Power to Detect What? Considerations for Planning and Evaluating Sample Size.

ACADEMIC ABSTRACT: In the wake of the replication crisis, social and personality psychologists have increased attention to power analysis and the adequacy of sample sizes. In this article, we analyze current controversies in this area, including choosing effect sizes, why and whether power analyses should be conducted on already-collected data, how to mitigate the negative effects of sample size criteria on specific kinds of research, and which power criterion to use. For novel research questions, we advocate that researchers base sample sizes on effects that are likely to be cost-effective for other people to implement (in applied settings) or to study (in basic research settings), given the limitations of interest-based minimums or field-wide effect sizes. We discuss two alternatives to power analysis, precision analysis and sequential analysis, and end with recommendations for improving the practices of researchers, reviewers, and journal editors in social-personality psychology. PUBLIC ABSTRACT: Recently, social-personality psychology has been criticized for basing some of its conclusions on studies with low numbers of participants. As a result, power analysis, a mathematical way to ensure that a study has enough participants to reliably "detect" a given size of psychological effect, has become popular. This article describes power analysis and discusses some controversies about it, including how researchers should derive assumptions about effect size, and how the requirements of power analysis can be applied without harming research on hard-to-reach and marginalized communities. For novel research questions, we advocate that researchers base sample sizes on effects that are likely to be cost-effective for other people to implement (in applied settings) or to study (in basic research settings). We discuss two alternatives to power analysis, precision analysis and sequential analysis, and end with recommendations for improving the practices of researchers, reviewers, and journal editors in social-personality psychology.

Psychometric Evaluation of Single-Item Relationship Satisfaction, Love, Conflict, and Commitment Measures.

Issues in applied survey research, including minimizing respondent burden and ensuring measures' brevity for smartphone administration, have intensified efforts to create short measures. We conducted two studies on the psychometric properties of single-item satisfaction, love, conflict, and commitment measures. Study 1 was longitudinal, surveying college-age dating couples at three monthly waves (n =121, 84, and 68 couples at the respective waves). Partners completed single- and multi-item measures of the four constructs, along with other variables, to examine test-retest reliability and convergent, concurrent, and predictive validity. Single-item measures of satisfaction, love, and commitment exhibited impressive psychometric qualities, but our single-item conflict measure performed somewhat less strongly. Study 2, a cross-sectional online survey (n = 280), showed strong convergent validity of the single-item measures, including that of conflict.

Long-Term Psychological Health among Individuals Pursuing Emerging Adulthood-Type Pathways in the 1950s and 1960s.

We analyzed data from the Wisconsin Longitudinal Study (N = 6390) to investigate how common an emerging adulthood-type lifestyle (e.g., delayed marriage and childbearing, pursuit of higher education) was in the late 1950s and early 1960s, and what the long-term psychological-health correlates were of such a lifestyle. Cluster analyses of marital, childbearing, educational, and occupational variables from 1957 (high school graduation) to 1964 generated six clusters that we labeled: fast-starters (early marriage and childbearing, little education beyond high school, virtually all employed), very-educated/partnered (mean educational attainment well into graduate school and among the earliest to get married), moderately educated/family oriented (mean years of education somewhat shy of a bachelor's degree, early marriage and childbearing), educated singles (late marriage and childbearing, if at all, averaging a bachelor's degree; most prototypical of emerging adulthood), work/military first (little education past high school, late marriage and childbearing), and military/professional aspiration (envisioning career requiring college education and pursuing one). The clusters were then compared on health and well-being measures from 1992-93 and 2003-05, controlling for family-of-origin socioeconomic status. In general, individuals whose life pursuits combined higher education, professional career aspirations, and marriage exhibited the best long-term psychological health. Results are discussed in terms of historical conditions when these individuals transitioned to adulthood.

Do episodic self- and partner-uncertainty mediate the association between attachment orientations and emotional responses to relationship-threatening events in dating couples?

This study examined relational-uncertainty perceptions (a form of cognitive appraisal) to investigate how partners in 272 heterosexual couples responded emotionally to a relationship-challenging event. Participants rated themselves on attachment anxiety and avoidance. Then, after listing a challenging event, they rated how uncertain it made them about their own and their partner's continued involvement in the relationship. Participants also rated how angry and fearful the event made them. An Actor-Partner Interdependence Model yielded three sets of results. First, actor effects from insecure attachment orientations to episodic relational uncertainty emerged. Second, proposed mediation between attachment orientations and emotional reactions by uncertainty was partially supported (perceived partner-uncertainty partially mediated the positive association of anxious attachment and fear, and self-uncertainty partially mediated the positive relation between avoidant attachment and anger). Finally, a partner effect was found between one couple member's avoidant attachment and the other's perceived partner uncertainty. Men and women exhibited similar findings.

In-hospital Breastfeeding and Intention to Return to Work Influence Mothers' Breastfeeding Intentions.

BACKGROUND: Research continues to demonstrate that formula feeding is associated with numerous long-term negative outcomes for a mother and her infant. However, many women cease breastfeeding sooner than intended and recommended. Breastfeeding has been found to be related to demographics, maternal mood, and returning to work outside the home. OBJECTIVES: This study aimed to shed light on the woman's perception of the effect of working on intended breastfeeding duration. This study used intentions to return to work and in-hospital breastfeeding to predict breastfeeding intentions. METHODS: Women (N = 160) were surveyed during the first 48 hours postdelivery of healthy, full-term infants. Survey instruments included demographics (socioeconomic status, maternal age, education, and marital status), depression, fetal attachment, current exclusive breastfeeding status, as well as breastfeeding and return-to-work intentions for the next year. A path analysis was used to explore relationships and predictors of breastfeeding intentions. RESULTS: The model had a good fit and breastfeeding intentions were predicted by exclusive breastfeeding in the hospital (ß = 0.21, P < .01) and negatively predicted by return to work (ß = -0.18, P < .05). CONCLUSION: Exclusive breastfeeding in the hospital within the first 48 hours postpartum and intention to return to work influence how long a mother intends to breastfeed. Attention to these areas can be provided immediately postpartum to support exclusive breastfeeding and provide informational support on continuing to breastfeed/express milk upon return to work if the mother intends to return to work.

Evaluation of the Psychometric Properties of the Revised Inventory of the Dimensions of Emerging Adulthood (IDEA-R) in a Sample of Continuation High School Students.

It is now presumed that youth do not move directly from adolescence to adulthood, but rather pass through a transitional period, "emerging adulthood." The Revised Inventory of the Dimensions of Emerging Adulthood (IDEA-R) is a self-report instrument developed to examine the attributes of this period. "At-risk" youth appear to enter emerging adulthood developmental tasks at a slightly earlier age than general population youth. In the present study, a 21-item version of the IDEA was administered to a sample of 1676 "at-risk" continuation (alternative) high school students in Southern California. Principal component factor analysis with orthogonal rotation revealed three factors the authors labeled "Identity Exploration," "Experimentation/Possibilities," and "Independence." Overall, the measure demonstrated high internal consistency. Construct validity analyses indicated that the measure was correlated with demographics, risk behaviors, and psychological measures. The authors conclude that the IDEA-R is a useful instrument for measuring emerging adulthood in at-risk populations.

Harnessing the Undiscovered Resource of Student Research Projects.

This article suggests that undergraduate research can help advance the science of psychology. We introduce a hypothetical "question-list paradigm" as a mechanism to do this. Each year, thousands of undergraduate projects are completed as part of the educational experience. Although many of these studies may not contain sufficient contributions for publication, they provide a good test of the replicability of established findings across populations at different institutions and geographic locations. Thus, these projects could meet the needs of recent calls for increased replications of psychological studies while simultaneously benefiting the student researchers, their instructors, and the field in general.

Social networks and college drinking: probing processes of social influence and selection.

This study used a three-wave panel design (N = 119 complete cases for all waves) to test for social influence and selection in the relation of college students' heavy drinking and that of their social networks. Evidence emerged for both social influence and selection, leading the authors to probe more specialized issues related to each. Results regarding social influence revealed, further, that greater presence in the network of individuals that the focal respondent considered "drinking buddies" was predictive of one's own later drinking, controlling for potential confounds. Network demographic characteristics associated with a "risky" (i.e., heavy-drinking) network also were documented. An additional finding, important for selection, was that wave-to-wave change in average network drinking appeared to result primarily from network members with different drinking levels being added to and dropped from the network. Findings are discussed in the context of the recent renaissance in social-network research.

Differences in self-report measures by adolescent sex offender risk group.

Differences in self-reports among three groups of juvenile sex offenders (N = 162) were examined. Risk was defined as the sum of the following static variables based on interviews with juveniles and others and from written records: type of offense (violent or predatory = 1, not = 0), prior sex offense (any = 1, none = 0), history of sexual abuse (self or family = 1, none = 0), history of substance abuse (self or family = 1, none = 0), history of behavior problems (yes = 1, no = 0), and unstable home life (yes = 1, stable = 0). Low-risk (0 to 2 risk factors), medium-risk (3 factors), and high-risk (4 to 6 factors) groups of offenders were formed. Univariate ANCOVAs indicated that the high-risk group reported less family cohesion, more aggression, lower self-esteem, more social discomfort, and more frequent and extreme sexual fantasies. The implications of these findings for differential identification of and interventions with adolescent sex offenders are discussed.

Sexual-moral attitudes, love styles, and mate selection.

Students at a southwestern university were surveyed to test the interrelations of three constructs: sexual-moral attitudes, love styles, and attraction criteria. Following the procedures of the National Health and Social Life Survey, from which the sexual-moral attitude items were obtained, we conducted a cluster analysis to create attitudinal groupings. We obtained four clusters representing various nuances of liberalism and conservatism. When compared on love styles, the clusters differed primarily on ludus and pragma. Not only did some of the liberal clusters differ from some of the conservative ones on love styles, but there were also some differences within liberalism and within conservatism. Cluster differences also emerged on the attraction criteria.

Binge drinking during the first semester of college: continuation and desistance from high school patterns.

Students' first semester on campus may set the stage for their alcohol use/misuse throughout college. The authors surveyed 274 randomly sampled first-semester freshmen at a large southwestern university on their past 2 weeks' binge drinking, their high school binge drinking, and psychosocial factors possibly associated with drinking. They conducted separate analyses among high school nonbinge drinkers (testing for predictors of college binge onset vs continued nonbinge drinking) and high school binge drinkers (testing for predictors of continued binge drinking in college vs desistance from drinking). In both analyses, the variables that predicted college binge drinking largely revolved around gregarious socializing (e.g, partying, having a social network of individuals who drank relatively heavily). Gender was predictive only among high school nonbinge drinkers; women had a higher probability than did men of adopting binge drinking in college.