Examining the performance of the chi-square difference test when the unrestricted model is slightly misspecified.

Structural equation models are used to model the relationships between latent constructs and observable behaviors such as survey responses. Researchers are often interested in testing nested models to determine whether additional constraints that create a more parsimonious model are also supported by the data. A popular statistical tool for nested model comparison is the chi-square difference test. However, there is some evidence that this test performs suboptimally when the unrestricted model is misspecified. In this paper, we examine the type I error rate of the difference test within the context of single-group confirmatory factor analyses when the less restricted model is misspecified but the constraints imposed by the restricted model are correct. Using empirical simulations and analytic approximations, we find that the chi-square difference test is robust to many but not all forms of realistically sized misspecification in the unrestricted model.

How Can People Become Happier? A Systematic Review of Preregistered Experiments.

Can happiness be reliably increased? Thousands of studies speak to this question. However, many of them were conducted during a period in which researchers commonly "p-hacked," creating uncertainty about how many discoveries might be false positives. To prevent p-hacking, happiness researchers increasingly preregister their studies, committing to analysis plans before analyzing data. We conducted a systematic literature search to identify preregistered experiments testing strategies for increasing happiness. We found surprisingly little support for many widely recommended strategies (e.g., performing random acts of kindness). However, our review suggests that other strategies-such as being more sociable-may reliably promote happiness. We also found strong evidence that governments and organizations can improve happiness by providing underprivileged individuals with financial support. We conclude that happiness research stands on the brink of an exciting new era, in which modern best practices will be applied to develop theoretically grounded strategies that can produce lasting gains in life satisfaction.

A systematic review of the strength of evidence for the most commonly recommended happiness strategies in mainstream media.

We conducted a systematic review of the evidence underlying some of the most widely recommended strategies for increasing happiness. By coding media articles on happiness, we first identified the five most commonly recommended strategies: expressing gratitude, enhancing sociability, exercising, practising mindfulness/meditation and increasing nature exposure. Next, we conducted a systematic search of the published scientific literature. We identified well-powered, pre-registered experiments testing the effects of these strategies on any aspect of subjective wellbeing (that is, positive affect, negative affect and life satisfaction) in non-clinical samples. A total of 57 studies were included. Our review suggests that a strong scientific foundation is lacking for some of the most commonly recommended happiness strategies. As the effectiveness of these strategies remains an open question, there is an urgent need for well-powered, pre-registered studies investigating strategies for promoting happiness.

Dimensionality, Item Response Theory, Effect Size Attenuation, and Test Bias Analyses of the Self-Importance of Moral Identity Scale (SIMIS).

The extent to which morality and being a moral person are important to one's identity is most commonly assessed using Aquino and Reed's (2002) Self-Importance of Moral Identity Scale (SIMIS). This study provided detailed psychometric examinations of the structure and discrimination levels of the SIMIS in a large (N = 2108) and heterogeneous sample. Results indicated that the SIMIS is clearly 2-dimensional, as expected. The Internalization and Symbolization subscales provided sufficient, and sometimes high levels of test information across the latent trait continuums. There were no redundant items and no bias based on gender. The most notable, albeit minor, shortcomings were that there are too many response options and that test information (discrimination power) was diminished at high levels of the Internalization latent trait continuum, apparently due to skewness. The fluctuating levels of measurement precision resulted in slightly greater attenuations in effect sizes for Internalization than for Symbolization across data for 31 other measures. The present findings from a large dataset and a variety of modern, revealing statistical methods provided relatively consistent, favorable findings for the measure.

Changes in social connection during COVID-19 social distancing: It's not (household) size that matters, it's who you're with.

To slow the transmission of COVID-19, countries around the world have implemented social distancing and stay-at-home policies-potentially leading people to rely more on household members for their sense of closeness and belonging. To understand the conditions under which people felt the most connected, we examined whether changes in overall feelings of social connection varied by household size and composition. In two pre-registered studies, undergraduates in Canada (NStudy 1 = 548) and adults primarily from the U.S. and U.K. (NStudy 2 = 336) reported their perceived social connection once before and once during the pandemic. In both studies, living with a partner robustly and uniquely buffered shifts in social connection during the first phases of the pandemic (ßStudy 1 = .22, ßStudy 2 = .16). In contrast, neither household size nor other aspects of household composition predicted changes in connection. We discuss implications for future social distancing policies that aim to balance physical health with psychological health.