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A Response Function That Maps Associative Strengths to Probabilities

2022-07-11

Bridging associative and normative theories of animal learning, I show that an associative system can behave as if performing probabilistic inference by using the function f(V) = 1 − e−cV to transform associative strengths (V) into response probabilities. For example, using this function, an associative system can respond normatively to a compound stimulus AB, given previous separate experiences with the components A and B. The CR probability formulae that result from the proposed function have a normative interpretation in terms of statistical decision theory. The formulae also suggest a normative interpretation of stimulus generalization as a heuristic to infer whether different stimuli are likely to convey redundant or independent information about reinforcement. (PsycInfo Database Record (c) 2022 APA, all rights reserved)

Fading family lines- women and men without children, grandchildren and great-grandchildren in 19th, 20th and 21st Century Northern Sweden

2022-07-01

We studied to what extent family lines die out over the course of 122 years based on Swedish population-level data. Our data included demographic and socioeconomic information for four generations in the Skellefteå region of northern Sweden from 1885 to 2007. The first generation in our sample consisted of men and women born between 1885 and 1899 (N = 5850), and we observed their children, grandchildren, and great-grandchildren. We found that 48% of the first generation did not have any living descendants (great-grandchildren) by 2007. The risk of a family line dying out within the four-generational framework was highest among those who had relatively low fertility in the first generation. Mortality during reproductive years was also a leading reason why individuals in the first generation ended up with a greater risk of not leaving descendants. We identified socioeconomic differences: both the highest-status and the lowest-status occupational groups saw an increased risk of not leaving any descendants. Almost all lineages that made it to the third generation also made it to the fourth generation.

Episodes of liberalization in autocracies : a new approach to quantitatively studying democratization

2022-06-29

This paper introduces a new approach to the quantitative study of democratization. Building on the comparative case-study and large-N literature, it outlines an episode approach that identifies the discrete beginning of a period of political liberalization, traces its progression, and classifies episodes as successful versus different types of failing outcomes, thus avoiding potentially fallacious assumptions of unit homogeneity. We provide a description and analysis of all 383 liberalization episodes from 1900 to 2019, offering new insights on democratic “waves”. We also demonstrate the value of this approach by showing that while several established covariates are valuable for predicting the ultimate outcomes, none explain the onset of a period of liberalization.

Xenophobia among radical and mainstream right-wing party voters : prevalence, correlates and influence on party support

2022-05-20

Considering the current political relevance of anti-immigration sentiments, we examined preference to avoid interacting with immigrants - conceptualized here as a manifestation of xenophobia - among radical (Sweden Democrats, Sverigedemokraterna, N = 2216) and mainstream (Conservative Party, Moderaterna, N = 634) right-wing voters in Sweden. Correlates of xenophobia did not differ between the voter groups or compared to other populations in previous research, suggesting that increased societal focus on immigration has not altered the correlation patterns. Intended Sweden Democrat (vs. Conservative Party) voting correlated with Right-Wing Authoritarianism, institutional distrust, less right-leaning socioeconomic attitudes (in both low- and high-xenophobia subgroups), sexist attitudes (low-xenophobia subgroup), male gender and younger age (high-xenophobia subgroup). In both voter groups, respondents with higher xenophobia expressed on average more sympathy for the Sweden Democrats, perhaps indicating a larger potential voter base. We discuss the interplay of xenophobia and contemporary voting behaviours, and the concept of xenophobia in relation to anti-immigration attitudes.

Pavlovian Summation : Data and Theory

2022-05-19

In summation experiments, responding to a compound stimulus is assessed after conditioning a response to each of its components. This simple experiment poses significant challenges to models of associative learning because of substantial variability in results. Here, I introduce a new method to quantify generalization from components to compound in summation experiments, which I apply to over 250 measurements of summation in rabbits, pigeons, rats, and humans. The analysis confirms that more summation occurs with stimuli from different rather than from the same sensory modality, although this is not the sole determinant of summation. A theoretical analysis shows that this finding is best accounted for by a model that includes both element sharing (Rescorla & Wagner, 1972) and element replacement (Brandon et al., 2000) in stimulus representations. I point out remaining gaps in our empirical and theoretical understanding of summation. 

Women's Experience of Child Death Over the Life Course : A Global Demographic Perspective

2022-01-25

The death of a child affects the well-being of parents and families worldwide, but little is known about the scale of this phenomenon. Using a novel methodology from formal demography applied to data from the 2019 Revision of the United Nations World Population Prospects, we provide the first global overview of parental bereavement, its magnitude, prevalence, and distribution over age for the 1950–2000 annual birth cohorts of women. We project that the global burden of parental bereavement will be 1.6 times lower for women born in 2000 than for women born in 1955. Accounting for compositional effects, we anticipate the largest improvements in regions of the Global South, where offspring mortality continues to be a common life event. This study quantifies an unprecedented shift in the timing of parental bereavement from reproductive to retirement ages. Women in the 1985 cohort and subsequent cohorts will be more likely to lose an adult child after age 65 than to lose a young child before age 50, reversing a long-standing global trend. “Child death” will increasingly come to mean the death of adult offspring. We project persisting regional inequalities in offspring mortality and in the availability of children in later life, a particular concern for parents dependent on support from their children after retirement. Nevertheless, our analyses suggest a progressive narrowing of the historical gap between the Global North and South in the near future. These developments have profound implications for demographic theory and highlight the need for policies to support bereaved older parents.

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