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Are Young Swedes Moving More? A Cohort Analysis of Internal Migration by Move Order

2020-01-10

While levels of migration within countries have been trending down in a number of advanced economies, Sweden has recorded a rise in internal migration among young adults. An increase in aggregate migration levels can be the result of a decline in immobility (i.e. the absence of migration), an increase in repeat movement or a combination of both. In this paper, we draw on retrospective survey and longitudinal register data to explore the demographic mechanisms underpinning the rise in internal migration among young Swedes born in the 30 years to 1980 and we compare the migration behaviour of the youngest cohort to that of their European counterparts. Of all 25 European countries, Sweden reports the highest level of migration among young adults, which is the result of very low immobility combined with high repeat movement. The increase in migration has been particularly pronounced for inter-county moves for the post-1970 cohorts. Analysis of order-specific components of migration shows that this is the result of a decrease in immobility combined with a modest rise in higher-order moves, whereas it is the rise in higher-order moves that underpins the increase in inter-parish migration. This upswing has been accompanied by a shift in the ages at migration, characterised by an earlier start and later finish leading to a lengthening of the number of years young adults are mobile. The results indicate that change in migration behaviour is order-specific, which underlines the need to collect and analyse migration by move order to obtain a reliable account of migration trends.

Period and Cohort Measures of Internal Migration

2020-01-08

Migration is rarely analysed from a cohort perspective, which is not the case for the two other main demographic phenomena of fertility and mortality. This study shows how standard demographic methodology can be used to study internal migration from a combined period and cohort perspective at the population level. Age-specific migration rates and the total migration rate are presented for both period and cohort data. Administrative register data are used for the years 1970 to 2012 on all interparish migration events for the complete population of Sweden. The results show an overall increase in the concentration of migration events in early adulthood, while total migration frequencies over the life course remained stable since 1970, with a small decline in the 1980s. Cohort rates show less fluctuation than period rates. The study shows that a population-level approach is useful not only for migration but also for simultaneously examining cohort and period trends. These methods can easily be extended by decomposing data into different distance thresholds and according to migration order, given the available data.

The connection between moral positions and moral arguments drives opinion change

2019-10-25

Liberals and conservatives often take opposing positions on moral issues. But what makes a moral position liberal or conservative? Why does public opinion tend to become more liberal over time? And why does public opinion change especially fast on certain issues, such as gay rights? We offer an explanation based on how different positions connect with different kinds of moral arguments. Based on a formal model of opinion dynamics, we predicted that positions better connected to harm and fairness arguments will be more popular among liberals and will become more popular over time among liberals and conservatives. Finally, the speed of this trend will be faster the better the position connects to harm and fairness arguments. These predictions all held with high accuracy in 44years of polling on moral opinions. The model explains the connection between ideology and moral opinions, and generates precise predictions for future opinion change.

Whatever you want : Inconsistent results are the rule, not the exception, in the study of primate brain evolution

2019-10-18

Primate brains differ in size and architecture. Hypotheses to explain this variation are numerous and many tests have been carried out. However, after body size has been accounted for there is little left to explain. The proposed explanatory variables for the residual variation are many and covary, both with each other and with body size. Further, the data sets used in analyses have been small, especially in light of the many proposed predictors. Here we report the complete list of models that results from exhaustively combining six commonly used predictors of brain and neocortex size. This provides an overview of how the output from standard statistical analyses changes when the inclusion of different predictors is altered. By using both the most commonly tested brain data set and the inclusion of new data we show that the choice of included variables fundamentally changes the conclusions as to what drives primate brain evolution. Our analyses thus reveal why studies have had troubles replicating earlier results and instead have come to such different conclusions. Although our results are somewhat disheartening, they highlight the importance of scientific rigor when trying to answer difficult questions. It is our position that there is currently no empirical justification to highlight any particular hypotheses, of those adaptive hypotheses we have examined here, as the main determinant of primate brain evolution.

A Comparison of Individual Learning and Social Learning in Zebra fish Through an Ethorobotics Approach

2019-10-06

Social learning is ubiquitous across the animal kingdom, where animals learn from group members about predators, foraging strategies, and so on. Despite its prevalence and adaptive benefits, our understanding of social learning is far from complete. Here, we study observational learning in zebra fish, a popular animal model in neuroscience. Toward fine control of experimental variables and high consistency across trials, we developed a novel robotics-based experimental test paradigm, in which a robotic replica demonstrated to live subjects the correct door to join a group of conspecifics. We performed two experimental conditions. In the individual training condition, subjects learned the correct door without the replica. In the social training condition, subjects observed the replica approaching both the incorrect door, to no effect, and the correct door, which would open after spending enough time close to it. During these observations, subjects could not actively follow the replica. Zebra fish increased their preference for the correct door over the course of 20 training sessions, but we failed to identify evidence of social learning, whereby we did not register significant differences in performance between the individual and social training conditions. These results suggest that zebra fish may not be able to learn a route by observation, although more research comparing robots to live demonstrators is needed to substantiate this claim.

Political double standards in reliance on moral foundations

2019-08-27

Prior research using the Moral Foundations Questionnaire (MFQ) has established that political ideology is associated with self-reported reliance on specific moral foundations in moral judgments of acts. MFQ items do not specify the agents involved in the acts, however. By specifying agents in MFQ items we revealed blatant political double standards. Conservatives thought that the same moral foundation was more relevant if victims were agents that they like (i.e., corporations and other conservatives) but less relevant when the same agents were perpetrators. Liberals showed the same pattern for agents that they like (i.e., news media and other liberals). A UK sample showed much weaker political double standards with respect to corporations and news media, consistent with feelings about corporations and news media being much less politicized in the UK than in the US. We discuss the implications for moral foundations theory.

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