Factors Influencing Boys' Age at First Intercourse and Condom Use in the Shantytowns of Recife, Brazil
Bibliographic record
Abstract
Despite the general recognition that the sexual practices of adolescent boys place them at high risk of acquiring sexually transmitted infections (STIs), including HIV, and of causing unwanted pregnancies, advances in mapping their sexual behaviors have been slow. This study uses data recently collected from low-income areas of the city of Recife, Brazil, to study boys' age at first sexual intercourse and factors that hinder their use of condoms. These boys become sexually active at early ages, and despite their general awareness of HIV, they rarely use condoms, especially at ages younger than 15. Sustained family involvement in guiding boys is associated with later first intercourse and an increased use of condoms. Boys who describe themselves as shy with girls have later first intercourse, although the probability of their using condoms does not differ from that of other boys of their age. Higher socioeconomic status leads to earlier sexual activity for boys (in contrast with girls), but also to a greater likelihood of using condoms during first intercourse.
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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 | 0.000 | 0.003 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".