Student-student relationship and adolescent problematic smartphone use: The mediating role of materialism and the moderating role of narcissism

Journal Pre-proofs Student-student relationship and adolescent problematic smartphone use: The mediating role of materialism and the moderating role of narcissism Mingkun Ouyang, Xiao Cai, Yulong Yin, Pan Zeng, Ye Chen, Xingchao Wang, Xiaochun Xie, Pengcheng Wang PII: DOI: Reference:

S0190-7409(19)31209-5 https://doi.org/10.1016/j.childyouth.2020.104766 CYSR 104766

To appear in:

Children and Youth Services Review

Received Date: Revised Date: Accepted Date:

24 October 2019 10 January 2020 10 January 2020

Please cite this article as: M. Ouyang, X. Cai, Y. Yin, P. Zeng, Y. Chen, X. Wang, X. Xie, P. Wang, Studentstudent relationship and adolescent problematic smartphone use: The mediating role of materialism and the moderating role of narcissism, Children and Youth Services Review (2020), doi: https://doi.org/10.1016/ j.childyouth.2020.104766

This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

© 2020 Elsevier Ltd. All rights reserved.

Running head: Student-student relationship and adolescent problematic smartphone use Student-student relationship and adolescent problematic smartphone use: The mediating role of materialism and the moderating role of narcissism Mingkun Ouyanga,1, Xiao Caia,1, Yulong Yina,1, Pan Zenga, Ye Chenb, Xingchao Wangc , Xiaochun Xied , Pengcheng Wanga,* a. Department of Psychology, Renmin University of China, No. 59 Zhongguancun Street, Haidian District, Beijing 100872, China b. Hebei Dingzhou High School, Dingzhou, Hebei 073000, China c. School of Educational Science, Shanxi University, No. 92 Wucheng Road, Xiaodian District, Taiyuan 030006, China d. School of Psychology & Jilin Provincial Experimental Teaching Demonstration Center of Psychology, Northeast Normal University, Changchun, 130024, China 1. Mingkun Ouyang, Xiao Cai, and Yulong Yin are first authors of equal contribution to this work. * Correspondence concerning this article should be addressed to Pengcheng Wang, Department of Psychology, Renmin University of China, No. 59 Zhongguancun Street, Haidian District, Beijing 100872, China, Email: [email protected]

Student-student relationship and adolescent problematic smartphone use: The mediating role of materialism and the moderating role of narcissism 1

Abstract Although recent studies have documented that student-student relationship (SSR) is associated with adolescents’ problematic smartphone use (PSU), the mediating and moderating mechanisms underlying this association remain largely unexplored. In the present study, we investigated the mediating role of materialism in the association between SSR and adolescents’ PSU as well as the moderating role of narcissism in the direct and indirect pathways between SSR and PSU. Seven hundred and twelve adolescents completed the measures of SSR, PSU, materialism, and narcissism. The results indicated that SSR was negatively associated with PSU, and materialism mediated this association. In addition, narcissism moderated the association between SSR and materialism and the link between materialism and PSU. Specifically, adolescents with high levels of narcissism are less likely to prioritize materialism when they are in poor SSR, while they are more likely to have a higher level of PSU when they are high in materialism. Altogether, these findings highlight the important roles of materialism and narcissism in the association between SSR and adolescents’ PSU. Keywords: student-student relationship, problematic smartphone use, materialism, narcissism, adolescents

2

1. Introduction Smartphones have become an indispensable part in people’s lives. Given their advantages of portability, availability, and multifunctionality, smartphones are attracting more and more adolescents to use them for browsing the internet, playing games, accessing shopping, and social media. For example, in some developed countries such as America (Anderson & Jiang, 2018), Switzerland (Willemse, Waller, & Süss, 2014), and South Korea (Korean Information Society Development Institute, 2018), over 90% adolescents reported using a smartphone. Meanwhile, in some developing countries such as China, more than 137 million adolescents reported having access to a smartphone (CNNIC, 2018). Problematic smartphone use (PSU) is defined as a state in which people are immersed in smartphone use and cannot control themselves (Demirci, Akgönül, & Akpinar, 2015; Pearson & Hussain, 2015). As a part of cyber problematic use, PSU usually encompasses a variety of online problematic behaviors such as social media use, mobile games, gambling, and sexting (Billieux, 2012; Hwang & Park, 2017). In the present study, we conceptualized PSU as a broad concept that may cover various problematic behaviors through smartphones, given that these behaviors, to some extent and in some aspects, share psychological mechanisms (e.g., poor self-control and impulsivity) (Billieux, 2012). PSU is related to a series of negative outcomes. For example, adolescents with high levels of PSU tend to suffer from severe mental health problems (e.g., depression, anxiety, and low self-esteem) (Demirci et al., 2015; Elhai, Dvorak, Levine, & Hall, 2017), poor academic performance (Lepp, Barkley, & Karpinski, 2014), and low-quality social relationships (Elhai et al., 2017; Wang et al., 2017). Given these detrimental consequences, it is of theoretical and practical importance to investigate the factors that influence adolescents’ PSU. Student-student relationship (SSR) is a major component of peer relationship and refers to the degree of social support and care from schoolmates (Wang, Wang, & Lei, 2019). Theorists and researchers have emphasized the role of peer relationship in the personal and social development of adolescents, because they are in the stage of detaching themselves from parents and attaching themselves to peers to form an identity (Bukowski, Motzoi, & Meyer, 2008). According to the social control theory, individuals’ bond to others or groups could keep them from committing delinquent activities (Hirschi, 1969). In other words, adolescents’ relationship with peers could be of great importance in preventing them from conducting risk behaviors such as PSU. This notion is supported 3

by empirical studies. Several cross-sectional studies have reported that SSR is negatively associated with adolescents’ PSU (Ihm, 2018; Jahng, 2019; Wang et al., 2017; Wang et al., 2019). Furthermore, a longitudinal study reported that higher peer relationship satisfaction was correlated with less PSU among adolescents (Bae, 2015). In addition, one intervening study found that the risk of adolescents’ PSU was reduced by a short-term SSR enhancement program (Kim et al., 2018). However, little is known regarding the mechanisms underlying the link between SSR and PSU. Exploring these mechanisms would shed light on the prevention and intervention of adolescents’ PSU. Therefore, the purpose of this study is to extend the above research findings by exploring the underlying mediating and moderating mechanisms in this relation. Specifically, we would develop a moderated mediation model linking SSR and PSU through materialism (i.e. mediator), and investigate the moderating role of narcissism in the indirect relationship between SSR and PSU. 1.1 Materialism as mediator Materialism represents the importance of material possessions and consumption in one’s pleasure seeking (Richins & Dawson, 1992). Individuals high in material values tend to believe that purchasing or acquiring material goods is crucial to their life satisfaction and well-being (Kasser, 2016). Previous studies have well linked materialism to several distinct forms of personal, social, and development issues (Kasser, Ryan, Zax, & Sameroff, 1995; Sharif & Khanekharab, 2017), such as low self-esteem (Chaplin & John, 2010; Jiang, Zhang, Ke, Hawk, & Qiu, 2015), impaired well-being (Kasser et al., 2014), and poor interpersonal relationships (Kasser & Ryan, 2001). Some researchers even regard materialism as an external manifestation of one’s basic unmet psychological needs and insecurities (Rindfleisch, Burroughs, & Wong, 2008). According to the escape theory (Donnelly, Ksendzova, Howell, Vohs, & Baumeister, 2016) and motivation theory (Burroughs et al., 2013), when individuals feel insecure and hold negative views of themselves, they favor a consumption-based strategy (e.g., overspending and borrowing) to avoid negative emotions and to escape from aversive self-awareness. Thus, materialism could be an important coping mechanism to improve self, such as self-esteem or self-worth, although its effect may be limited, short-lived, and even detrimental (Donnelly et al., 2016; Shrum et al., 2013). SSR may be negatively related to adolescent materialism. Materialism seems to reach its peak in adolescence, when individuals begin to link external sources, such as material goods or financial success with personal worth, happiness, and social status (Chan, 2013). Prior studies have shown that 4

family environments, such as family socioeconomic status and parenting style, could affect adolescents’ materialistic values (Roberts, Manolis, & Tanner, 2003). Considering the role of peer relationships in adolescence development, it is important to investigate whether and how the social environments such as SSR influence adolescents’ materialism. Some studies have shown that when adolescents have difficulty in developing intimate relationships with peers, they turn to materialistic values to compensate for the need to attach to a group (Isaksen & Roper, 2012; Jiang et al., 2015; Wooten, 2006). In other words, adolescents with poor peer relationships could value materialism more. For example, studies showed that peer rejection is positively associated with materialism (Banerjee & Dittmar, 2008). Specifically, when being socially rejected, adolescents are more likely to value materialism, not only to avoid ridicules and jokes (Wooten, 2006), but also to establish and maintain peer relationships (Isaksen & Roper, 2012). Conversely, supportive peers would decrease adolescents’ materialism via strengthening adolescents’ self-esteem (Chaplin & John, 2010). In addition, Jiang et al. (2015) provided evidence for the causal relation between peer relationships and materialism by showing that, compared with adolescents who recalled having experiences of being accepted by peers, those who recalled having experiences of being rejected by peers had higher levels of materialism. In summary, the existing evidence suggests that SSR may be negatively associated with adolescents’ materialism. Materialism may be positively related to PSU. As a coping mechanism, materialism is strongly associated with varieties of impulsive behaviors such as compulsive buying, maladaptive consumption, and alcohol use, suggesting that materialism is related to difficulty in controlling one’s behaviors (Dittmar, Bond, Hurst, & Kasser, 2014; Donnelly et al., 2016; Sharif & Khanekharab, 2017). There is converging theoretical and empirical evidence that impulsivity (or less self-control) is a common precursor to problematic internet use (Yellowlees & Marks, 2007) and PSU (Billieux, 2012; Billieux, Van der Linden, & Rochat, 2008; Kim et al., 2016; Kim, Min, Min, Lee, & Yoo, 2018). For example, Billieux (2012) proposed an integrative model describing four pathways leading to PSU. Among these pathways, impulsive pathway describes a link between PSU and impulsivity, which is mainly driven by poor self-regulation. The effect of impulsivity on PSU may be more pronounced in adolescents partly due to the poorer self-regulation (Chóliz, 2012; Steinberg, 2005). Thus, we propose that materialism may be significantly related to adolescents’ PSU. Empirical evidence supports this notion. First, several studies have found that materialism is positively correlated with traditional media usage such as 5

television viewing (Sirgy et al., 2012). Second, individuals high in material values also reported more Internet use for online gaming (Chang & Zhang, 2008), Internet purchases (Kamal, Chu, & Pedram, 2013), and online social interactions (Chu, Windels, & Kamal, 2016). In terms of problematic Internet use, evidence showed that materialists are more likely to report having gaming addiction (Wu, 2013), Internet addiction, and online compulsive buying (Sharif & Khanekharab, 2017). Furthermore, recent studies provide evidence for the influence of materialism on PSU in young adults (Lee, Chang, Cheng, & Lin, 2018; Roberts & Pirog, 2013) and adolescents (Wang et al., 2018). These studies showed that individuals with higher levels of materialism were more likely to report PSU. In sum, the existing studies indicate that adolescents with higher level of materialism are more likely to have higher level of PSU. Based on the literature reviewed above, it is reasonable to assume that SSR would be negatively associated with materialism, which in turn would be positively associated with PSU. That is, materialism would mediate the relationship between SSR and PSU. Although one study identified materialism as a significant mediator between narcissism and compulsive buying (Rose, 2007), research to date provides little insight into the mediating effect of materialism on the relationship between SSR and adolescents’ PSU. Based on the findings in materialism, we propose the first hypothesis: H1: Materialism would mediate the link between SSR and PSU. 1.2 Narcissism as moderator Although SSR may be significantly correlated with PSU via materialism, not all individuals with poor SSR homogeneously display high levels of materialism and PSU. Thus, it is necessary to further examine the potential moderators that contribute to the strength of the associations between SSR, materialism, and PSU. Narcissism is a personality trait that defined as an inflated self-view and a grandiose sense of superiority, dominance, and entitlement (Raskin & Terry, 1988). Narcissism may moderate the link between SSR and materialism. According to the social online self-regulation theory (Ozimek, Baer, & Förster, 2017), people tend to use different self-regulatory strategies to attain desired states and to avoid undesired states in both real and virtual environments. Narcissists are skilled in forming short-term relationship, such as being liked and perceived as confident, entertaining, and excited in initial social interaction (Jonason, Baughman, Carter, & Parker, 2015), while being incapable of building and maintaining long-term relationships which require face6

to-face emotional investments (Miller, Campbell, & Pilkonis, 2007). Smartphones provide an accessible platform of social media use for narcissists to form a large number of loose social connections (Campbell & Foster, 2002). Thus, it is reasonable to postulate that narcissistic individuals may use social networks on smartphone to form and maintain social connections rather than to seek for material goods as compensation for a lack of sociability and social networking in real world. In other words, narcissism may play a buffering role in the association between peer relationship and materialism. A meta-analysis study reported that narcissism was positively associated with the number of friends in social media such as Facebook (Liu & Baumeister, 2016). These online relationships may alleviate the effect of poor SSR in real life on materialism, as online relationships could satisfy narcissists’ need for seeking attention and approval (Buffardi & Campbell, 2008), as well as for belonging to others (Casale & Fioravanti, 2018). Recently, one longitudinal study supported this notion by showing that adolescents with higher levels of narcissism and social rejection in initial test reported more attention-seeking motives for social interaction via mobile-based social media one year later (Hawk, van den Eijnden, van Lissa, & ter Bogt, 2019). Narcissism may also moderate the relationship between materialism and PSU. Narcissism has been examined in relation to various problem behaviours such as problem gaming (Kircaburun, Jonason, & Griffiths, 2018), problematic social media use (Andreassen, Pallesen, & Griffiths, 2017; Casale & Fioravanti, 2018; Hawk et al., 2019), and PSU (Balta et al., 2019; Hawk et al., 2019; Hussain, Griffiths, & Sheffield, 2017; Pearson & Hussain, 2015). Studies show that narcissists tend to use mobile-based social media for self-presentation because mobile devices such as smartphones provide a platform for individuals to instantly share their experiences and feelings with their social networks (Hawk et al., 2019) such as Wechat (Wang, 2017). In addition, studies reported that individuals high in narcissism, like those high in materialism, have a stronger desire to use social media for social comparison (Krizan & Bushman, 2011; Ozimek, Bierhoff, & Hanke, 2018; Ozimek & Förster, 2017). Given that narcissism is positively associated with materialism (Rose, 2007) such as consumer behavior (Cisek et al., 2014), and that presentation of one’s materialistic possession could be a means to attract attention and admiration from others as well as to show their superiority and higher social status in social interaction, it is reasonable to assume that high levels of narcissism may exacerbate the association between materialism and PSU. Specifically, narcissistic individuals may place a high value on material goods and then tend to share them in social media for self-promotion. This could urge them 7

to increase the use of social media, which in turn triggers PSU. In contrast, those with low levels of narcissism may be less likely to use material goods to attract others’ attention and admiration for online self-promotion, and therefore may be less engaged in PSU. Based on the literature, we propose the second hypothesis: H2: Narcissism would moderate the indirect relationships between SSR and PSU. 1.3 The present study Taken together, the purposes of the present study were threefold: first, we aim to examine whether SSR would be significantly linked with adolescents’ PSU; second, whether the link between SSR and PSU would be mediated by materialism; third, whether the indirect relationship between SSR and PSU via materialism would be moderated by narcissism (see Fig. 1). 2. Methods 2.1. Participants Seven hundred and twelve adolescents from two middle schools in Hebei province of China participated in this study. Eight adolescents were excluded from statistical analysis because of not reporting their gender. Among the final sample size, 49.9% (N = 359) were females. The adolescents’ age ranged from 12 to 17, with an average age of 13.66 years (SD = 1.83). All the participants took part in this study after obtaining informed consent from them and their teachers. 2.2. Measures 2.2.1. Student-student relationship (SSR) The Student-Student Relationship Scale developed by Jiang (2002) was used to assess the quality of the relationship between adolescents themselves and their peers. The scale consists of 8 items. Each item was assessed on a 5-point Likert scale, which ranges from 1 = strongly disagree to 5 = strongly agree, with higher total scores indicating better SSR. An example of items includes: “Students support and encourage each other”. The scale has been widely applied to the Chinese adolescents and has shown good reliability and validity (Wang et al., 2019; Xie, Zhao, Xie, & Lei, 2016). In the present study, the Cronbach α for this scale was .89. 2.2.2. Problematic smartphone use (PSU) The Smartphone Addiction Scale was used to assess adolescents’ PSU. The scale consists of 10 items (Kwon, Kim, Cho, & Yang, 2013). Each item was assessed on a 6-point Likert scale, which 8

ranges from 1 = strongly disagree to 6 = strongly agree. Response of each item was summed to generate a composite score, which range from 10 to 60, with higher scores indicating higher levels of PSU. An example of items includes: “Missing planned work due to smartphone use”. The scale has been proved to be a reliable and valid tool for assessing adolescents’ PSU among the Western (e.g. Swiss) (Dey et al., 2019) and non-Western populations (e.g., Chinese) (Wang et al., 2017; Wang et al., 2018). In the present study, the Cronbach α for this scale was .92. 2.2.3. Materialism The Material Values Scale developed by Richins (2004) was used to assess participants’ materialism. The scale consists of 15 items divided in three dimensions, i.e., success, centrality and happiness. Response to each item was rated on a 5-point Likert scale, which ranges from 1 = strongly disagree to 5 = strongly agree. An example item is “Some of the most important achievements in life include acquiring material possessions”. In the present study, the Cronbach α for this scale was .78. 2.2.4. Narcissism Narcissism was measured by the Single Item Narcissism Scale developed by Konrath and colleagues (2014) via a single item: “To what extent do you agree with this statement: I am a narcissist. (Note: The word ‘narcissist’ means egotistical, self-focused, and vain.).” Response to this item ranges from 1 = not very true to me to 7 = very true to me, with higher scores indicating higher levels of narcissism. This scale has been widely used in previous studies and has proved to be a valid and stable measurement (Özsoy, Rauthmann, Jonason, & Ardıç, 2017). 2.3. Procedure The study was approved by the first author’s University Ethics Committee. Participants voluntarily participated in the present study and completed the self-report questionnaires in a classroom after informed consents were obtained. In addition, participants were informed of the anonymity of this study and their right to withdraw from the research. All participants were given a pen as an incentive after the survey. It took approximately 30 minutes to complete these questionnaires. 2.4. Statistical analyses Statistical analyses were performed using SPSS 20.0. First of all, we calculated descriptive statistics and the Pearson correlation coefficients among all the variables. Secondly, we carried out a 9

mediation analysis with SSR as the predictor, PSU as the outcome variable, materialism as the mediator. This mediation analysis was performed using the PROCESS macro (Model 4) for SPSS programmed by Hayes (2013). Thirdly, to test the moderating effects of narcissism on the links between SSR and materialism, and between materialism and PSU, we conducted a hierarchical regression procedure recommended by Baron and Kenny (1986), using the PROCESS macro (Model 58). An empirical 95% confidence interval (95% CI) not including zero indicate that the mediating effect of materialism in Model 4 and the moderating effect of narcissism in model 58 were significant, based on a bootstrap random sample (n = 5000). Note that before detecting for mediating and moderating effects, all variables involved were standardized to reduce problems linked with multicollinearity between the interaction items and the main effects. 3. Results 3.1. Preliminary analyses Means, standard deviations (SD) and the Person correlations among the variables of SSR, PSU, materialism, and narcissism are presented in Table 1. As the results demonstrated, adolescents having poor SSR were likely to have high levels of PSU and materialism. Adolescents with high levels of materialism and narcissism were likely to have high levels of PSU. Besides, materialism was positively correlated with narcissism. 3.2. Testing for mediation effect In Hypothesis 1, we predicted that materialism would mediate the relationship between SSR and PSU. This hypothesis was tested with Model 4 of the PROCESS macro (Hayes, 2013). As Table 2 showed, SSR was negatively associated with materialism (β= -0.262, p < 0.001), which in turn was positively related to PSU (β= 0.419, p < 0.001). Therefore, the present study confirmed Hypothesis 2 that materialism mediated the relation between SSR and PSU (indirect effect = -0.11, SE = 0.02, 95% CI = [-0.15, -0.07]). The mediation effect accounts for 44% [-0.11/(-0.11-0.14)] of the total effect. Therefore, Hypothesis 1 was supported. 3.3. Testing for moderated mediation In Hypothesis 2, we predicted that narcissism would moderate the links between SSR and materialism, as well as the relationship between materialism and PSU. Therefore, we used Model 58 of PROCESS macro (Hayes, 2013) to test the moderated mediation hypothesis. As Table 3 showed, in 10

Model 1 SSR was significantly associated with materialism, and this association was moderated by narcissism. Thus, the relation between SSR and materialism was moderated by narcissism (β = 0.065, SE = 0.032, p < 0.05). For descriptive purpose, this study plotted SSR on materialism, separately for low and high levels of narcissism (Fig. 2). Especially, simple slope tests showed that for individuals with low narcissism, the negative association between SSR and materialism was stronger, that is, poor SSR was negatively associated with higher levels of materialism (βsimple = -0.313, p < 0.001). While for individuals with high narcissism, the negative association between SSR and materialism was weaker (βsimple = -0.183, p < 0.001). Besides, in model 2 the relation between materialism and PSU was moderated by narcissism (β = 0.069, SE = 0.032, p < 0.05). For descriptive purpose, we plotted materialism against PSU, separately at high and low levels of narcissism (Fig. 3). Simple slope test showed that for individuals with high level of narcissism, higher level of materialism was linked with higher level of PSU (βsimple = 0.462, p < 0.001). While for individual with low level of narcissism, the relation between materialism and PSU was weaker (βsimple = 0.324, p < 0.001). The bias-corrected percentile bootstrap analyses further confirmed Hypothesis 2 that the indirect effect of SSR on PSU via materialism was moderated by narcissism. Especially, for adolescents with high level of narcissism, the indirect relationship between SSR and PSU was significantly stronger (β = -0.101, SE = .025, 95% CI = [-0.158, -0.057]). While for adolescents with low level of narcissism, the indirect relationship between SSR and PSU was significantly weaker (β = -0.084, SE = .026, 95% CI = [-0.137, -0.035]). Thus, Hypothesis 2 was supported. 4. Discussion The effect of SSR on adolescents’ PSU has received empirical support (Bae, 2015; Jahng, 2019; Wang et al., 2017; Wang et al., 2019). However, the mediating and moderating mechanisms underpinning this relation remain largely unexplored. The present study explored this association by examining whether materialism would mediate this association, and whether narcissism would moderate the indirect relations between SSR and PSU. The results showed that materialism partially mediated the association between SSR and PSU, and narcissism moderated the indirect relations between SSR and PSU. 4.1 The mediating role of materialism Consistent with our expectations, the results showed that materialism mediated the relation between SSR and PSU. That is, adolescents with poor peer relationships are more likely to have higher 11

levels of materialism, which in turn leads to an increase in PSU. These findings in the present study provide the first evidence for the role of materialism in linking SSR with PSU, and indicate that materialism can serve as one of the coping mechanisms that lead to adolescents’ higher level of PSU when they are in poor relationship with peers. In the previous researches on adolescents’ PSU, ecological circumstance researchers and personality researchers focused on different parts, with the former emphasizing the influence of family and social circumstances such as peer relations (Ihm, 2018; Jahng, 2019), while the latter emphasizing the influence of personal value system such as materialism (Lee et al., 2018). The possible link between SSR and materialism has been largely neglected by researchers. To our knowledge, there are no study has integrated factors from ecological circumstance and personal value system to investigate adolescents’ PSU. Only one study to date showed that personal traits such as self-esteem played a mediating role in the effect of SSR on PSU (Wang et al., 2017). The present study extends the existing literature and indicates that adolescents with poor SSR could be more prone to PSU via their value systems such as materialism. Furthermore, the first-stage and second-stage in the mediation model are also noteworthy. To be specific, for the first stage, SSR was significantly and negatively correlated with materialism. This finding is consistent with the escape theory (Donnelly et al., 2016) and the motivation theory (Burroughs et al., 2013), as well as previous studies showing that individuals with a poor support network have a propensity to adopt passive strategies, such as denial and social withdrawal, to deal with the stressful realities (Jiang et al., 2015). Materialism, as a copying mechanism, has been increasingly common in adolescents given the popularity of consumerism among the young generation. Thus, for adolescents with poor SSR, they are more likely to emphasize materialistic values. For the second stage, materialism was significantly positively correlated with PSU. This finding is congruent with previous studies showing that individuals high in materialism are more likely to get addicted to Internet/smartphones (Lee et al., 2018; Lee et al., 2014; Roberts & Pirog, 2013; Wang et al., 2018). There can be at least three reasons for this association. First, adolescents high in materialism may have a more positive attitude towards smartphones as a social status symbol in the peer group (Abeele & Roe, 2013), which makes them more likely to indulge in smartphone use. Second, smartphone provides an online shopping platform for materialists to buy what they want. Third, smartphone-based social media such as Wechat/Facebook could serve as a medium to satisfy materialists’ needs associated with self-presentation, social comparison, and the feeling of belonging to others (Ozimek et al., 2017; 12

Ozimek & Förster, 2017). It is worth noting that adolescents with the same level of materialism as adults might display higher levels of PSU, because they exhibit impulsiveness and poor self-control, and then hardly reject using smartphones (Billieux, 2012; Billieux et al., 2016; Kim et al., 2016; Kim et al., 2018). Besides, given that adolescents and adults engage in different online activities (Hwang & Park, 2017), future study may examine whether and how materialism is differentially associated with PUS between adolescents and adults. 4.2 The moderating role of narcissism The present study showed that narcissism moderated the relation between SSR and materialism. Specially, the association between SSR and materialism was weaker among adolescents with higher levels of narcissism. This finding indicates that narcissism may work as a buffer in the effect of SSR on materialism. This moderating effect could be explained by the self-regulation theory (Ozimek et al., 2017). According to this theory, adolescents with higher levels of narcissism tend to use varieties of interpersonal skills to seek for more social connections and social feedbacks in managing their selfesteem (Błachnio & Przepiórka, 2018; Liu & Baumeister, 2016; Ozimek et al., 2018), as adolescents’ self-esteem is positively associated with peer relationships (Gorrese & Ruggieri, 2013; Birkeland, Breivik, & Wold, 2014). Thus, it is understandable that adolescents who scored higher on narcissism could effectively regulate their self-esteem when they have a poor relationship with peers and thus are less likely to value materialism. Previous studies showing that narcissism, to some extent and in some aspects, could be adaptive and prevent narcissists from social anxiety and depression (Cai & Luo, 2018; Shi, Luo, Yang, Liu, & Bao, 2018). For example, Shi et al. (2018) showed that adaptive narcissism was linked to positive affective experiences and self-esteem. The findings of the present study are in accordance with the previous researches (Cai & Luo, 2018; Shi et al., 2018), and extend these researches by showing that, albeit poor peer relationship, adolescents high in (adaptive) narcissism may have high self-esteem and a more positive attitude towards peer relationship, thereby making them less prone to materialism. In addition, narcissism moderated the relation between materialism and PSU. Specially, the relation between materialism and PSU was stronger for adolescents with higher levels of narcissism. In other words, high levels of narcissism exacerbate the association between materialism and PSU. This finding could be explained by the social online self-regulation theory (Ozimek et al., 2017). That is, adolescents scoring higher on narcissism may use material possessions to compare themselves with 13

others in social networking platforms, which increase the risk of PSU. For narcissists, online social media, such as Facebook and Wechat, has become a good platform for the manifestation of narcissistic behavior. First, it provides a good place for social comparison, which can be realized by presenting one’s wealth and possessions (Krizan & Bushman, 2011; Ozimek et al., 2018). For instance, previous study showed that individuals high in narcissism reported higher levels of social comparison via social media such as Facebook (Ozimek et al., 2018). Second, smartphone-based social networking sites provide a medium for self-presentation. In order to keep their positive and attractive impression, narcissists may tend to present a set of material-relevant information rather than only self-related information (e.g. selfie photographs) to obtain desired gratifications (Andreassen et al., 2017; Ozimek et al., 2018), and thus the positive association between materialism and PSU could become stronger for them. This finding is consistent with previous studies reporting that some aspect of narcissism could be maladaptive (Cai, Shi, Fang, & Luo, 2015) and associated with depression, low self-esteem and impulsive behaviors (Bosson et al., 2008), which may exacerbate the influence of poor peer relation on adolescent problem behaviors. 4.3 Implications The findings in the current study have several theoretical and practical implications. From the theoretical perspectives, these findings offer an empirical framework to examine the mediating role of materialism in the association between SSR and PSU and the moderating role of narcissism in the indirect links among these factors. Thus, these results could shed light on the underlying mechanism between SSR and PSU. From the practical perspectives, the present findings are beneficial to develop educational practices, interventions, and policies designed to decrease adolescents’ PSU and materialism (Kasser, 2016). For materialism, some measures should be taken to help adolescents shift away from materialistic values to intrinsic values or goals, for instances, improving adolescents’ feeling of security (Chaplin & John 2007), building high-quality interpersonal relationships (Clark et al., 2011), reflection on death (Dechesne et al., 2003), and recalling spiritual events (Stillman et al., 2012). Besides, since the indirect links between SSR and PSU were moderated by narcissism, targeted intervention strategies should be developed according to the adolescents’ type and levels of narcissism, and especially pay attention to the maladaptive aspect while leaving the adaptive aspect intact. For adolescents with adaptive narcissism, school educators should provide a continuum of interventions from purely supportive to highly interpretive and expressive nature (Kealy & Ogrodniczuk, 2012). 14

4.4 Limitations and future directions Several limitations of the present study should be considered. First, the data were collected through adolescents’ self-reported measures which were susceptible to biases, although the bias was not strong in the case of anonymity and confidentially suggested by previous studies on adolescent’s self-reported risk behaviors (Tourangeau & Yan, 2007). Multiple methods of assessment (e.g., peerand parent-reported) should be applied to minimize the impact of response bias. Second, the present study treated narcissism as a singular construct, and did not distinguish between distinct aspects of narcissism (i.e., adaptive and maladaptive narcissism). Given that these two facets of narcissism are differentially associated with problem behaviors such as problematic use of social networking sites (Cai et al., 2015; Shi et al., 2018), their different influence on adolescent problem behaviors should be taken into account. For instance, future research can use the narcissistic personality inventory (Raskin and Terry, 1988) to gain further insight into the role of narcissism in the associations among SSR, materialism and PSU. Third, the present study was a cross-sectional design, making it difficult to draw causal inferences regarding the associations between SSR and PSU. There can be a bidirectional association between SSR and problem behaviors in adolescents (Chng, Li, Liau, & Khoo, 2015). Thus, future research should utilize longitudinal designs to address the causality of these relationships.

15

Acknowledgement The present study was supported by the Outstanding Innovative Talents Cultivation Funded Programs 2017 of Renmin University of China.

References Abeele, M. V., & Roe, K. (2013). Adolescents’ school experience and the importance of having a “cool” mobile phone: Conformity, compensation and resistance? Poetics, 41(3), 265–293. Anderson, M., & Jiang, J. (2018). Teens, social media & technology 2018. Pew Research Centre, Washington DC, available at: http: //assets.pewresearch.org/wp-content/uploads/sites/ 14/2018/05/31102617 /PI_2018.05.31_TeensTech_FINAL.pdf (accessed on 10 June 2018). Andreassen, C. S., Pallesen, S., & Griffiths, M. D. (2017). The relationship between addictive use of social media, narcissism, and self-esteem: Findings from a large national survey. Addictive Behaviors, 64, 287–293. Bae, S. M. (2015). The relationships between perceived parenting style, learning motivation, friendship satisfaction, and the addictive use of smartphones with elementary school students of South Korea: Using multivariate latent growth modeling. School Psychology International, 36(5), 513–531. Balta, S., Jonason, P., Denes, A., Emirtekin, E., Tosuntaş, Ş. B., Kircaburun, K., & Griffiths, M. D. (2019). Dark personality traits and problematic smartphone use: The mediating role of fearful attachment. Personality and Individual Differences, 149, 214–219. Banerjee, R., & Dittmar, H. (2008). Individual differences in children's materialism: The role of peer relations. Personality and Social Psychology Bulletin, 34(1), 17–31. Baron, R. M., & Kenny, D. A. (1986). The moderator–mediator variable distinction in social psychological research: Conceptual, strategic, and statistical considerations. Journal of Personality and Social Psychology, 51(6), 1173–1182.

16

Birkeland, M. S., Breivik, K., & Wold, B. (2014). Peer acceptance protects global self-esteem from negative effects of low closeness to parents during adolescence and early adulthood. Journal of Youth and Adolescence, 43(1), 70–80. Billieux, J. (2012). Problematic use of the mobile phone: a literature review and a pathways model. Current Psychiatry Reviews, 8(4), 299–307. Billieux, J., Van der Linden, M., & Rochat, L. (2008). The role of impulsivity in actual and problematic use of the mobile phone. Applied Cognitive Psychology, 22(9), 1195–1210. Błachnio, A., & Przepiórka, A. (2018). Facebook intrusion, fear of missing out, narcissism, and life satisfaction: A cross-sectional study. Psychiatry Research, 259, 514–519. Bosson, J. K., Lakey, C. E., Campbell, W. K., Zeigler–Hill, V., Jordan, C. H., & Kernis, M. H. (2008). Untangling the links between narcissism and self-esteem: A theoretical and empirical review. Social and Personality Psychology Compass, 2(3), 1415–1439. Buffardi, L. E., & Campbell, W. K. (2008). Narcissism and social networking web sites. Personality and Social Psychology Bulletin, 34(10), 1303–1314. Bukowski, W. M., Motzoi, C., & Meyer, F. (2008). Friendship as process, function, and outcome. In K. H. Rubin, W. M. Bukowski, & B. Laursen (Eds.), Handbook of peer interactions, relationships, and groups, social, emotional, and personality development in context (pp. 217–231). New York: Cambridge University Press. Burroughs, J. E., Chaplin, L. N., Pandelaere, M., Norton, M. I., Ordabayeva, N., Gunz, A., & Dinauer, L. (2013). Using motivation theory to develop a transformative consumer research agenda for reducing materialism in society. Journal of Public Policy & Marketing, 32, 18–31. Cai, H., & Luo, Y. L. L. (2018). Distinguishing between adaptive and maladaptive narcissism. in The Handbook of Trait Narcissism: Key Advances, Research Methods, and Controverses (pp. 97– 104)., eds T. Hermann, A. B. Brunell, and J. Foster (Berlin: Springer). Cai, H., Shi, Y., Fang, X., & Luo, Y. L. (2015). Narcissism predicts impulsive buying: phenotypic and genetic evidence. Frontiers in Psychology, 6, 881. Campbell, W. K., & Foster, C. A. (2002). Narcissism and commitment in romantic relationships: An investment model analysis. Personality and Social Psychology Bulletin, 28(4), 484–495. 17

Casale, S., & Fioravanti, G. (2018). Why narcissists are at risk for developing Facebook addiction: The need to be admired and the need to belong. Addictive Behaviors, 76, 312–318. Chan, K. (2013). Development of materialistic values among children and adolescents. Young Consumers, 14, 244–257. Chang, J. H., & Zhang, H. (2008). Analyzing online game players: From materialism and motivation to attitude. Cyberpsychology & Behavior, 11(6), 711–714. Chaplin, L. N., & John, D. R. (2007). Growing up in a material world: Age differences in materialism in children and adolescents. Journal of Consumer Research, 34(4), 480–493. Chaplin, L. N., & John, D. R. (2010). Interpersonal influences on adolescent materialism: A new look at the role of parents and peers. Journal of Consumer Psychology, 20(2), 176–184. Chóliz, M. (2012). Mobile-phone addiction in adolescence: The test of mobile phone dependence (TMD). Progress in Health Sciences, 2(1), 33–44. Chng, G. S., Li, D., Liau, A. K., & Khoo, A. (2015). Moderating effects of the family environment for parental mediation and pathological internet use in youths. Cyberpsychology, Behavior, and Social Networking, 18(1), 30–36. Chu, S. C., Windels, K., & Kamal, S. (2016). The influence of self-construal and materialism on social media intensity: A study of China and the United States. International Journal of Advertising, 35(3), 569–588. Cisek, S. Z., Sedikides, C., Hart, C. M., Godwin, H. J., Benson, V., & Liversedge, S. P. (2014). Narcissism and consumer behaviour: a review and preliminary findings. Frontiers in Psychology, 5, 232. Clark, M. S., Greenberg, A., Hill, E., Lemay, E. P., Clark-Polner, E., & Roosth, D. (2011). Heightened interpersonal security diminishes the monetary value of possessions. Journal of Experimental Social Psychology, 47(2), 359–364. CNNIC (2018, July). The 42st China Statistical Report on Internet Development. Retrieved from http://www.cnnic.net.cn/hlwfzyj/hlwxzbg/hlwtjbg/201808/t20180820_70488.htm

18

Demirci, K., Akgönül, M., & Akpinar, A. (2015). Relationship of smartphone use severity with sleep quality, depression, and anxiety in university students. Journal of Behavioral Addictions, 4(2), 85–92. Dechesne, M., Pyszczynski, T., Arndt, J., Ransom, S., Sheldon, K. M., Van Knippenberg, A., & Janssen, J. (2003). Literal and symbolic immortality: The effect of evidence of literal immortality on self-esteem striving in response to mortality salience. Journal of Personality and Social Psychology, 84(4), 722–737. Dey, M., Studer, J., Schaub, M. P., Gmel, G., Ebert, D. D., Lee, J. Y. C., & Haug, S. (2019). Problematic smartphone use in young Swiss men: Its association with problematic substance use and risk factors derived from the pathway model. Journal of Behavioral Addictions, 1–9. Dittmar, H., Bond, R., Hurst, M., & Kasser, T. (2014). The relationship between materialism and personal well-being: A meta-analysis. Journal of Personality and Social Psychology, 107(5), 879–924. Donnelly, G. E., Ksendzova, M., Howell, R. T., Vohs, K. D., & Baumeister, R. F. (2016). Buying to blunt negative feelings: Materialistic escape from the self. Review of General Psychology, 20(3), 272–316. Elhai, J. D., Dvorak, R. D., Levine, J. C., & Hall, B. J. (2017). Problematic smartphone use: A conceptual overview and systematic review of relations with anxiety and depression psychopathology. Journal of Affective Disorders, 207, 251–259. Gorrese, A., & Ruggieri, R. (2013). Peer attachment and self-esteem: A meta-analytic review. Personality and Individual Differences, 55(5), 559–568. Hayes, A. F. (2013). Introduction to mediation, moderation, and conditional process analysis: A regression-based approach. New York, NY: Guilford Press. Hawk, S. T., van den Eijnden, R. J., van Lissa, C. J., & ter Bogt, T. F. (2019). Narcissistic adolescents' attention-seeking following social rejection: Links with social media disclosure, problematic social media use, and smartphone stress. Computers in Human Behavior, 92, 65–75. Hirschi, T. (1969). Causes of delinquency. Berkeley, CA: University of California Press.

19

Hussain, Z., Griffiths, M. D., & Sheffield, D. (2017). An investigation into problematic smartphone use: The role of narcissism, anxiety, and personality factors. Journal of Behavioral Addictions, 6(3), 378–386. Hwang, Y., & Park, N. (2017). Is smartphone addiction comparable between adolescents and adults? Examination of the degree of smartphone use, type of smartphone activities, and addiction levels among adolescents and adults. ITU. (2018). ICT facts and figures 2016. In. Ihm, J. (2018). Social implications of children’s smartphone addiction: The role of support networks and social engagement. Journal of Behavioral Addictions, 7(2), 473–481. Isaksen, K. J., & Roper, S. (2012). The Commodification of Self-Esteem: Branding and British Teenagers. Psychology & Marketing, 29(3), 117–135. Jahng, K. E. (2019). Maternal abusive parenting and young South Korean adolescents' problematic smartphone use: The moderating effects of time spent hanging out with peers and trusting peer relationships. Children and Youth Services Review, 98, 96–104. Jiang, G. R. (2002). Research on classroom social ecology environment. Wuhan, China: Central China Normal University Press. Jiang, J., Zhang, Y., Ke, Y., Hawk, S. T., & Qiu, H. (2015). Can’t buy me friendship? Peer rejection and adolescent materialism: Implicit self-esteem as a mediator. Journal of Experimental Social Psychology, 58, 48–55. Jonason, P. K., Baughman, H. M., Carter, G. L., & Parker, P. (2015). Dorian gray without his portrait: Psychological, social, and physical health costs associated with the dark triad. Personality and Individual Differences, 78, 5–13. Kamal, S., Chu, S. C., & Pedram, M. (2013). Materialism, attitudes, and social media usage and their impact on purchase intention of luxury fashion goods among American and Arab young generations. Journal of Interactive Advertising, 13(1), 27–40. Kasser, T. (2016). Materialistic values and goals. Annual review of psychology, 67, 489–514. Kasser, T., Rosenblum, K. L., Sameroff, A. J., Deci, E. L., Niemiec, C. P., Ryan, R. M., ... & Hawks, S. (2014). Changes in materialism, changes in psychological well-being: Evidence from three longitudinal studies and an intervention experiment. Motivation and Emotion, 38(1), 1–22. 20

Kasser, T., & Ryan, R. M. (2001). Be careful what you wish for: Optimal functioning and the relative attainment of intrinsic and extrinsic goals. In P. Schmuck & K. M. Sheldon (Eds.), Life goals and well-being: Towards a positive psychology of human striving (pp. 116–131). Goettingen, Germany: Hogrefe & Huber. Kasser, T., Ryan, R. M., Zax, M., & Sameroff, A. J. (1995). The relations of maternal and social environments to late adolescents' materialistic and prosocial values. Developmental Psychology, 31(6), 907–914. Kealy, D., & Ogrodniczuk, J. S. (2012). Pathological narcissism: A front-line guide. Practice, 24(3), 161–174. Kim, Y., Jeong, J. E., Cho, H., Jung, D. J., Kwak, M., Rho, M. J., Yu, H., Kim, D. J., & Choi, I. Y. (2016). Personality factors predicting smartphone addiction predisposition: Behavioral inhibition and activation systems, impulsivity, and self-control. PLOS One, 11(8), 1–15. Kim, T. H., Jun, Y. S., Shin, Y. T., Lim, S. H., & Seo, J. W. (2018). A preliminary study on the effectiveness of the peer relationship enhancement program in adolescents at risk for internet and smartphone addiction. Journal of the Korean Academy of Child and Adolescent Psychiatry, 29(2), 40–46. Kim, H. J., Min, J. Y., Min, K. B., Lee, T. J., & Yoo, S. (2018). Relationship among family environment, self-control, friendship quality, and adolescents’ smartphone addiction in South Korea: Findings from nationwide data. PLOS One,13(2), e0190896. Kircaburun, K., Jonason, P. K., & Griffiths, M. D. (2018). The Dark Tetrad traits and problematic online gaming: The mediating role of online gaming motives and moderating role of game types. Personality and Individual Differences, 135, 298–303. Konrath, S., Meier, B. P., & Bushman, B. J. (2014). Development and validation of the single item narcissism scale (SINS). PLOS One, 9(8), e103469. Korean Information Society Development Institute (2018). The proportion of access to smartphone. Retrieved on May 2, 2018 from http:// stat.kisdi.re.kr /MediaPanel/ MediaPanel. aspx? tablename =TBR_B_CELLPHONE.

21

Krizan, Z., & Bushman, B. J. (2011). Better than my loved ones: Social comparison tendencies among narcissists. Personality and Individual Differences, 50(2), 212–216. Kwon, M., Kim, D. J., Cho, H., & Yang, S. (2013). The smartphone addiction scale: development and validation of a short version for adolescents. PLOS One, 8(12), e83558. Lee, Y. K., Chang, C. T., Cheng, Z. H., & Lin, Y. (2018). How social anxiety and reduced self-efficacy induce smartphone addiction in materialistic people. Social Science Computer Review, 36(1), 36– 56. Lepp, A., Barkley, J. E., & Karpinski, A. C. (2014). The relationship between cell phone use, academic performance, anxiety, and satisfaction with life in college students. Computers in Human Behavior, 31, 343–350. Liu, D., & Baumeister, R. F. (2016). Social networking online and personality of self-worth: A metaanalysis. Journal of Research in Personality, 64, 79–89. Miller, J. D., Campbell, W. K., & Pilkonis, P. A. (2007). Narcissistic personality disorder: Relations with distress and functional impairment. Comprehensive Psychiatry, 48(2), 170–177. Ozimek, P., Baer, F., & Förster, J. (2017). Materialists on Facebook: The self-regulatory role of social comparisons and the objectification of Facebook friends. Heliyon, 3(11), e00449. Ozimek, P., Bierhoff, H. W., & Hanke, S. (2018). Do vulnerable narcissists profit more from Facebook use than grandiose narcissists? An examination of narcissistic Facebook use in the light of selfregulation and social comparison theory. Personality and Individual Differences, 124, 168–177. Ozimek, P., & Förster, J. (2017). The impact of self-regulatory states and traits on Facebook use: Priming materialism and social comparisons. Computers in Human Behavior, 71, 418–427. Özsoy, E., Rauthmann, J. F., Jonason, P. K., & Ardıç, K. (2017). Reliability and validity of the Turkish versions of dark triad dirty dozen (DTDD-T), short dark triad (SD3-T), and single item narcissism scale (SINS-T). Personality and Individual Differences, 117, 11–14. Pearson, C., & Hussain, Z. (2015). Smartphone use, addiction, narcissism, and personality: A mixed methods investigation. International Journal of Cyber Behavior, Psychology and Learning, 5(1), 17–32.

22

Raskin, R., & Terry, H. (1988). A principal-components analysis of the Narcissistic Personality Inventory and further evidence of its construct validity. Journal of Personality and Social Psychology, 54(5), 890–902. Richins, M. L. (2004). The material values scale: Measurement properties and development of a short form. Journal of Consumer Research, 31(1), 209–219. Richins, M. L., & Dawson, S. (1992). A consumer values orientation for materialism and its measurement: Scale development and validation. Journal of Consumer Research, 19(3), 303–316. Rindfleisch, A., Burroughs, J. E., & Wong, N. (2008). The safety of objects: Materialism, existential insecurity, and brand connection. Journal of Consumer Research, 36(1), 1–16. Roberts, J. A., Manolis, C., & Tanner Jr, J. F. (2003). Family structure, materialism, and compulsive buying: A reinquiry and extension. Journal of the Academy of Marketing Science, 31(3), 300–311. Roberts, J. A., & Pirog III, S. F. (2013). A preliminary investigation of materialism and impulsiveness as predictors of technological addictions among young adults. Journal of Behavioral Addictions, 2(1), 56–62. Rose, P. (2007). Mediators of the association between narcissism and compulsive buying: The roles of materialism and impulse control. Psychology of Addictive Behaviors, 21(4), 576–581. Sharif, S. P., & Khanekharab, J. (2017). Identity confusion and materialism mediate the relationship between excessive social network site usage and online compulsive buying. Cyberpsychology, Behavior, and Social Networking, 20(8), 494–500. Shi, Y., Luo, Y., Yang, Z., Liu, Y., & Bao, H. (2018). Do narcissists enjoy visiting social networking sites? It depends on how adaptive they are. Frontiers in Psychology, 9, 1739. Shrum, L. J., Wong, N., Arif, F., Chugani, S. K., Gunz, A., Lowrey, T. M., ... & Scott, K. (2013). Reconceptualizing materialism as identity goal pursuits: Functions, processes, and consequences. Journal of Business Research, 66(8), 1179–1185. Sirgy, M. J., Gurel-Atay, E., Webb, D., Cicic, M., Husic, M., Ekici, A., ... & Johar, J. S. (2012). Linking advertising, materialism, and life satisfaction. Social Indicators Research, 107(1), 79– 101.

23

Steinberg, L. (2005). Cognitive and affective development in adolescence. Trends in Cognitive Sciences, 9(2), 69–74. Stillman, T. F., Fincham, F. D., Vohs, K. D., Lambert, N. M., & Phillips, C. A. (2012). The material and immaterial in conflict: Spirituality reduces conspicuous consumption. Journal of Economic Psychology, 33(1), 1–7. Tourangeau, R., & Yan, T. (2007). Sensitive questions in surveys. Psychological Bulletin, 133(5), 859– 883. Yellowlees, P. M., & Marks, S. (2007). Problematic internet use or internet addiction? Computers in human behavior, 23(3), 1447–1453. Wang, D. (2017). A study of the relationship between narcissism, extraversion, drive for entertainment, and narcissistic behavior on social networking sites. Computers in Human Behavior, 66, 138–148. Wang, P., Nie, J., Wang, X., Wang, Y., Zhao, F., Xie, X., ... & Ouyang, M. (2018). How are smartphones associated with adolescent materialism? Journal of Health Psychology. Wang, P., Zhao, M., Wang, X., Xie, X., Wang, Y., & Lei, L. (2017). Peer relationship and adolescent smartphone addiction: The mediating role of self-esteem and the moderating role of the need to belong. Journal of Behavioral Addictions, 6(4), 708–717. Wang, P., Wang, X., & Lei, L. (2019). Gender differences between student–student relationship and cyberbullying perpetration: An evolutionary perspective. Journal of Interpersonal Violence, 0886260519865970. Wang, P., Wang, X., Nie, J., Zeng, P., Liu, K., Wang, J., ... & Lei, L. (2019). Envy and problematic smartphone use: The mediating role of FOMO and the moderating role of student-student relationship. Personality and Individual Differences, 146, 136–142. Willemse, I., Waller, G., & Süss, D. (2014). JAMES Jugend, Aktivitäten, Medien-Erhebung Schweiz, Factsheet Befunde 2014. Zurich University of Applied Sciences. Wooten, D. B. (2006). From labeling possessions to possessing labels: Ridicule and socialization among adolescents. Journal of Consumer Research, 33(2), 188–198. Wu, P. C. (2013). Addictive behavior in relation to the happy farm Facebook application. Social Behavior and Personality: An International Journal, 41, 539–554. 24

Xie, X., Zhao, F., Xie, J., & Lei, L. (2016). Symbolization of mobile phone and life satisfaction among adolescents in rural areas of China: Mediating of school-related relationships. Computers in Human Behavior, 64, 694–702.

25

Table 1 Descriptive statistics and correlations of the study variables Variables 1.Age 2.Gender

M

SD

13.661

1.832





3. SSR 4. PSU 5. Mat 6. Nar

3.884 2.6 2.607 3.321

0.814 0.604 0.597 1.751

1 1 -0.125*** -0.20 0.201*** 0.180*** 0.028

2

3

4

5

6

1 -0.059 -0.010 -0.024 -0.041

1 -0.258*** -0.264*** -0.046

1 0.482*** 0.177***

1 0.189***

1

Note: SSR = student-student relationship, PSU = problematic smartphone use. Mat = Materialism, Nar = Narcissism. *** p < .001.

26

Table 2

Variables Age Gender SSR Mat R2 F

Testing the mediation effect of SSR on PSU via materialism Model 1 (Mat) Model 2 (PSU) Coeff.

SE

LLCI

ULCI

Coeff.

SE

LLCI

ULCI

0.173*** -0.027 -0.262***

0.036 0.071 0.036

0.103 -0.168 -0.332

0.244 0.114 -0.192

0.122*** 0.006 -0.137*** 0.419*** 0.261 63.657***

0.033 0.065 0.033 0.034

0.058 -0.121 -0.203 0.352

0.187 0.133 -0.072 0.485

0.101 26.559***

Note: The beta values are standardized coefficients. SE = standard error, LLCI = lower limit of the 95% confidence interval, ULCI = upper limit of the 95% confidence interval. Each column is a regression model that predicts the criterion at the top of the column. SSR = student-student relationship, PSU = problematic smartphone use. Mat = Materialism. *** p< .001.

27

Table 3

Testing the moderated mediation effect of SSR on PSU Variables

Model 1 (Mat)

Model 2 (PSU)

Coeff.

SE

LLCI

ULCI

Coeff.

SE

LLCI

ULCI

Age Gender SSR Nar

0.170*** -0.006 -0.248*** 0.175***

0.032 0.007 0.035 0.035

0.101 -0.145 -0.317 0.106

0.239 0.133 -0.179 0.243

0.122*** 0.006 -0.147*** 0.086**

0.032 0.064 0.033 0.032

0.058 -0.12 -0.212 0.022

0.186 0.132 -0.082 0.149

SSR × Nar Mat Mat × Nar R2

0.065*

0.032

0.001

0.129 0.034 0.028

0.326 0.015

0.461 0.124

0.136

0.393*** 0.069* 0.277

F

22.282***

44.843***

Note: The beta values are standardized coefficients. SSR = student-student relationship, PSU = problematic smartphone use. Mat = Materialism, Nar = Narcissism. * p< .05. ** p< .01. *** p< .001.

28

Materialism

Problematic smartphone use (PSU)

Student-student relationship (SSR)

Narcissism

Fig. 1 The proposed moderated mediation model.

29

Materialism

0.5 0.4 0.3 0.2 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.6

Low narcissism High narcissism

Poor SSR

Good SSR

Fig. 2 Narcissism moderates the relation between SSR and materialism.

30

Low narcissism High narcissism

PSU

0.6 0.5 0.4 0.3 0.2 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5

Low materialism

High materialism

Fig. 3 Narcissism moderates the relation between materialism and PSU.

31

The manuscript or substantial parts of it have not been published and under concurrent consideration by any other journal. The data and the materials, which are presented in this manuscript, do not infringe copyright, and do not include libelous or defamatory contents. The study reported in the manuscript has been performed following the ethics rules suggested by the ethics committees. All authors confirm that they have read and agreed to the content of the manuscript. If accepted, readily reproducible materials described in the manuscript, including all relevant raw data, will be freely available to any scientist wishing to use them for non-commercial purposes.

32

Highlights 1. SSR is negatively related to PSU; 2. Materialism mediates the link between SSR and PSU; 3. Narcissism moderates the link between SSR and materialism; 4. Narcissism moderates the link between materialism and PSU.

33