Estimating Household Trip Rates for Cross-Classification Cells with No Data: Alternative Methods and Their Performance in Prediction of Travel
Bibliographic record
Abstract
This paper investigates a number of alternative methods for addressing the empty-cell problem of traditional cross-classification analysis. Data used in the study were collected in the Toronto region in 1986, 1996, 2001, and 2006. Alternative models, developed on each year’s data, were assessed for how well they predicted travel at the disaggregate household level and at the aggregate traffic analysis zone level in the respective years. In addition, the alternative models estimated on the 1986 data set were assessed for their ability to replicate travel in 1996 and 2006. The results show that a method proposed by Mandel and a model developed in this research, which estimates the household trip rate for an empty cell through a linear combination of the predictions yielded by row and column models, overall give the best forecast performance of travel. They perform better than multiple classification analysis, which is the current industry standard for addressing this shortcoming of traditional cross-classification analysis. The combined categories model also performed very well, particularly in predicting travel at the aggregate level of planning interest.
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 imitationNot 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.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.008 | 0.020 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.002 |
| Bibliometrics | 0.002 | 0.002 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.002 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 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 source (direct Gemma or distilled Codex), 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".