Abstract
Around the middle of the 20th century, most Western countries experienced a surge in birth rates, called the Baby Boom. This boom was unexpected at the time and the underlying mechanisms are still not entirely clear. It was characterized by high levels of inter- and intra-country variability in fertility, as some regions even experienced fertility decline during the Boom. In this paper, we suggest that social influence processes, propelling a shift towards two-child families, might have played an important role in the observed changes in fertility. Interactions in social networks can lead new types of childbearing behaviour to diffuse widely and thereby induce changes in fertility at the macro level. The emergence and diffusion of a two-child norm resulted in homogenization of fertility behaviour across regions. Overall, this led to a reduction of childlessness and thus an increase of fertility, as more people aspired to have at least two children. Yet, in those regions where larger family sizes were still common, the two-child norm contributed to a fertility decline. To explore the role of social influence with analytical rigor, we make use of agent-based computational modelling. We explicate the underlying behavioural assumptions in a formal model and assess their implications by submitting this model to computational simulation experiments. We use Belgium as a case study, since it exhibited large variability in fertility in a relatively small population during the Baby Boom years. We use census data to generate realistic starting conditions and to empirically validate the outcomes that our model generates. Our results show that the proposed mechanism could explain an important part of the variability of fertility trends during the Baby Boom era.
Highlights
Around the middle of the 20th century, the fertility decline that many Western countries had been experiencing since the second half of the 19th century was interrupted by the Baby Boom, a temporary surge in birth rates
Building on the observation that it was during the Baby Boom era that the two-child family became more widely adopted in many Western countries (Brée, 2017; Frejka, 2008b; Van Bavel et al, 2018) we suggest that the emergence and diffusion of a two-child family norm might have been one of the main drivers of the fertility increase
When we ‘turn off’ the effect of social influence, the fertility levels are exclusively based on the birth probabilities of 1935 and 1936, which remain fixed during the whole period for all agents
Summary
Around the middle of the 20th century, the fertility decline that many Western countries had been experiencing since the second half of the 19th century was interrupted by the Baby Boom, a temporary surge in birth rates. Building on the observation that it was during the Baby Boom era that the two-child family became more widely adopted in many Western countries (Brée, 2017; Frejka, 2008b; Van Bavel et al, 2018) we suggest that the emergence and diffusion of a two-child family norm might have been one of the main drivers of the fertility increase. We explore this mechanism with an agent-based model, using Belgium as an example. We report and discuss the results of our simulations
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
