Vehicle-pedestrian accidents at signalized intersections in Montréal
Notice bibliographique
Résumé
Pedestrian safety is a topic of growing concern. To better understand pedestrian safety and the variables that affect it, this thesis had four main objectives. The first objective was to build a database to be used for the analysis of pedestrian safety. The database built consisted of 1,875 signalized intersections (75% of all signalized intersections on the island), randomly distributed throughout the island of Montreal. Manual vehicular and pedestrian counts were provided by local authorities for these intersections, but they also needed to be visited individually, so that geometric data could be recorded for each intersection. This is the largest data set that has ever been assembled for a pedestrian safety analysis. The second objective was to use automatic counters to extrapolate manual pedestrian counts taken during peak periods, to full 24 hour average daily counts through the use of expansion factors. By placing automatic counters at six different locations throughout the city of Montreal for one full year, various expansion factors were generated (monthly, daily and hourly). The third objective was to investigate the effect of traffic exposure measures, geometric designs and traffic controls on vehicle-pedestrian collision occurrence at signalized intersections. To investigate the impact of vehicle movements on pedestrian accidents, three separate definitions of risk exposure were used: completely aggregated flows, motor-vehicle flows aggregated by movement type (left, right and through movements) and disaggregated flows analyzing potential conflicts between motor vehicles and pedestrians. Various negative binomial (NB) models were fitted to the data with and without geometric design characteristics. Among other findings, vehicular traffic is found to be the main contributing factor in accordance with previous works. Significant geometric properties included pedestrian phasing, exclusive left turn lanes, commercial entrances and exits, total crossing distance, curb extension and number of lanes. Exclusive left turn lanes, pedestrian phasing and curb extensions were found to decrease pedestrian accidents, whereas longer crossing distances, number of lanes and more commercial entrances and exits were found to increase pedestrian-vehicular accidents after controlling for vehicular and pedestrian flows. The final objective was to estimate pedestrian activity at signalized intersections based on built environment attributes. Using both a log-linear and negative binomial regression, it was found that pedestrian activity could be estimated by several land-use, transit, demographic and weather variables; including: population, commercial space, open space, subway presence, bus stations, schools, percent major arterials, number of street segments, presence of a 4-way intersections, presence of precipitation and presence of windy conditions. These findings support other studies done in this field.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,001 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,002 | 0,003 |
| Études des sciences et des technologies | 0,001 | 0,000 |
| Communication savante | 0,001 | 0,000 |
| Science ouverte | 0,001 | 0,001 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».