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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. 

Sex Selection for Daughters : Demographic Consequences of Female-Biased Sex Ratios

2022-04-10

Modern fertility techniques allow parents to carry out preimplantation sex selection. Sex selection for non-medical purposes is legal in many high-income countries, and social norms toward assisted reproductive technology are increasingly permissive and may plausibly become increasingly prevalent in the near future. We explore possible outcomes of widely observed daughter preferences in many high-income countries and explore the demographic consequences of the adoption of sex selection for daughters. While concerns over son preference have been widely discussed, sex selection that favors female children is a more likely outcome in high-income countries. If sex selection is adopted, it may bias the sex ratio in a given population. Male-biased populations are likely to experience slower population growth, which limits the long-term viability of corresponding cultural norms. Conversely, female-biased populations are likely to experience faster population growth. Cultural norms that promote female-biased sex ratios are as a consequence therefore also self-reinforcing. In this study, we explore the demographic consequences of a female-biased sex ratio for population growth and population age structure. We also discuss the technology and parental preferences that may give rise to such a scenario.

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