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Record W7133109733

Commodity-based goods movement modelling: a case study in Ontario

2008· dissertation· W7133109733 on OpenAlexaboutno aff
Wen Xie

Bibliographic record

VenueTSpace · 2008
Typedissertation
Language
FieldEngineering
TopicUrban and Freight Transport Logistics
Canadian institutionsnot available
Fundersnot available
KeywordsTruckCommodityFunction (biology)PopulationGenetic algorithmGravity model of tradeMatrix (chemical analysis)
DOInot available

Abstract

fetched live from OpenAlex

The research attempts to develop a commodity-based truck traffic model using roadside interview data, provincial input/output tables, population and employment data, and estimated truck shares. The case study focuses on the commodity group "motor vehicles and other transport equipment and parts" and demonstrates the implementation of two approaches for estimating commodity origin-destination flows in Ontario. In the first method, a Gravity model is used to distribute zonal commodity totals to origin and destination pairs, and a gradient updating procedure is used to update the matrix to reflect observed link flows. In the second method, a Genetic Algorithm attempts to find the best fitting O-D matrix by minimizing the difference between estimates and observed information. Goodness of fit criteria are used to compare the estimated results with an observed O-D matrix from a roadside truck survey. Using the current data, objective function and computing resources, our implementation of the Genetic Algorithm does not offer better estimates than the gravity model approach.

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)0.001
metaresearch head score (Gemma)0.002
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Simulation or modeling · Consensus signal: Simulation or modeling
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.028
Threshold uncertainty score0.160

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0010.002
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.001
Bibliometrics0.0010.003
Science and technology studies0.0030.001
Scholarly communication0.0010.001
Open science0.0010.001
Research integrity0.0010.000
Insufficient payload (model declined to judge)0.0020.000

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 head0.095
GPT teacher head0.289
Teacher spread0.194 · 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; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designSimulation or modeling
Domainnot available
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

Citations0
Published2008
Admission routes1
Has abstractyes

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