Follow-up Study on Pedestrian Scramble Operations in Calgary, Canada
Bibliographic record
Abstract
Pedestrian scramble operation (PSO) is an exclusive pedestrian signal phase where traffic on all four directions is stopped and pedestrians are allowed to make lateral as well as diagonal crossing. PSO was implemented at two intersections in the City of Calgary in May, 2008. An earlier study analyzed its effects on pedestrian violations and vehicle-pedestrian conflicts six weeks after the implementation of the scramble operation. This paper is a follow up study to determine the longer term effect of this new operation on pedestrian safety. Field observations were again taken one year after the implementation of PSO. Four Poisson regression models were developed to model the number of conflicts and violations. We found some changes in the results from the previous study conducted at the same location. Our results showed that the number of pedestrian-vehicle conflicts and pedestrian violations decreased significantly on weekdays but both pedestrian violations and conflicts increased significantly on weekends after implementation of the scramble operation. Our analysis also revealed that 1.1% of No Right Turn on Red (NRTOR) was violated on weekdays and 3.1% of NRTOR were violated on weekends. The study also looked crashes from three years before and one year after the implementation of PSO and found no significant change in the number of crashes per year. This result is not surprising since none of the crashes recorded involved pedestrians.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot 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.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.004 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.003 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.004 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
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.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
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".