Dimensions over categories: a meta-analysis of taxometric research.

Taxometric procedures have been used extensively to investigate whether individual differences in personality and psychopathology are latently dimensional or categorical ('taxonic'). We report the first meta-analysis of taxometric research, examining 317 findings drawn from 183 articles that employed an index of the comparative fit of observed data to dimensional and taxonic data simulations. Findings supporting dimensional models outnumbered those supporting taxonic models five to one. There were systematic differences among 17 construct domains in support for the two models, but psychopathology was no more likely to generate taxonic findings than normal variation (i.e. individual differences in personality, response styles, gender, and sexuality). No content domain showed aggregate support for the taxonic model. Six variables - alcohol use disorder, intermittent explosive disorder, problem gambling, autism, suicide risk, and pedophilia - emerged as the most plausible taxon candidates based on a preponderance of independently replicated findings. We also compared the 317 meta-analyzed findings to 185 additional taxometric findings from 96 articles that did not employ the comparative fit index. Studies that used the index were 4.88 times more likely to generate dimensional findings than those that did not after controlling for construct domain, implying that many taxonic findings obtained before the popularization of simulation-based techniques are spurious. The meta-analytic findings support the conclusion that the great majority of psychological differences between people are latently continuous, and that psychopathology is no exception.

Moral Identity Predicts Adherence to COVID-19 Mitigation Procedures Depending on Political Ideology: A Comparison Between the USA and New Zealand.

Reducing the spread of infectious viruses (e.g., COVID-19) can depend on societal compliance with effective mitigations. Identifying factors that influence adherence can inform public policy. In many cases, public health messaging has become highly moralized, focusing on the need to act for the greater good. In such contexts, a person's moral identity may influence behavior and serve to increase compliance through different mechanisms: if a person sees compliance as the right thing to do (internalization) and/or if a person perceives compliance as something others will notice as the right thing to do (symbolization). We argue that in societies that are more politically polarized, people's political ideology may interact with their moral identity to predict compliance. We hypothesized that where polarization is high (e.g., USA), moral identity should positively predict compliance for liberals to a greater extent than for conservatives. However, this effect would not occur where polarization is low (e.g., New Zealand). Moral identity, political ideology, and support for three different COVID-19 mitigation measures were assessed in both nations (N = 1,980). Results show that while moral identity can influence compliance, the political context of the nation must also be taken into account.

Development and validation of the Harm Concept Breadth Scale: Assessing individual differences in harm inflation.

Three studies (Ns = 350, 301 & 341) examined the reliability, validity, and correlates of a new measure of harm inflation, the individual differences counterpart of 'concept creep'. The Harm Concept Breadth Scale (HCBS) assesses variability in the expansiveness of concepts of harm (i.e., bullying, mental disorder, prejudice, trauma), such that these concepts refer to a wider range of phenomena among people scoring high on the scale. Study 1 developed 66 vignettes representing potential instances of the four concepts, selected optimal subsets of 10 vignettes for each concept, and demonstrated satisfactory internal consistency of the subscales. Study 2 demonstrated that the HCBS had excellent internal consistency, and established construct validity through associations with measures of moral foundations, justice sensitivity, general category inclusiveness, and political orientation. Study 3 employed participants from a different national background and further clarified the correlates of the HCBS via measures of empathy, moral expansiveness, and the Big Five personality traits. The findings indicate that concept breadth is a reliably measurable individual difference variable with weak to moderate associations with harm-based morality, prosocial concern, political liberalism, female gender, and negative emotionality. The HCBS is a valid psychometric instrument for examining the causes and implications of harm inflation.

Twentieth century morality: The rise and fall of moral concepts from 1900 to 2007.

Trends in the cultural salience of morality across the 20th century in the Anglophone world, as reflected in changing use of moral language, were explored using the Google Books (English language) database. Relative frequencies of 304 moral terms, organized into six validated sets corresponding to general morality and the five moral domains proposed by moral foundations theory, were charted for the years 1900 to 2007. Each moral language set displayed unique, often nonlinear historical trajectories. Words conveying general morality (e.g., good, bad, moral, evil), and those representing Purity-based morality, implicating sanctity and contagion, declined steeply in frequency from 1900 to around 1980, when they rebounded sharply. Ingroup-based morality, emphasizing group loyalty, rose steadily over the 20th century. Harm-based morality, focused on suffering and care, rose sharply after 1980. Authority-based morality, which emphasizes respect for hierarchy and tradition, rose to a peak around the social convulsions of the late 1960s. There were no consistent tendencies for moral language to become more individualist or less grounded in concern for social order and cohesion. These differing time series suggest that the changing moral landscape of the 20th century can be divided into five distinct periods and illuminate the re-moralization and moral polarization of the last three decades.