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Record W4405733642 · doi:10.1080/03610918.2024.2443195

Liu-type shrinkage estimators for mixture of logistic regressions: an osteoporosis study

2024· article· en· W4405733642 on OpenAlex
Elsayed Ghanem, Armin Hatefi, Hamid Usefi

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

VenueCommunications in Statistics - Simulation and Computation · 2024
Typearticle
Languageen
FieldMathematics
TopicStatistical Methods and Inference
Canadian institutionsMemorial University of Newfoundland
Fundersnot available
KeywordsShrinkageLogistic regressionEstimatorStatisticsOsteoporosisShrinkage estimatorEconometricsType (biology)MathematicsMedicineComputer scienceInternal medicineGeology

Abstract

fetched live from OpenAlex

The logistic regression model is one of the most powerful statistical methods for the analysis of binary data. Logistic regression allows using a set of covariates to explain the binary responses. A mixture of logistic regression models is used to fit heterogeneous populations using an unsupervised learning approach. The multicollinearity problem is one of the most common problems in logistic and a mixture of logistic regressions, where the covariates are highly correlated. This problem results in unreliable maximum likelihood estimates for the regression coefficients. This research develops shrinkage methods to deal with the multicollinearity in a mixture of logistic regression models. These shrinkage methods include ridge and Liu-type estimators. Through extensive numerical studies, we show that the developed methods provide more reliable results in estimating the coefficients of the mixture. Finally, we applied shrinkage methods to analyze the status of bone disorders in women aged 50 and older.

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)0.003
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: none
GenreCandidate signal: Methods · Consensus signal: none
Teacher disagreement score0.602
Threshold uncertainty score0.566

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0010.003
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 head0.382
GPT teacher head0.560
Teacher spread0.178 · 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