory for Linear-Chain Conditional Random Fields

2011· article· en· W2182753936 on OpenAlex

Why this work is in the frame

A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.

affAt least one author lists a Canadian institution in the pinned OpenAlex snapshot.

Bibliographic record

VenueInternational Conference on Artificial Intelligence and Statistics · 2011
Typearticle
Languageen
FieldComputer Science
TopicBayesian Methods and Mixture Models
Canadian institutionsUniversity of Waterloo
Fundersnot available
KeywordsMathematicsCRFSConditional random fieldSequence (biology)Hessian matrixErgodicityApplied mathematicsFeature (linguistics)Consistency (knowledge bases)Exponential familyErgodic theoryInferenceDiscrete mathematicsStatisticsComputer scienceArtificial intelligenceMathematical analysis
DOInot available

Abstract

fetched live from OpenAlex

In this theoretical paper we develop an asymptotic theory for Linear-Chain Condi- tional Random Fields (L-CRFs) and apply it to derive conditions under which the Max- imum Likelihood Estimates (MLEs) of the model weights are strongly consistent. We first define L-CRFs for infinite sequences and analyze some of their basic properties. Then we establish conditions under which ergodic- ity of the observations implies ergodicity of the joint sequence of observations and labels. This result is the key ingredient to derive con- ditions for strong consistency of the MLEs. Interesting findings are that the consistency crucially depends on the limit behavior of the Hessian of the likelihood function and that, asymptotically, the state feature functions do not matter. In this paper, we study asymptotical properties of the Maximum Likelihood Estimates (MLEs) for the model weights. More specifically, we assume that we are given a sequence of observations and labels where the distribution of the labels conditional on the observa- tions follows an L-CRF with known feature functions but unknown weights. In this setting, we investigate conditions under which the MLEs converge to the true weights as the length of the sequences goes to infinity. Note that, to state and to analyze this problem, a def- inition of L-CRFs for infinite sequences is required. Our research is motivated by the following questions: How can the weights and feature functions be jointly estimated in the case where both are unknown? How robust is the training and inference towards a sampling bias (that is, when training and test data come from dierent distributions)? How well is the model iden- tifiable in the presence of noisy data? To tackle these problems of great practical importance, the present paper aims to achieve a better understanding of the simplest case, namely, when the feature functions are known and a sampling bias or noisy data is absent. Furthermore, it provides a theoretical framework and useful techniques to study the more complicated cases. This paper is structured as follows: In Sec. 2 we in- troduce some notation and review the definition of L- CRFs for finite sequences. In Sec. 3 we define L-CRFs for infinite sequences and derive some of their basic properties. Sec. 4 establishes conditions under which ergodicity of the sequence of observations implies er- godicity of the joint sequence of observations and la- bels. In Sec. 5 we apply the previous results to derive conditions under which the MLEs are strongly consis- tent. Sec. 6 concludes the paper.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

Full frame distilled prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.

metaresearch head score (Codex)0.001
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Theoretical or conceptual · Consensus signal: Theoretical or conceptual
GenreCandidate signal: Methods · Consensus signal: Methods
Teacher disagreement score0.477
Threshold uncertainty score0.540

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0010.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.000
Science and technology studies0.0000.000
Scholarly communication0.0000.000
Open science0.0000.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0000.000

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.159
GPT teacher head0.358
Teacher spread0.199 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it