Comments on Manning, Zhang, and Yi’s "Volume and Direction of the Atlantic Slave Trade, 1650-1870”
Bibliographic record
Abstract
Patrick Manning, Yun Zhang and Bowen Yi’s essay is, to our knowledge, the first since Slavevoyages went live in late 2008 to address the question of the size and direction of the largest coerced migration in global history. Given that the Markov Chain Monte Carlo (MCMC) methodology that they employ has moved to center stage of statistical inquiry in this eight-year interval, their work is indeed timely. Our commentary has three parts. First we point out several problems in their use of data from the Trans-Atlantic Slave Trade Database (hereafter TASTDB) on which their estimates are based; second we call attention to our own estimates of the volume of the slave trade which are higher than those mentioned in the essay; and third we argue that, as currently constituted, their work is broadly supportive of the statistical picture that we drew in 2008 albeit without the benefit of MCMC.
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 | 0.004 | 0.037 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.003 |
| Science and technology studies | 0.006 | 0.005 |
| Scholarly communication | 0.004 | 0.004 |
| Open science | 0.003 | 0.003 |
| Research integrity | 0.015 | 0.015 |
| Insufficient payload (model declined to judge) | 0.005 | 0.002 |
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".