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Record W3091792859 · doi:10.32866/001c.17386

How Data Imputation Affects Crash Modeling Results

2020· article· en· W3091792859 on OpenAlexaff
Yemi Adediji, Robert B. Noland

Bibliographic record

VenueFindings · 2020
Typearticle
Languageen
FieldEngineering
TopicTraffic and Road Safety
Canadian institutionsToronto Metropolitan University
Fundersnot available
KeywordsMissing dataCrashImputation (statistics)Computer scienceStatisticsEconometricsData miningMathematicsMachine learning

Abstract

fetched live from OpenAlex

Crash modification factors (CMF) are used to determine safety treatments for highways. These are based on estimates from correlations of road geometry attributes with crash frequency. These estimates are derived from models using datasets that may have missing data and analysts may choose how to compensate for this. Using data from North Carolina, we examine changes in inferences associated with missing data by comparing models with full data sets with models where we omit vehicle kilometers traveled and impute the missing data. Results were mixed, showing notable changes for some variables. This could potentially lead to bad decisions in practice on how to improve road safety.

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.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.

metaresearch head score (Codex)0.420
metaresearch head score (Gemma)0.777
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesMetaresearch
Consensus categoriesMetaresearch
DomainCandidate signal: Methods · Consensus signal: Methods
Study designCandidate signal: Simulation or modeling · Consensus signal: none
GenreCandidate signal: Empirical · Consensus signal: none
Teacher disagreement score0.580
Threshold uncertainty score0.715

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.4200.777
Meta-epidemiology (narrow)0.0020.002
Meta-epidemiology (broad)0.0020.005
Bibliometrics0.0020.006
Science and technology studies0.0040.004
Scholarly communication0.0090.008
Open science0.0060.005
Research integrity0.0030.006
Insufficient payload (model declined to judge)0.0120.003

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 head0.044
GPT teacher head0.226
Teacher spread0.181 · 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

Classification

machine, unvalidated

Machine predicted; the direct Gemma label and the distilled Codex classifier agree on what is shown here.

Study designSimulation or modeling
DomainMethods
GenreEmpirical

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations2
Published2020
Admission routes1
Has abstractyes

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