Metaverses may present innovative channels for business and finance, education, and workplaces. Drawing from the Diffusion of Innovation Theory and the Unified Theory of Acceptance and Use of Technology (UTAUT) as well as the literature on digital equality, this research attempts to unravel the dynamics of digital equality and trust in AI-empowered metaverses for various industry sectors. Three cross-sectional surveys (NTotal = 1086) examined US Internet users' intention to adopt metaverses for business, education, and workplaces. Structural equation models were estimated using Mplus 8.8. Study 1 indicates dynamic relationships among digital equality (commerce dimension), blockchain transparency, privacy concerns, and adoption intention. Study 2 shows dynamic associations among digital equality (educational, social, and political dimensions), digital adaptability, loneliness, and adoption intention. Study 3 demonstrates dynamic interconnections among digital equality (labor, government, and health dimensions), digital adaptability, identity threat, and adoption intention. Across three datasets, trust mediates the relationship between digital equality and adoption intention. Theoretical contributions to the emerging literature on decentralized finance (DeFi), AI-driven digital transformation, and AI-VR-convergence are discussed. DeFi businesses, enterprises, policy makers, educators, professional training providers, and workforce developers need to consider third-level digital (in)equality and digital adaptability in developing equitable, sustainable, and inclusive user experience (UX) in AI-empowered metaverses.

BACKGROUND:The conventional clinical approach to characterising traumatic brain injuries (TBIs) as mild, moderate, or severe using the Glasgow Coma Scale (GCS) total score has well-known limitations, prompting calls for more sophisticated strategies. METHODS:We used item response theory (IRT) to develop a new method for quantifying TBI severity using 24 clinical, head computed tomography, and blood-based biomarker variables familiar to clinicians and researchers. IRT uses individuals' response patterns across indicators to estimate relationships between the indicators and a latent continuum of TBI severity. Model parameters were used to assign severity scores in two large cohorts, and associations with traditional GCS categories and 6-month functional outcomes (Glasgow Outcome Scale-Extended [GOSE]) were tested with correlational and logistic regression analyses. FINDINGS:In the prospective Transforming Research and Clinical Knowledge in TBI (TRACK-TBI) cohort (N = 2545), modelling showed the 24 indicators index a common latent continuum of TBI severity. IRT enabled us to identify the relative contribution of these features to estimate an individual's TBI severity. Finally, within both the TRACK-TBI derivation sample and an external validation sample (Collaborative European NeuroTrauma Effectiveness Research in TBI [CENTER-TBI]), TBI severity scores generated using this novel IRT-based method incrementally predicted functional (GOSE) outcome better than classic clinical (mild, moderate, severe) or International Mission for Prognosis and Analysis of Clinical Trials in TBI (IMPACT) classification methods. INTERPRETATION:Our findings directly inform ongoing international efforts to refine and deploy new pragmatic, empirically-supported strategies for characterising TBI, while illustrating a strategy that may be useful to improve staging systems for other diseases. FUNDING:This secondary analysis project was funded by the U.S. National Institute of Neurological Disorders and Stroke (Grant No. R01 NS110856).

Argumentation is a critical genre of writing that elementary school students are expected to develop, but little is known about how different domains of language contribute to argumentative writing. To explore this, we identified two domains of language: linguistic knowledge (lexical, morphological, and syntactic skills) and linguistic awareness (ability to identify and manipulate discourse- and text-level features). We worked with 119 fourth and fifth grade Spanish- and Portuguese-English bilingual students in the Northeast and Mid-Atlantic regions of the United States. We asked whether students’ linguistic knowledge served as a direct predictor of argumentative writing, or as an indirect predictor of argumentative writing, mediated by linguistic awareness. We explored this question with two writing outcomes: students’ argumentation and counter-argumentation. Controlling for orthographic knowledge, essay length, and English learner status, structural equation modeling revealed that students’ linguistic knowledge predicted their argumentative writing indirectly through linguistic awareness, but not directly. Neither the direct nor indirect effects structural model predicted students’ counter-argumentation. Our results extend theory on school-related writing tasks by differentiating between linguistic knowledge and linguistic awareness in understanding bilingual students’ written argumentation, with implications for instruction.

Drawing from the terror management theory (TMT) and evolutionary perspectives of Life-History Strategy, a between-subject online experiment examined the interaction effects of pre-existing death anxiety, fear-inducing media content (coronavirus threat vs. gun violence threat vs. low threat mental disorder), and intrasexual competition for mates on online dating intentions and social distancing intentions during the COVID-19 pandemic. Results indicate the interaction effects of participants' pre-experimental death anxiety and different types of fear-inducing media content on perceived fear and intention to use online dating websites/apps as well as the interaction effects of pre-experimental intrasexual competitiveness and fear-inducing media content on social distancing intention in the context of online dating. Theoretical contributions to the terror management literature and practical implications for the online dating industry are discussed.

The present article is an attempt to offer insights into interconnections among consumer personality, individual difference factors, Instagram usage behavior, and luxury fashion brand attitude in contemporary Web 2.0 technological environments. To this end, the study particularly focused on Instagram, a highly visual social media platform, mostly used in the form of a mobile app. Instagram fits the purpose of consumers’ vanity. Personality mechanisms, known to produce effects of personality traits on digital technology usage behaviors, that shape consumer behavior in the context of Instagram usage and luxury fashion brand consumption were examined. A cross-sectional survey was conducted among actual Instagram users recruited from M-Turk Prime Panel. A series of structural equation models (SEM) were estimated using Mplus 8. Two structural equation models are estimated: one with objective Instagram usage frequency, and the other with subjective Instagram usage intensity. Results show dynamic associations among Instagram users’ personality variables, individual difference factors, Instagram usage frequency/intensity, and luxury brand involvement. In light of the power of Instagram in luxury fashion branding, the current study proposes a variety of personality mechanisms and individual difference factors (vanity, materialism, social comparison orientation, obsessive-compulsive/impulsive buying tendency, and market mavenism) that shape Instagram users’ attitude toward and involvement with luxury fashion brands in Web 2.0 social commerce.

BACKGROUND:Neuropsychiatric symptoms are common after traumatic brain injury (TBI) and often resolve within 3 months post-injury. However, the degree to which individual patients follow this course is unknown. We characterized trajectories of neuropsychiatric symptoms over 12 months post-TBI. We hypothesized that a substantial proportion of individuals would display trajectories distinct from the group-average course, with some exhibiting less favorable courses. METHODS:Participants were level 1 trauma center patients with TBI (n = 1943), orthopedic trauma controls (n = 257), and non-injured friend controls (n = 300). Trajectories of six symptom dimensions (Depression, Anxiety, Fear, Sleep, Physical, and Pain) were identified using growth mixture modeling from 2 weeks to 12 months post-injury. RESULTS:Depression, Anxiety, Fear, and Physical symptoms displayed three trajectories: Stable-Low (86.2-88.6%), Worsening (5.6-10.9%), and Improving (2.6-6.4%). Among symptomatic trajectories (Worsening, Improving), lower-severity TBI was associated with higher prevalence of elevated symptoms at 2 weeks that steadily resolved over 12 months compared to all other groups, whereas higher-severity TBI was associated with higher prevalence of symptoms that gradually worsened from 3-12 months. Sleep and Pain displayed more variable recovery courses, and the most common trajectory entailed an average level of problems that remained stable over time (Stable-Average; 46.7-82.6%). Symptomatic Sleep and Pain trajectories (Stable-Average, Improving) were more common in traumatically injured groups. CONCLUSIONS:Findings illustrate the nature and rates of distinct neuropsychiatric symptom trajectories and their relationship to traumatic injuries. Providers may use these results as a referent for gauging typical v. atypical recovery in the first 12 months post-injury.

Digital platforms present consumers with contrasting visual narratives, from images of opulence to depictions of poverty. This study delves into the strategic implications of such dichotomous exposures, anchored in Social Comparison Theory. Three experiments (& sum; N = 1665) investigated how portrayals of affluence and deprivation influence audience behaviors, specifically egoistic luxury spending versus altruistic charitable giving. Experiment 1a employed a 2 (exposure to photos of poverty versus affluence) x 2 (luxury spending versus charitable giving scenario as the within-subjects factor) mixed factorial design. Experiment 1b employed a 2 (poverty versus affluence) x 2 (luxury spending versus charitable giving) between-subjects factorial design. Experiment 2 employed a 3 (poverty versus affluence versus neutral photos) x 2 (anonymized versus publicized donation) between-subjects factorial design to further examine the interaction effects of social comparison direction and donation mode. Empirical findings highlight that downward social comparison (exposure to poverty) can amplify charitable inclinations, while upward comparison (exposure to affluence) can enhance conspicuous consumption. Individual difference factors such as materialism, need for status, social comparison orientation, and greed play pivotal roles in moderating these effects. This research contributes to the understanding of digital portrayal influences on consumers' spending behavior, offering both theoretical insights and practical implications for strategic communication.

Background Our goal in this report was to quantify the degree to which opioid prescription rates and socioeconomic correlates of income inequality predicted overdose deaths in the 1055 U.S. Midwest counties. The study follows up a state-level analysis which reported that opioid prescription rates, social capital and unemployment explained much of the variance in opioid overdose death rates (Heyman, McVicar, & Brownell, 2019). Methods We created a data set that included drug overdose death rates, opioid prescription rates, and correlates of income inequality. Given that the variables of interest varied at the state and county level, multilevel regression was our statistical approach. Results From 2006 to 2021, Midwest overdose drug deaths increased according to an exponential equation that closely approximated the equation that describes the increases in overdose deaths for the entire U.S. from 1978 to 2016 (e.g., Jalal et al., 2018). Retail opioid prescription sales increased from 2006 to 2012, but then declined so that by 2017 they were lower than in 2006. The regression analyses revealed that intergenerational income mobility was the strongest predictor of overdose deaths. The other consistently statistically significant predictors were opioid prescription rates, social capital, and unemployment rates. Together these predictors, plus pupil teacher ratios, single parent families, and attending college accounted for approximately 47 % of the variance in overdose death rates each year. In keeping with the decline in opioid prescription rates, the explanatory power of opioid prescription rates weakened over the course of the study. Conclusions Overdose deaths increased at a constant exponential rate for the years that it was possible to apply our regression model. This occurred even though access to legal opioids decreased. What remained invariant was the predictive strength of intergenerational income mobility; each year it was the predictor that explained the most variance in overdose deaths.

Research investigating effects of music instruction on executive functioning (EF) has yielded mixed results, relying only on a small and inadequate number of true randomized and controlled experiments (Dege & Frischen, 2022). We report here an experimental study of the effects of 2 years of school-based orchestral music training on young children's EF, self-perception, and school-liking, all of which showed no effect. Children were randomly chosen either to participate in one of three intensive, high-dosage, El Sistema-inspired school-based orchestral music programs or to be part of a control group receiving standard, general music education (which normally does not include mastering a musical instrument) as part of their regular school day. Children were tested at baseline (end of kindergarten), after 1 year, and after 2 years (end of second grade) on four measures of EF, two measures of self-perception, and one measure of school-liking. All students were randomly assigned to the music group or a control group, and baseline differences between the groups were not statistically significant. Despite the intensity of the orchestral music program, no significant effects were found at any timepoint for any measures. We stress the importance of publishing null findings in light of psychology's replication crisis, the common misrepresentation of correlational findings as causal, and the difficulties that exist in demonstrating far transfer effects. We conclude by cautioning against the justification of music education on the basis of extramusical outcomes, and instead suggest a focus on the intrinsic value of music education itself.

Diversity, equity, and inclusion sciences were invigorated by Plaut's (2010) landmark publication "Diversity science: Why and how difference makes a difference." As this field has expanded over the last decade, it is timely to reflect on its current state and future directions. The goal of this special issue is to bring together a collection of articles that advance innovative theory and methods for the next generation of diversity, equity, and inclusion sciences. The articles in this special issue cover cutting-edge themes, such as critical research methods for liberation, healing, and reconciliation; advancing intersectional theory and methods; innovative theory and methods on individual-social dynamics; promoting equity and advancing research on culture, ethnicity, and race; and new approaches to measuring and overcoming racism. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

In 2017, the Acting U. S. Secretary of Health and Human Services declared the “opioid crisis” a nation-wide health emergency. However, the crisis’s geography was not nation-wide. Many counties and towns had no overdose deaths, whereas others were home to hundreds. According to many influential research reports and news stories, geographic variation in overdose deaths was due to geographic variation in opioid prescription rates and/or geographic variation in socioeconomic factors, such as unemployment. Our goal was to test the degree to which prescription rates and socioeconomic correlates of income inequality predicted overdose deaths in the 1055 U.S. Midwest (“Heartland”) counties over the years 2006 to 2020. We used multilevel regression models to gauge the predictive strength of overdose rates and six socioeconomic measures that are correlated with income inequality. There were significant state-level and county-level differences. Intergenerational income mobility was the strongest predictor of overdose deaths, with regression coefficients that averaged about twice as large as the coefficients for opioid prescription rates. Every year, counties with greater upward intergenerational income mobility had lower overdose death rates. Social capital had the second largest regression coefficients, albeit by a small margin. Counties are the smallest demographic unit for which drug overdose rates are available; the results of this study link growing income inequality and drug overdose deaths at the county level. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study did not receive any funding ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Data were obtained from widely used, publicly available websites, primarily the CDC and Harvard University (Opportunity Insights). The sources, with their links, are listed in the body of the paper and in reference list. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes 1. [cdc.gov][1] [Internet]. Atlanta (GA): CDC Wonder: Multiple Cause of Death, 19992020 Request; [cited 2023 June 27]. Available from: 2. [usdoj.gov][2] [Internet]. Arlington (VA): United States Department of Justice Drug Enforcement Administration; [cited 2023 June 27]. Available from: 18. [stacks.cdc.gov][3] [Internet]. Atlanta (GA): National Center for Health Statistics; [cited 2023 Jun 28]. Available from: 27. Rossen LM, Bastian B, Warner M, Khan D, Chong Y. County-level drug overdose mortality: United States, 20032020 [Data file and Map]. National Center for Health Statistics: Hyattsville(MD); 2022. [cited 2023 Jun 28]. Available from: 28. CDC Injury Center [Internet]. US: The Center; 2006-2020 [cited 2023 Jun 28]. Opioid Dispensing Rate Maps; [about 5 screens]. Available from: 30. [opportunityinsights.org][4] [Internet]. Cambridge: Harvard University; c2023 [cited 2023 Jun 28]. Available from: [https://www.deadiversion.usdoj.gov/arcos/retail\_drug\_summary][5] [1]: http://cdc.gov [2]: http://usdoj.gov [3]: http://stacks.cdc.gov [4]: http://opportunityinsights.org [5]: https://www.deadiversion.usdoj.gov/arcos/retail_drug_summary

The brain is composed of networks of interacting brain regions that support higher-order cognition. Among these, a core network of regions has been associated with recollection and other forms of episodic construction. Past research has focused largely on the roles of individual brain regions in recollection or on their mutual engagement as part of an integrated network. However, the relationship between these region- and network-level contributions remains poorly understood. Here, we applied multilevel structural equation modeling to examine the functional organization of the posterior medial (PM) network and its relationship to episodic memory outcomes. We evaluated two aspects of functional heterogeneity in the PM network: first, the organization of individual regions into subnetworks, and second, the presence of regionally specific contributions while accounting for network-level effects. Our results suggest that the PM network is composed of ventral and dorsal subnetworks, with the ventral subnetwork making a unique contribution to recollection, especially to recollection of spatial information, and that memory-related activity in individual regions is well accounted for by these network-level effects. These findings highlight the importance of considering the functions of individual brain regions within the context of their affiliated networks.

Instagram not only offers an arena for the fulfillment of basic human desires but also cultivates new types of multifaceted desires and consumptions in Web 2.0 environments. This study aims to examine a wide variety of dispositional, psychological, and attitudinal predictors of Instagram consumption and selfie-and-groupfie cultures. Three cross-sectional surveys (Study 1 (N = 108); Study 2 (N = 140); Study 3 (N = 557)) were conducted, and empirical data were analyzed using structural equation modeling (SEM) with Mplus 8.0. Study 1 shows associations among appearance-related self-confidence, appearance-related actual–ideal self-discrepancy, materialism, and Instagram consumption. Study 2 confirms relationships among weight status perception, self-esteem, eating disorder, malicious envy, and Instagram consumption intensity. Study 3 further demonstrates dynamic associations among eating disorders, perceived mate value, narcissistic grandiosity, envy, social comparison, intrasexual competition for mates, and frequency of posting selfies/groupfies on Instagram. Theoretical contributions to the psychosocial and human aspects of the Web 2.0 digital culture, managerial implications for online dating cultures, and practical implications for consumption markets including social media-based health communication, cultural communication, and marketing communication are discussed.

AbstractWhy do people give and help others in face of their own mortality salience? The existential struggle with the awareness of death impacts the gamut of human cognition, emotion, and behavior. This multi‐method research (∑N = 1,219) explains the psychosocial impact of COVID‐19‐related mortality salience on altruism. Drawing from terror management theory, two studies tested death‐thought accessibility, mortality salience, and anxiety buffer hypotheses. Study 1 (cross‐sectional survey), using structural equation modeling, confirms death anxiety and fear are predictors of powerlessness and materialism which, in turn, predict charitable donations. Study 2 (between‐subjects experiment) confirms the causal effects of COVID‐19‐induced mortality salience on altruism. Controlling income and socioeconomic status, people in the mortality salience treatment condition indicate greater monetary donations ($), ratio of prosocial (altruistic) to proself (egocentric) spending (%), donation of time (hour), monetary valuation of time (hourly rate = $/hour), and economic value of donated time (hourly rate*hour) than the controls. These effects are mediated by powerlessness. Moderating effects of relevant individual difference factors are significant: the greedier, more selfish, narcissistic, materialistic, and system‐justifying the donor is, the higher monetary donations, volunteer time, and perceived value of donated time are, only when the COVID‐19‐induced mortality is made salient but not in the controls. Environmental and dispositional factors jointly influence vulnerability to mortality salience. The paradox of egocentrism and altruism, as an evolutionarily adaptive protective buffer against existential insecurity for social and cultural animals, can help revitalize resilience, thus shedding some lights on the sociopsychological mechanism of consumers' subjective well‐being. Implications for consumer affairs, social marketers, and policymakers are discussed.

PurposeSocial media campaigns by fashion brands typically rely on two types of accounts: official brands' accounts and social media influencers' accounts. The current study investigates relevant mechanisms that explain the effectiveness of Instagram posts contingent upon their account types (commercial brand's Instagram account versus influencer's Instagram account) and content types (the absence versus presence of human figures in the posted contents).Design/methodology/approachConducting an online experiment (N Females = 195), it was tested if parasocial interaction (PSI) and feelings of social presence moderate the effects of Instagram accounts' promotional posts on consumers' perceived trustworthiness of the endorsed fashion brand. The experiment employed a 2 (Type of Instagram posts: product-only posts versus product posts with a person content) × 2 (Type of Instagram account: a fashion-brand account versus a a fashion-influencer account) between-subjects factorial design.FindingsResults demonstrate three-way interaction effects among the type of the Instagram account, the type of Instagram posts and PSI/social presence on the perceived trustworthiness of a brand. When the content is coming from a fashion-influencer account, there is no difference between product posts with a person and product-only posts conditions with regard to the positive relationship between PSI/social presence and trustworthiness. In contrast, when the source is a fashion-brand account on Instagram, the positive relationship between PSI/social presence and trustworthiness is stronger for product posts with a person. These findings suggest that Instagram posts that are promoted by fashion influencers would have similar effects of PSI and social presence, even if they do not appear themselves in the branded content.Originality/valueThis research contributes to our understanding of the effective antecedents of trustworthiness in social media-based fashion marketing and fashion brand management. Instagram account types and content types influence the extent to which social media communication allows for the formation of emotional ties with and positive evaluation of the fashion brand.

Companies increasingly leverage Instagram as a channel for brand management, consumer services, and social commerce. This study addresses the dynamics of interaction among brand-related user-generated contents (UGC) posted on Instagram, social media-based brand communication with Instagram celebrities (parasocial interaction [PSI] and envy), and consumers' characteristics (social comparison tendency, compulsive buying tendency, and materialistic envy). Three between-subjects experiments (Experiment 1: N = 121; Experiment 2: N = 106; Experiment 3: N = 377) were conducted to test the effects of Instagram influencers and their branded-UGC on consumer behavior outcomes. Experiment 1 employed a 3 (branded content type [Instagram influencer's photo type]: selfies vs. photos taken by others vs. group photos) x 2 (gender: female vs. male) factorial design. Experiment 2 employed a 2 (content generator type: Instagram celebrity vs. mainstream celebrity) x 2 (gender: female vs. male) factorial design. Experiment 3 deployed a 2 (branded content type: photos listing products vs. photos showing models) x 2 (content generator type: commercial brand [corporate] vs. Instagram celebrity [human]) factorial design. Experiment 1 indicates Instagram influencers' photo types and gender moderate the effects of envy toward and PSI with them on consumers' intention to buy the products Instagram influencers are wearing. Experiment 2 shows content generator types and gender moderate the effects of envy and PSI on source trustworthiness perception. Experiment 3 demonstrates branded content types and content generator types moderate the effects of consumers' physical appearance social comparison tendency, compulsive buying tendency, and materialistic envy on brand trust. This study makes theoretical contributions to the literature on retailing and consumer services as well as provides managerial implications for Instafamous-based influencer marketing and social commerce in Web 2.0 environments.

Purpose Luxury fashion brands harness the power of Instagram and fashionistas for strategic brand management. This study aims to test interaction effects among luxury brand posts’ Instagram source type (brand versus fashionista), visual image type (product-centric versus consumer-centric) and consumers’ characteristics (vanity, opinion leadership and fashion consciousness) on brand recognition and trust. Design/methodology/approach A quantitative 2 (source type: brand versus fashionista) × 2 (branded visual image type: product-centric luxury versus consumer-centric luxury) between-subjects online experiment (N males = 195 and N females = 182) was conducted by recruiting participants from MTurk. Findings Logistic regression analyses indicated two-way interaction effects between sources and visual images on brand recognition. Brand recognition was higher for product-centric images when the source was the fashionista, whereas brand recognition was equivalent regardless of the image type when the source was the brand. Logistic regression and multiple regression analyses revealed the moderating effects of sources and visual images on the association between consumer traits and branding outcomes. Practical implications Meticulously choosing effective methods of showcasing branded content and persuasive luxury visual image strategies via Instagram is more important for fashionistas than for established brands in increasing brand recognition. Instagram fashionistas are more effective in increasing females’ brand trust through delivering product-centric visual images when targeting women with high vanity, opinion leadership and fashion consciousness. Brands as the Instagram profile source are more persuasive in increasing males’ brand trust through delivering product-centric visual images when targeting men with high vanity. Originality/value This experiment provides theoretical discussions and empirical findings about social media influencer marketing and managerial implications for Instagram-based luxury branding. This research revolves around the overarching theme of the interactive effects of multifaceted branded contents and market segments in social media influencer marketing environments.

Instagram selfies and groupies symbolize social media users’ public display of narcissism. From an evolutionary psychological perspective on the renovated hierarchy of fundamental human motives and needs, this study examined the interaction effects of Instagram photo types (selfies, group selfies, long-shot photos taken by others, and neutral photos) and Instagram peer viewers’ individual difference factors (intrasexual competition [ISC] for mates, need for popularity [NfP], loneliness, and need to belong [NtB]) on intersexual attraction. A randomized between-subjects experiment (N = 110) was executed to see how the interaction affects the intention to date the target opposite-sex person. Multiple regression analyses confirm the moderating effects of ISC for mates, NfP, loneliness, and NtB on dating desire, among heterosexual/bisexual males exposed to female Instagram photos. Viewer characteristics moderate the influence of the potential mate’s photo types on perception and dating desirability. This study makes theoretical contributions to the literature on evolutionary psychology of narcissism and the renovated pyramid of primary needs. With regard to practical implications for online dating apps/social networking sites, neutral photos are more effective to appeal to men who feel lonely and have higher need for belonging and popularity, whereas group selfies are more appealing to men who have lower ISC for mate, NtB, and NfP.

Purpose In light of Facebook-based viral marketing and social commerce, the purpose of this paper is to test the moderating role of social identification with the Facebook profile owner (celebrity as aspirational reference group vs ingroup member (college student, same school) vs outgroup member (college student, different school)) in Facebook-based fashion brand marketing and management. Design/methodology/approach A randomized between-subjects experiment (celebrity's Facebook profile vs ingroup member's Facebook profile vs outgroup member's Facebook profile vs control condition, n=73) was conducted. The sample was composed of college students recruited from a subject pool in a US university. Findings Results of multiple regression analyses indicate that social identification with the Facebook profile owner and ingroup vs outgroup perception moderate the influence of consumers' materialism, fashion involvement and opinion leadership on interpersonal attraction to the celebrity, wishful identification with the celebrity, emotional quotient, involvement with the ads, advertising believability and willingness to buy the advertised fashion products. Furthermore, the results of structural equation modeling analyses show that source credibility perception (both the celebrity who endorses her own brand and the Facebook profile owner) mediates the relationship between experimental conditions (celebrity as aspirational outgroup vs same school student as an ingroup member vs different school student as an outgroup member) and the outcome variables (interpersonal attraction to the celebrity, involvement with ads, and advertising believability) in viral marketing leveraging a social media platform. Originality/value This study makes several theoretical contributions to consumer psychology and provides managerial implications for Facebook-based fashion marketing and fashion brand management.

PurposeThe purpose of this paper is to test the effects of two types of celebrities (Instagram celebrity vs traditional celebrity) on source trustworthiness, brand attitude, envy and social presence. The proposed theoretical model consists of the celebrity type as the independent variable, social presence as the mediator and self-discrepancy as the moderator.Design/methodology/approachA randomized two-group comparison (Instagram celebrity vs traditional celebrity) between-subjects experiment (n=104) was conducted.FindingsThe results indicate that consumers exposed to Instagram celebrity’s brand posts perceive the source to be more trustworthy, show more positive attitude toward the endorsed brand, feel stronger social presence and feel more envious of the source than those consumers exposed to traditional celebrity’s brand posts. Structural equation modeling (Mplus 8.0) and bootstrap confidence intervals indicate that social presence mediates the causal effects of celebrity type on trustworthiness, brand attitude and envy. Multiple regression analyses reveal the moderating effects of appearance-related actual–ideal self-discrepancy.Practical implicationsUltimately, managerial implications for social media marketing and Instagram influencer-based branding are provided. From the perspective of marketing planning, the findings speak to the power of influencer marketing as an effective branding strategy.Originality/valueThe paper discusses theoretical implications for the marketing literature on celebrity endorsements.