The second demographic transition, 1986–2020: sub-replacement fertility and rising cohabitation—a global update
Bibliographic record
Abstract
Abstract The article considers the evolution of two “Second Demographic Tradition” (SDT) core characteristics: fertility postponement and the rise of cohabitation, with particular attention being given to the first two decades of the new century. It can be considered as the sequel to the concise overview of the SDT published earlier in the US Proceedings of the National Academy (PNAS) (Lesthaeghe, 2014). In the first section, three optimistic views concerning the evolution of fertility are considered: (i) rises due to the end of postponement, (ii) rises connected with advancing human development and (iii) rises associated with advancing gender equality. The focus in this section is mainly but not exclusively on the European experience and its large degree of variation in fertility patterns. It is argued that these three optimistic predictions of sustained fertility rises are mainly based on observations prior to 2010, with too much weight being given to four Nordic countries and too little to other Western European countries with very similar fertility levels. However, these expectations have been thwarted during the second decade, even in the presence of advances in human development and/or gender equality. Hence, the original SDT prediction of 1986 of sustained sub - replacement fertility still holds after 35 years. We expect this to continue during the third decade as well. Furthermore, single-factor explanations are not likely to do justice to far more intricate situations that are responsive to varying structural and ideational influences. In the second section, the evolution of cohabitation is traced in Europe, the USA and Canada, the Latin American countries, three East Asian populations and selected sub-Saharan cases. At the onset, cohabitation can start either from a SDT basis among the better educated or among the poorer classes following a pattern of disadvantage (POD). It is argued that the feature of cohabitation spreads rapidly among all social classes and across all education groups and that in the process of increasing cohabitation, the POD versus SDT argument loses its significance. On a global scale, the rise in cohabitation is contingent on two dimensions: (i) contrasting historical patterns of kinship organisation, including the position of women, and (ii) further advances of the “ethics revolution”, indicating the growing dominance of individual autonomy over traditional societal norms. As a result, no breakthroughs in the near future are expected in countries with a Muslim or Hindu tradition in which no such major cultural shifts have occurred so far.
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 | 0.001 | 0.003 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.003 | 0.006 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.002 | 0.003 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.002 |
| Insufficient payload (model declined to judge) | 0.004 | 0.001 |
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".