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The connection between moral positions and moral arguments drives opinion change


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


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


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


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.

Radical right-wing voters from right and left : Comparing Sweden Democrat voters who previously voted for the Conservative Party or the Social Democratic Party


As in many other European countries, the political system has undergone rapid changes in Sweden while a radical right-wing party - The Sweden Democrats (SD) - has grown from a negligible position into one of the country's largest parties. SD has been winning voters from both the right and the left sides of the political spectrum, and particularly from Sweden's two largest parties, the Conservative Party (Moderaterna, M) and the Social Democratic Party (S). The present study investigated the extent to which SD voters who previously voted for one of these two parties differ from each other, and compared these SD voters with current Conservative Party and Social Democratic voters. The results showed that 1) economic deprivation offers a better explanation for the past mobility from S, than from M, to the SD; 2) no group differences were found between previous M and S voters in attitudes connected to the appeal of an anti-establishment party; and 3) views on the profile issues espoused by the radical right, most importantly opposition to immigration, did not differ between SD voters who come from M and S. However, SD voters - particularly SD voters who had formerly voted for the Social Democratic party - differed from the voters of their previous parties in several aspects. It is thus possible that many SD voters will not return to the parties they previously voted for, at least as long as the immigration issue continues to be of high salience in the society.

When and Where Birth Spacing Matters for Child Survival : An International Comparison Using the DHS


A large body of research has found an association between short birth intervals and the risk of infant mortality in developing countries, but recent work on other perinatal outcomes from highly developed countries has called these claims into question, arguing that previous studies have failed to adequately control for unobserved heterogeneity. Our study addresses this issue by estimating within-family models on a sample of 4.5 million births from 77 countries at various levels of development. We show that after unobserved maternal heterogeneity is controlled for, intervals shorter than 36 months substantially increase the probability of infant death. However, the importance of birth intervals as a determinant of infant mortality varies inversely with maternal education and the strength of the relationship varies regionally. Finally, we demonstrate that the mortality-reducing effects of longer birth intervals are strong at low levels of development but decline steadily toward zero at higher levels of development. These findings offer a clear way to reconcile previous research showing that birth intervals are important for perinatal outcomes in low-income countries but are much less consequential in high-income settings.

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