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In recent years, relationship scientists have made significant contributions to our understanding of the relation between friendship and happiness. Within this chapter, we will review empirical evidence that highlights friendship as a consistent and robust correlate of happiness among young adults. In addition to reviewing prominent indices of friendship (e.g. quantity, quality, satisfaction) that are often addressed within the literature, we will touch on issues such as the degree to which friendship is important for one’s happiness. For example, researchers have shown that in some contexts, the contributions of friendship are dependent upon variables such as romantic relationship status or familial support. Thus, we present evidence that allows one to evaluate the relative importance of friendship for happiness, taking various other factors into account. Additionally, we have provided a review of proposed future directions that may support continued growth of the field, allowing for a more enriched understanding of the link between friendship and happiness.
Melikşah Demir
DOI 10.1007/978-94-017-9603-3
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Melikşah Demir
Department of Psychology
Northern Arizona University
Melikşah Demir, Haley Orthel-Clark, Metin Özdemir *
© Springer Science+Business Media Dordrecht 2015
M. Demir (ed.), !"#$%&'(#)*+%&*,+))#%$''-*#
DOI 10.1007/978-94-017-9603-3_7
M. Özdemir ()#
Center for Developmental Research, School of Law, #
Psychology and Social Work, Örebro University 701 82 Örebro, Sweden
M. Demir
Northern Arizona University, Flagstaff, AZ, USA
H. Orthel-Clark
Truckee Meadows Community College, Reno, NV, USA
S. Bayram Özdemir
Friendship is a cherished, personal relationship among young adults. The popularity
of television shows such as Friends, which has been broadcasted across the globe,
and movies such as Thelma & Louis, Circle of Friends, Good Will Hunting, and I
Love You, Man, highlight the importance of friendships in one’s life. More impor%
tantly, the implicit assumption among laypeople that this invaluable bond plays a
key role in the lives and well-being of young adults, has been recognized and stud%
ied by social scientists. Since the seminal works of Watson (1930), Wilson (1967),
Diener (1984) and theoretical arguments of Sanchez-Hidalgo (1953), significant
progress has been observed in the literature, especially in the last three decades.
During this time period, researchers have documented the importance of friendship
as a robust correlate of happiness. Specifically, this line of research has shown that
various indices of friendship are reliably related to happiness among young adults
across ethnic and cultural groups and has also addressed how friendship is related
to happiness (Demir et al. 2013b). Collectively, the literature leaves no doubt that
friendship has implications for happiness. Yet, as it will be argued in our review,
more research on the topic is needed in order to address some limitations of the
current literature.
In this chapter, we provide an overview of the literature that has been compiled
over the years, assessing the association between friendship and happiness for young
118 M.#Demir#et#al.
adults. As a note, our review will not include studies that address online friendships,
or friendships strictly maintained via social media venues. Our chapter is organized
around three primary focal points that address assessment, theoretical review and
new directions within the field. More specifically, we have provided an overview
of how friendship and happiness are often measured, in an effort to clarify how
these two concepts are construed in the literature. Additionally, we have provided
a brief review of the theoretical arguments, and a detailed account of the empirical
evidence regarding the association between friendship and happiness. Finally, we
have included directions for future research that may promote the development of a
better understanding of the link between friendship and happiness.
Happiness is conceptualized as the combination of cognitive and affective evalua%
tions of one’s own life (Miao et al. 2013; Pavot and Diener 2013). The assessment
of happiness is often based on the measures of global life satisfaction and the rela%
tive weight of positive affect in relation to negative affect. Many well-established
scales exist to measure these components (see Miao et al. 2013 for a review). Ad%
ditional scales assess the individual’s global and subjective feelings of happiness
(Lyubomirksy and Lepper 1999). In some instances, studies rely on a single-item
measure of happiness when investigating the friendship-happiness association (e.g.,
Gladow and Ray 1986).
Friendship is a voluntary interdependence between two individuals that includes
the experience and satisfaction of various provisions (intimacy, support, self-vali%
dation) to varying degrees (Hays 1988; Demir et al. 2014). Friendship is a mixed
blessing such that it also involves conflict (Berndt and McCandless 2009; Solano
1986). Thus, it is appropriate to consider friendship as having two major dimen%
sions: overall quality that includes various provisions and conflict. Commonly used
scales addressing these dimensions include the Network of Relationships Inventory
(NRI) (Furman and Buhrmester 1985) and the McGill Friendship Questionnaire-
Friend’s Functions (MFQ-FF) (Mendelson and Aboud 1999). Another dimension
of friendship that is frequently studied in the literature includes the assessment of
friendship quantity (Demir and Weitekamp 2007; Requena 1995). Friendship quan%
tity is typically measured with a single item, which asks participants to report their
number of close friends. Yet, this dimension alone does not tell much about how
individuals experience their friendships (Demir et al. 2013b). Thus, differentiating
the degree of closeness among one’s friends and assessing the quality and conflict
experienced in every friendship would be ideal. Finally, relationship scholars in the
field have also focused on satisfaction with friends (Jones 1991; Lyubomirsky et al.
2006). This index of friendship has also typically been assessed with a single item
(Michalos#1980; Lyubomirsky et al. 2006); yet there are a few scales adapted (e.g.,
Morry#2003) or developed (e.g., Tsuzuki and Matsui 2000) to measure friendship
satisfaction. Overall, these four indices of friendship (i.e. quantity, quality, conflict,
and satisfaction) have been studied in the literature when investigating the relation%
ships between friendship and happiness.
Individuals across all walks of life and scholars studying friendship have the com%
mon assumption that friendship is important for happiness. Not surprisingly, friends
and friendships (having a friend, interactions with friends) have emerged as themes
or factors in a plethora of studies that have investigated sources of happiness among
young adults across cultures (Caunt et al. 2013; Coleta and Coleta 2006; Lu and
Shih#1997; Tafarodi et al. 2012). Yet, the question still remains, why would friend%
ship be related to happiness? Although ancient philosophers have elaborated on the
topic and provided some insight (Lynch, this volume; Pangle 2003), theoreticians
and researchers in the field of psychology have only been working on this issue for
the past three decades. For instance, it has been argued that friendship is related to
happiness because it fulfills a fundamental human need for social interaction (Bau%
meister and Leary 1995; Demir and Davidson 2013; Lyubomirsky 2007). Other
explanations primarily focus on specific provisions experienced in the friendship to
explain why this unique bond is related to or predictive of happiness. Specifically,
support received from the friend, intimacy in the relationship, spending time with
friends, and engaging in enjoyable activities with the friend have been proposed to
account#for#the#friendship%happiness#association#(Argyle#2001; Cooper et al. 1992;
Demir and Weitekamp 2007; Diener and Biswas-Diener 2008, Lyubomirsky 2007;
Reis 2001; Taylor 2010). Collectively, these arguments provide insight on the as%
sociation between friendship experiences and happiness.
!"#$%&'(#)*./+%0#01*+%&*,+))#%$''2 As addressed above, there are multiple dimen%
sions of friendships and each of them has been studied in relation to happiness among
young adults. To start with, a significant number of studies have shown a positive
association between the number of friends one claims to have and happiness across
different#ethnic#and#cultural#groups#(Berry#and#Hansen#1996; Burt 1987; Demir and
Weit ek am p 2007; Ellison 1990; Requena 1995; Taylor et al. 2001; Ying 1995). Yet,
the strength of association is typically low. Specifically, the correlation between
number of friends and happiness varies between " = 0.10 and 0.20 (see Lucas and
Dyrenforth 2006; Pinquart and Sörensen 2000 for meta-analytic reviews).
120 M.#Demir#et#al.
!"#$%&'(#)*./+3#01*+%&*,+))#%$''2 As for friendship quality, empirical studies have
consistently documented a positive association between friendship quality (overall
quality or single relationship provisions) and happiness among young adults across
cultures (Brannan et al. 2013; Cheng and Furnham 2003; Demir and Weitekamp
2007; Demir et al. 2007, 2011b, 2012, 2013a, 2013c; Lu 1995, 1999). The magni%
tude of the correlations across studies is often small to moderate ranging between
" = 0.20 and 0.40. An interesting finding in the literature is that the importance of
friendship quality for happiness varies by the degree of friendship closeness. A few
studies gathered relationship quality data for the participants’ best and two next
closest friends (Demir 2007; Demir and Özdemir 2010; Demir et al. 2007, 2011a).
Although the quality of every friendship was positively related to happiness, the
association was stronger for best friendship. Also, Demir et al. (2007) have found
that only best friendship quality emerged as a significant predictor when all friend%
ships competed for variance in happiness. Moreover, both studies found interactions
highlighting the importance of best friends. For example, the quality of other close
relationships did not matter for young adults’ happiness when the best friendship
was of low quality. Clearly, the benefits that might be accrued from less close friend%
ships are contingent on high quality relationship experiences with one’s best friend.
As Demir et al. (2013b, p. 863) aptly stated “… it is reasonable to suggest that it
might not be the number of friends one has, but the varying degrees of friendship
quality within one’s network of closest friends that matters most for happiness.”
!"#$%&'(#)*4+0#'5+60#7%*+%&*,+))#%$''2 A considerable number of studies focusing
on friendship satisfaction yielded a positive association between happiness across
cultures as well (Cooper et al. 1992; Diener and Diener 1995; Headey 1981; Lee
et al. 2002; Lyubomirsky et al. 2006; Michalos and Orlando 2006; Rojas 2006). The
strength of the correlation between satisfaction with friends and happiness varies
between " = 0.20 and 0.60. Overall, the available literature suggests that friendship
quality and relationship satisfaction are more important than quantity for happiness
among young adults.
!"#$%&'(#)*87%53#60*+%&*,+))#%$''2 Of the four indices of friendship, the associa%
tion of conflict with happiness among young adults has received the least amount of
attention from scholars. The findings from a limited number of studies addressing
the impact of conflict with friends are mixed. Some of the existing studies reported
a low to small negative correlation ranging from " = − 0.10 to 0.30 (Berry et al. 2000;
Demir 2010; Demir and Orthel 2011; Demir and Weitekamp 2007). Evidence also
exists suggesting that friendship conflict is similarly related to happiness among
women and men ( "' = − 0.28 and − 0.30, respectively) (Demir and Orthel 2011).
However, some other studies reported no significant association between friendship
conflict and happiness (Demir and Özdemir 2010; Demir et al. 2007). These incon%
sistent findings suggest that the relationship between friendship conflict (frequency,
resolution, management) and happiness should be examined in future research,
especially with a focus on potential moderating factors such as gender and culture.
!"#$%&'(#)94)$6#5#6*:;)$"#$%6$'* +%&* ,+))#%$''2 One promising line of research
that is growing in the literature focuses on specific friendship experiences such as
perceived autonomy support from friends (Deci et al. 2006) and perceived mat%
tering to friends (Demir et al. 2011b). This line of research is important because it
offers a broader, and perhaps a more theoretically coherent, perspective on friend%
ship as it relates to happiness. That is, although decades of research leave no doubt
that number of friends, satisfaction with friends, and friendship quality are related
to happiness (to varying degrees) for young adults across different cultures, these
studies do not tell much about how friendship specific experiences are related to
happiness. The greening and ripening of relationship science (Berscheid 1999;
Reis 2007) has undoubtedly helped friendship researchers as they move beyond the
investigation of friendship quality, quantity and their associations with happiness.
For instance, romantic relationship researchers have begun to propose and construct
measures that are "$3+0$& to relationship quality and satisfaction; however, they are
distinct in that they tap into more specific romantic relationship experiences (e.g.,
Gable et al. 2004). Recent work has begun to apply this same method to the study of
friendships (Demir et al. 2013). Additionally, self-determination theory (Deci and
Ryan 2000; Ryan and Deci 2000)#in#general#and#its#constructs#across#sub%theories#
has been studied in friendship context (e.g., Deci et al. 2006; Demir et al. 2011a).
Three recent studies deserve attention at this point. First, Ratelle et al. (2013)#
distinguished perceived autonomy support from multiple figures (parent, friends,
romantic partner) and found that support for autonomy from friends was positively
related to happiness (the composite score for happiness atypically included academic
life satisfaction). The authors also found that participants experienced the highest
level of happiness only when each relationship figure was perceived to be highly
autonomy supportive. It is important to note that this interesting finding could not
have been obtained had the authors not distinguished types of relationships. Second,
Demir et al. (2011a) have argued that perceived autonomy support from the friend
has the potential to promote relationship maintenance behaviors, which in turn is re%
lated to happiness. This mediation model was supported for the best and first closest
friendships among young adults using three different measures of happiness. Over%
all, these studies suggest that autonomy support from friends is related to happiness
through a mechanism that can be explained by friendship maintenance. Third, Demir
and Davidson (2013) showed that perceived mattering to the friend, perceived re%
sponses to one’s capitalization attempts, and satisfaction of basic needs in the friend%
ship were related to happiness. These findings generalized to both sexes and it was
shown that the above friendship experiences explained 19 and 27 % of the variance
in happiness among women and men, respectively. When the variables competed
for variance, needs satisfaction emerged as the most important predictor of happi%
ness in both groups. These studies clearly suggest that there is more to learn about
the friendship-happiness association, in addition to what we already know, based on
the satisfaction of various provisions (e.g., intimacy), relationship satisfaction, and
friendship quantity. Future research has the potential to develop a broader under%
standing of the topic by focusing on relationship specific experiences and feelings.
The current literature leaves no doubt that friendship is a robust and consis%
tent correlate of happiness. Our review suggests that the relationships of friendship
quality and satisfaction with happiness are stronger than friendship quantity. As
122 M.#Demir#et#al.
noted above, there is still more research that needs to be conducted before we can
firmly grasp the conflict-happiness association. However, it is gratifying that recent
research is moving beyond traditional correlates of friendship and happiness. As il%
lustrated in the aforementioned studies, the scope of friendship research has begun
to widen and encompass unique contributions of friendship-specific experiences as
they relate to happiness. It is essential to keep pace with these growing trends and
begin to discover how important friendship is to happiness when major correlates of
happiness and other close relationships of the young adults are taken into account.
We address this issue in the next section.
Our review of the literature suggests that friendship is a consistent correlate of
happiness among young adults. Yet, a few critical issues need to be presented and
highlighted before making strong statements about the importance of friendship
for happiness. These issues pertain to the methodological limitations that can be
identified within friendship and happiness studies, in addition to the role of friend%
ship in happiness when studied alongside robust correlates of happiness and other
significant bonds young adults maintain.
To start with, although various indices of friendship are consistently related to
happiness across studies and cultural groups, the correlations are generally small to
moderate. Thus, we dont believe that it would be appropriate to claim that friend%
ship is a major source of happiness (see Demir et al. 2013b) because doing so would
be an overstatement (Lucas and Dyrenforth 2006; Lucas et al. 2008). Additionally,
shared method variance is a common problem in the literature since most studies
rely on self-report measures of single informants. It has been argued that variables
that are measured using the same method, and through the same informants may
lead to inflation in the observed correlation estimates (DeVellis 2011). Thus, the
observed small to moderate association between friendship and happiness could
be partially affected by the shared method variance (Lucas et al. 2008). However,
studies that used other methods such as observational, experience sampling, and
longitudinal design have also reported a positive association between friendship
and#happiness#(Berry#and#Hansen#1996; Csikszentmihalyi and Hunter 2003; Grabill
and Kerns 2000; Larson 1990; Lu 1999). In sum, the small to moderate association
between friendship and happiness seems to be robust across various study methods.
Future multi-method and multi-informant research is needed though to provide fur%
ther support to this observation.
Second, convincing empirical evidence suggesting that friendship is a predic%
tor of happiness, above and beyond the major correlates of happiness, is needed
to highlight the importance of friendship for happiness. A well-established find%
ing# in# the# literature# is# that# personality# is# one# of# the# strongest# predictors# of# hap%
piness such that it explains as high as 50 % of the variance in happiness (Diener
et al. 1999; Lyubomirksy et al. 2005). Moreover, it is well-documented that various
personality characteristics such as extraversion and agreeableness are related to
friendship (Demir and Weitekamp 2007; Nelson et al. 2011; Selfhout et al. 2010). It
could be that personality might be the common cause of both friendship experiences
and happiness. Thus, the relationship between friendship experiences and happi%
ness might disappear once personality is taken into account. However, empirical
research among young adults in different cultures has shown that this is not the case.
Specifically, it has been shown that friendship experiences (e.g., quality) explained
additional variance in happiness above and beyond the influence of personality
among young adults in Taiwan, Turkey, and the U.S. (Demir and Doğan in#press;
Demir and Weitekamp 2007; Lu 1999). Overall, these findings across cultures sug%
gest that friendship is an important correlate of happiness among young adults; even
when major correlates of happiness are taken into account.
Third, the importance of friendship for happiness among young adults could
be tested more strictly when other significant relationships young adults main%
tain are assessed simultaneously. Although this issue has been more frequently
addressed in other age groups (e.g., Bertera 2005; Li and Cheng, this volume;
Okun and Keith 1998; Walen and Lachman 2000), a few studies among young
adults shed light on the topic. Demir (2010) examined the relative importance of
close relationships with mother, father, best friend, and romantic partner among
young adults with and without a romantic partner. Friendship quality was posi%
tively associated with happiness in both groups. Although friendship quality
was the most important predictor of happiness among single adults, it did not
emerge as a predictor of happiness for young adults involved in a romantic re%
lationship. Further, Brannan et al. (2013) studied the associations of perceived
social support from family and friends with happiness among college students
from Iran, Jordan, and the United States of America. Although perceived family
and friendship support were positively related to happiness across all cultures,
friendship support emerged as a predictor of happiness only for Jordanians and
Americans. These findings suggest that while friendship is cross-culturally
relevant, it is more important within some cultural contexts relative to others
when simultaneously assessed with support received from family. These stud%
ies among young adults suggest that the role and importance of friendship for
happiness might change depending on one’s relationship status and when the
quality of multiple close relationships is taken into account in different cultures.
To reiterate, how important is friendship to happiness? Although theoreti%
cians have argued that friendship is a major source of happiness (Argyle 2001;
Edwards and Klemmack 1973), our review suggests that this argument could
be debated. Certainly, friendship is a reliable and consistent correlate of happi%
ness among young adults even when taking major correlates of happiness into
account. Yet, the robust association of friendship with happiness might change
depending upon one’s relationship status and culture. Future research has the
potential to develop a stronger account of the friendship-happiness link. We
provide some theoretical and methodological directions to achieve this goal in
the next section.
124 M.#Demir#et#al.
Decades of empirical research leave no doubt that friendship is a source of happi%
ness and various friendship experiences are related to happiness to varying degrees.
Although this literature will continue to grow in the following years, there are a
number of theoretical and methodological issues that need to be addressed to fur%
ther the field. We believe that the issues raised below are not strictly relevant to
young adult friendship-happiness research, but would benefit friendship-happiness
research across various age groups.
It has become apparent over the years, that there is a need to develop reliable and
valid measurement strategies. There are a number of close social relationships that
might be mixed with friendship relations. Evidence suggests that people may con%
sider their relatives, siblings, or romantic partners as friends (Demir and Weitekamp
2007; Sheets and Lugar 2005). Also, it is possible to differentiate between friend%
ships as best friends, close friends, and ordinary friends. Young adults who were
provided with a definition of close friendship reported having fewer close friends
compared to their reports without a definition (Demir and Özdemir 2010; Reisman
1981). Thus, assessment procedures should include a clear definition of the targeted
friendship relationship. The observed associations that are obtained without a clear
definition may not provide clear evidence for reliable conclusions.
Related to the point above, it is essential that future empirical research distinguish
friendship from other relationships when investigating the association of social sup%
port or relationship satisfaction with happiness. Decades of theoretical work support%
ed with empirical research leave no doubt that relationships, satisfaction with them
(Baumeister and Leary 1995), and social support is related to happiness (e.g., Lakey
2013). Yet, recent empirical studies either do not specify the source of support, satis%
faction with support, or the researchers combine support received from multiple fig%
ures (e.g., family, friends) as they investigate the relationship between support and
happiness (Darbonne et al. 2013; Galinha et al. 2012; Herrero et al. 2011; Kong and
Yo u in#press; Siedlecki et al. in#press, Zhu et al., 2013). Although the findings from
this line of research are valuable, the findings convey the same well-accepted mes%
sage that relationships and perceived support do matter for happiness. Yet, it doesn’t
specify the role of friendships in happiness. More importantly, theoretical arguments
(e.g., Cantor 1979; Collins and Madsen 2006; Simons 1983–1984; see Li and Cheng
(this volume) for a review) and empirical research have clearly highlighted that dif%
ferent relationships serve different functions and play different roles in well-being
not only in young adulthood but also in different age groups (Antonucci et al. 2004;
Furman and Buhrmester 1992; Carbery and Buhrmester 1998; Demir 2010; Pinquart
and Sörensen 2000). Thus, we believe that a clear differentiation of friendship from
other relationships in future research would enhance our understanding of the posi%
tion of friendship in one’s social network as it is related to happiness.
A review of current literature shows that there has been little focus on cross-sex
friendships as most research has focused on same-sex friendship. This is a notable
limitation of the literature since individuals establish and maintain platonic cross-
sex friendships across the lifespan and this is especially common among young
adults#(Monsour#2002). Although developing and maintaining cross-sex friendships
might be difficult in different age groups, due to various adaptive and developmen%
tal tasks (Lewis et al., this volume), Procsal and her colleagues (Procsal et al., this
volume) have shown that cross-sex friendship is a reliable correlate of happiness in
different cultures. We believe that more research on the topic, especially cross-cul%
tural investigations, is needed to establish confidence in the findings that cross-sex
friendships are related to happiness, and to identify possible mediators and modera%
tors of this association.
Since the association of friendship with happiness is well-established in the lit%
erature, we believe that it is time researchers focus on the mediators and moderators
of this association (Demir et al. 2013; Demir et al. in press; Demir and Özdemir
2010). This call is consistent with Wilson (1967) who argued that there should be
less of an emphasis in the literature in which happiness is merely correlated with
variables. Understanding how, why, and when friendship is related to happiness is
necessary to develop a comprehensive understanding of the friendship-happiness
link. A few recent studies gave heed to these calls and have shown that satisfaction
of basic psychological needs in friendships (Demir and Özdemir 2010), perceived
mattering to friends (Demir et al. 2011b), and personal sense of uniqueness (Demir
et al. 2013c) accounted for the relationship between friendship quality and hap%
piness. More importantly, the mediating roles of needs satisfaction and perceived
mattering was observed across multiple friendships (best and the next two closest).
As this review showed, friendship is associated with happiness regardless of the
assessment of the constructs. Thus, the task before us is to keep investigating why
this is the case.
As for the moderators of the association, gender has been a commonly investi%
gated variable. Although gender might moderate the relationship between relation%
ship quality in intimate relationships and happiness (Saphire-Bernstein and Taylor
2013), studies focusing on friendship have shown that the associations of friendship
experiences (quality, perceived mattering) with happiness are similar across gender
(Demir and Davidson 2013; Demir et al. 2013b). On the other hand, past research
has shown that being in a romantic relationship and progress towards the resolu%
tion of developmental tasks such as identity formation moderated the friendship-
happiness link (Demir 2010; Demir et al. 2013b; Walen and Lachman 2000). For
instance, Demir (2010) has reported that friendship quality was not related to hap%
piness among emerging adults who had higher levels of conflict in their romantic
relationships. Further research is needed to examine other potential moderators,
such as culture, to understand if or when the relationship between friendship and
happiness may change.
logical research. The studies reviewed in this chapter overwhelmingly relied on
college students. Reliance on college students in research has been criticized mainly
because of the limited generalizability of findings to other age groups (Gordon et al.
1986; Henrich et al. 2009; McNemar 1946; Peterson 2001; Reynolds 2010; Sears
1986). Yet, recent studies suggest that college students are more similar than differ%
ent to other age groups and reliance on college students does not threaten the validity
126 M.#Demir#et#al.
of findings (Cooper et al. 2011; Wiecko 2010). Although this ongoing debate in the
literature is likely to continue in the following years, reliance on traditional college
students when studying the friendship-happiness association among young adults
might not represent a major concern because studies conducted with the college
population include the implicit assumption that they represent young adults. As
long as generalizations to other age groups are not a concern, reliance on college
students could be justified to some extent. Indeed, since the college students repre%
sent a worthy population of empirical study there are specific journals dedicated to
the understanding of college students’ experiences and large-scale studies investi%
gating the mental health of this population (e.g., Castillo and Schwartz 2013). Yet,
not every young adult in the United States of America (Stratton 2014)#and#in#other#
cultures (e.g., Nelson et al. 2013) goes to college. This fact challenges the implicit
assumption of studies conducted with college students such that findings might be
generalized#to# non%college%attending#young#adults#(Tanner#2006). Although a few
studies have shown that college students are similar to their non-college-attending
peers (e.g., Blanco et al. 2008), no study, to the best of our knowledge, investigated
the friendship-happiness association in these two groups. Thus, it remains to be seen
whether the findings obtained with college students generalize to the young adults
who are not in college.
Although the issues raised above are important, another critical, yet understudied
phenomenon within friendship literature, is the issue of volunteer bias. Considering
that college students are often relied upon as participants in this research domain,
it is essential to examine what (if anything) sets those who are interested in study
participation apart from those who are uninterested. A growing body of research has
documented the potential pitfalls of utilizing research volunteers in non-friendship
related areas of study. Findings from various disciplines have shown that volun%
teers often times significantly differ from non volunteers, suggesting that there is
a self-selection process inherent to research which relies on volunteer convenience
samples (Berman et al. 1998; Strassberg and Lowe 1995; Weiderman 1999). This
phenomenon has been labeled as volunteer bias (Heiman 2002).
While there has been little attention paid to this potential confound within friend%
ship and happiness literature, some preliminary studies have sought to identify
whether this is a valid concern within the field. For example, Orthel and Demir
(2011) asked participants with a same-sex best friend (SSBF) their willingness to
participate in a research study on same-sex friendship. Following this initial ques%
tion, regardless of their willingness and without their knowledge about the content,
participants were then provided with well-established measures tapping into friend%
ship and happiness constructs. Findings revealed that men were less willing than
women to participate in friendship research, a finding consistent with past research
(Lewis et al. 1989). Results also revealed interesting patterns for volunteers and
non-volunteers. Volunteers, compared to non-volunteers, reported higher levels of
relationship quality and friendship specific experiences (e.g., autonomy support)
with moderate effect sizes. Although the groups did not differ from each other on
happiness, the strength of the correlations between friendship variables and happi%
ness were significantly stronger for non-volunteers when compared to volunteers
across men and women. These findings pose a potential threat to the validity of
the findings within young adult friendship research. Specifically, it could be that
we are studying college students who have better friendships. Yet, the friendship-
happiness association is stronger in the non-volunteer group. This pattern suggests
the possibility that reliance on volunteers and their restricted range of data might
be minimizing the magnitude of the relationship that does exist between friend%
ship quality and happiness. As we continue to develop our understanding of the
relationship between happiness and friendship, it is encouraged that researchers be
cognizant of the potential implications of convenience sampling and cautious about
making generalizations.
For#researchers# seeking# to#address#the#significance# of# friendship#for#happiness#
across the lifespan, it is important to note that views of adulthood have begun to
shift towards incorporating a new stage, emerging adulthood (Arnett 2006). It has
been proposed that the period of the human lifespan encompassing the late teens to
the late 20’s is inclusive of unique social experiences (Arnett 2000). Although this
age group has been recognized and a variety of close relationships during this age
group has been studied, few studies focused on friendship among emerging adults
and investigated the friendship-happiness association in this age group (Barry and
Madsen#2010; Collins and van Dulmen 2006; Demir 2010; Lefkowitz et al. 2004).
That is the reason why the focus of of this chapter was on young adults.
Researchers have characterized emerging adulthood as a period of identity ex%
ploration. Thus, while individuals experience what the world has to offer in ways of
work, love, friendship and education, they are likely to experience instability within
these domains just the same (Arnett and Tanner 2006). One could question wheth%
er this trend in instability generalizes to one’s relationships as well. Are emerging
adult friendship needs and experiences distinct relative to other developmental pe%
riods? Do friendship experiences have a unique way of influencing happiness dur%
ing emerging adulthood? At this time, there are more questions than answers with
respect to how friendship experiences may or may not be unique during this stage of
development. Oswald and Clark (2003) showed that during the transition from high
school to college, many emerging adults begin to experience decreased satisfac%
tion, commitment and investment with best friendships from high school. However,
maintenance of best friendships has been shown to have a sort of protective effect
from loneliness (Oswald and Clark 2003). These findings speak to the challenges
that are specific to friendship in emerging adulthood, as well as one of the functions
friendship can serve during this period. Future research should seek to grow our
understanding of friendship and its contributions to happiness for emerging adults.
Additionally, researchers should be careful to distinguish emerging adulthood as
a stage that is distinct from adolescence and young adulthood (Arnett and Tanner
2006). This will undoubtedly be a challenge for researchers because of the possibil%
ity that not every college student is or feels like an emerging adult (Kins and Beyers
2010). We believe that assessment of the achievement of adulthood criteria (Nelson
and#Barry#2005) would be useful when investigating the friendship-happiness asso%
ciation. This approach has the potential to differentiate emerging adults from young
adults. Although this practice requires more work before assessing the friendship
128 M.#Demir#et#al.
experiences of the participants, it is needed and essential if we are to develop a clear
understanding of the friendship-happiness association among emerging and young
The final, but perhaps the most important issue surrounding the friendship-
happiness association, is the question of causality. Some scholars have argued that
friendship is an important source of happiness suggesting a causal link (Argyle
2001; Edwards and Klemmack 1973). Argyle (2001) even proclaimed that social
relationships are the “greatest single cause” of happiness. Nevertheless, this argu%
ment is not supported by evidence yet. Most studies on friendship-happiness as%
sociation are correlational. Correlational studies cannot provide evidence regarding
the direction of effect. Moreover, there is also evidence suggesting that changes
in well-being influences the number of friends, rather than the other way around,
among non-married elderly women (Adams 1988). In sum, there is need for more
research to test the direction of effect between friendship and happiness and the as%
sumption of causality.
The#question# of# directionality# and#causal#link#could# be# addressed# using#differ%
ent research methods. Longitudinal studies may help testing hypotheses regarding
whether changes in friendship experiences are related to changes in happiness or
the other way around. Longitudinal data is also best suited to test mediating mecha%
nisms that may explain why and how friendship is linked to happiness (MacKinnon
et al. 2010). Such studies need to measure multiple aspects of friendship and hap%
piness repeatedly over time, allowing sufficient time to pass between measurement
intervals to observe changes in both friendships and happiness. Researchers may
test direction of effects using cross-lagged models (Finkel 1995)#or#parallel#process#
growth models (Duncan et al. 2006). In addition, researchers may focus on examin%
ing changes in social networks over time using another state-of-the-art method that
can analyze social networks such as SIENA (Simulation Investigation for Empirical
Network Analysis; Ripley et al. 2012). Longitudinal peer nomination data may be
analyzed using network analysis techniques to answer whether friendship forma%
tions over time increase happiness, or whether happiness is predictive of friendship
formations over time. Peer nomination technique is often used to collect data from
school age children and adolescents. However, this technique could also be applied
to college and workplace samples. In sum, state-of-the-art data analysis methods for
longitudinal design could further our understanding of the link between friendship
and happiness, the processes that may explain this association, and eloquently ad%
dress some of the problems inherent in the current literature (e.g., Lucas et al. 2008).
Despite its strengths, longitudinal research design does have limitations when
trying to infer causality. Causal inference requires meeting three different condi%
tions (Shadish et al. 2002). Applying these conditions to the friendship-happiness
link, researchers should demonstrate that (1) changes in friendship should precede
the changes in happiness; (2) changes in friendship is statistically significantly re%
lated to the changes in happiness; and (3) there is no other plausible explanation to
changes in happiness other than the changes in friendship. Longitudinal design may
provide test of the first two conditions. However, all these conditions could only be
met by well-conducted experimental research designs (Shadish et al. 2002). Thus,
prevention trials may provide a new avenue to test the causal link between friend%
ship and happiness. Including carefully designed measurements into the evaluation
of the effectiveness of prevention programs targeting social skills and friendship
relations may further our understanding of the association between friendship and
Friendship is a precious and cherished relationship for young adults, especially
among those who are single and in college. Decades of empirical research leave
no doubt that friendship is a reliable correlate of happiness in this age group. The
associations of indices of friendship with happiness are small to moderate in size,
but consistent across gender, ethnic, and cultural groups. Although significant sci%
entific progress has been observed in the last decade, future research investigating
the friendship-happiness association among young adults could be enhanced by ad%
dressing a number of theoretical and methodological considerations. For instance,
by providing clear definitions of what constitutes a friend prior to measuring friend%
ship experiences. In addition, through incorporating multi-method approaches (e.g.
longitudinal, experimental, quasi-experimental) we can undoubtedly enhance con%
directionality and causality within the study of friendship and happiness. Address%
ing these challenges has the potential to substantially advance theory and research.
It is well-established that friendship is related to happiness. The task before us is
to keep researching why and when this is the case, by taking the limitations of the
current literature into account.
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... The values that students use while expressing friendship are honesty, sincerity, trust, camaraderie, sharing, love, compassion, devotion, fairness, understanding, brotherhood, success, confidentiality, being open, being kind, keeping the word, loyalty, respect, tolerance, goodness, being truthful, being unselfish, not lying, being smiling, being beautiful, being self-seeking, getting along, not being rude, not taking sides, freedom, bonding, being polite, not being rude, not disdaining. When the literature is examined, friendship is often expressed as a set of unplanned personal relationships that are voluntary, meet social and emotional needs, include mutual help and love (Demir, et al., 2015). Friends are important individuals in reassuring each other, offering suggestions, sharing important problems in confidence, protecting them, creating a continuous togetherness, and getting used to situations of tension (İnanç, et al., 2007). ...
... moderno e occidentale tendente all'individualismo (libertà, studio), ma che, in maniera ambivalente, porta dentro di sé i germogli rivoluzionari e le tensioni trasformative di nuove sensibilità-necessità che gridano al superamento della crisi ecologica attuale e al rinnovo di una nuova fraternità (Morin, 2020).In particolare, il valore dell'amicizia, del rapporto con i pari identifica un contesto relazionale di vita di elevata importanza per i giovani. A tal proposito, sono diverse le ricerche che evidenziano l'importanza del legame con i pari per la felicità di questi giovani, che talvolta sembra raggiungere l'importanza attribuita alla famiglia (Demir et al., 2015). Quest'ultima e i valori ad essa collegati, come la fedeltà, rimangono invece un aspetto trasversale e costante tra le generazioni: qualche cosa in cui riconoscersi e a cui guardare, trovando sicurezza, soprattutto nei momenti di forte incertezza e stressanti, come quelli della pandemia, come risulta chiaramente dall'analisi delle risposte aperte; la famiglia, tradizionalmente importante per genitori e nonni, si mantiene come una dimensione di rilevante importanza per i giovani italiani. ...
... As we go through life, we build many relationships with various people such as family, friends, co-workers, and partners. Among these relationships, we spend much time with our friends, and further having friends is important for our development and life satisfaction (Demir et al. 2015). Especially college students spend a tremendous amount of their time with their friends as on average they spend 86 h a week with their friends while they spend only 15 h a week in class (McCabe 2016). ...
Phubbing is the act of snubbing someone during face-to-face interactions by using smartphones instead of paying attention to them. Although studies have examined phubbing in many different relationships, little is known about friend phubbing (Fphubbing). The present study examines which individual factors including indicators of mental health (i.e. depression and social anxiety) and personality traits (agreeableness and neuroticism) are significantly associated with Fphubbing, and how such behaviour is relevant to relational satisfaction with friends. Also, this study investigates the mediating role of Fphubbing between the proposed predictors and friendship satisfaction. Results showed that those with higher levels of depression, social anxiety, and neuroticism were significantly related to greater friend phubbing while agreeableness was negatively related to friend phubbing. In addition, greater Fphubbing led to lower levels of friendship satisfaction. Interestingly, Fphubbing mediated the relationships between each predictor of friend phubbing and friendship satisfaction. This study provides a theoretical framework to understand Fphubbing and contributes to filling a knowledge gap of phubbing in different relationship types.
... Interestingly, we did not find a significant unique environmental correlation between well-being and satisfaction with friendships, suggesting that the association between those two traits is non-causal, at least in adolescence. While multiple studies identify an association between well-being and friendship quality/satisfaction [38,42], these studies did not yet take into account the potential role of genetic factors. Based on what we find here, the most likely explanation for this association is that those who consider themselves to be satisfied with their lives are more likely to also consider themselves satisfied with their friendships due to them having a general (genetic) predisposition for positive ratings of life domains. ...
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Socio-environmental factors play an important role in adolescent well-being, but potential genetic contributions to these associations are rarely assessed. To address this gap in the literature, associations between well-being and family conflict and functioning, number of friends, friendship importance and satisfaction, and leisure time variables were studied in N = ~ 4700 twin pairs from the Netherlands Twin Register, us ing generalized estimating equations and twin-difference scores. When twin-difference scores indicated a role for genetic factors, we used bivariate genetic models to quantify genetic and environmental contributions to these associations. We identify significant associations between well-being and family functioning, family conflict, different leisure time activities, number of friends, and satisfaction with friendships. Additionally, we find evidence for large (73–91%) genetic influence on the associations between well-being and family conflict and functioning, leisure time sport/scouting clubs, and satisfaction with friendships. Finally, findings support the hypothesis of a causal association between well-being and family conflict and functioning. These findings have important implications for research into the social correlates of well-being in adolescence, as not taking genetic factors into account leads to overestimations of the influence of identified correlates and consequently to recommendations of these correlates as intervention targets.
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The quality of individuals’ social relationships consistently predicts greater well-being. But little is known about the relative importance of different relationship types for life satisfaction, including the relative importance of friendships compared to other types of relationships. Some have theorized that one intimate relationship is all you need. However, romantic partners, family, and friends may contribute uniquely or interactively to well-being. The current study assessed life satisfaction and relationship satisfaction in survey data collected from a large, diverse sample of respondents. Satisfaction with each type of relationship was significantly and independently associated with life satisfaction, over and above other variables in the model. Friendship (not family) interacted with intimate relationships: when respondents were highly satisfied with their intimate relationships, they were happy with their lives regardless of friendship quality. But when they were unhappy with their intimate relationships, they were only happy with their lives if they had good friends.
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Friendship may help to bridge differences between people, such as between age-diverse employees. Oftentimes, age diversity in employee interactions cultivates interpersonal tensions. Age-diverse workplace friendship—a relationship between coworkers of different ages, who like each other and who are engaged in a balanced social exchange—may help to overcome these interpersonal tensions because having something in common can de-escalate age-related difficulties and reduce negative feelings between diverse individuals. Despite the relevance of the topic, literature focusing on age-diverse workplace friendship is rare. To address this gap and direct future research, we aim to integrate research on related topics such as workplace friendship and (age) diversity at work into a systematic literature review. Concentrating primarily on the formation and maintenance of age-diverse workplace friendship, we identified similarity-attraction theory, social identity theory, and socioemotional selectivity theory as the three dominant theories referenced in the literature and utilize them to embed and connect our findings into existing theory. More specifically, we review and summarize the findings of our systematic literature review into an integrated framework depicting the antecedents, formation and maintenance processes, and outcomes of age-diverse workplace friendship. We discuss the theoretical and practical implications of our findings and point out directions for future research.
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Few studies have been carried out on emerging adults’ friendships and on their developmental roots. Research suggests that in adolescence, both attachment to parents and attachment to peers play a role in future socio-emotional development. The aim of the present study was to compare attachment in these two types of relationships in adolescence according to gender and test whether they respectively predicted the perception of best friendship in early adulthood. A sample of 83 participants (49 girls) was seen in early adolescence (M = 13.66 years, SD = 0.64) and 7 years later (mean age = 21.15 years, SD = 0.83). At T1, participants completed the Inventory of Parent and Peer Attachment, which measures attachment using three subscales (communication, alienation and trust) and one global security score. At T2, they completed the McGill Friendship Questionnaire. Results show that in adolescence, boys report higher security with parents compared to peers (mainly due to better communication), unlike girls who obtain higher scores with peers. Longitudinal findings reveal that alienation in the relation with parents is what best predicts friendship quality in early adulthood. These findings underline the specific internal working models at play in socio-emotional development and the way gender differences evolve from adolescence to early adulthood.
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When I began thinking about writing this introduction, about what readers might want to know concerning the history, aims, scope and structure of the first ever Encyclopedia of Quality of Life and Well-Being Research (EQOLWR), it occurred to me almost immediately that I had never read the introduction of any encyclopedia.
Chapter Data, Program Inputs and Outputs for all LGM Examples in the textbook "An Introduction to Latent Variable Growth Curve Modeling: Concepts, Issues, and Applications, Second Edition". Model specifications are included providing program syntax for Amos, EQS, LISREL, and Mplus software programs. The files are arranged by chapter and include syntax, data, and output files for all examples a particular software program is capable of estimating. The first three chapters (specification of the LGM, LGM and repeated measures ANOVA, and multivariate representations of growth and development) cover the development of the LGM. These are followed by three chapters involving multiple group issues and extensions (analyzing growth in multiple populations, accelerated designs, and multilevel longitudinal approaches), and followed by the chapter on growth mixture modeling, which addresses multiple-group issues from a latent class perspective. The remainder of the book covers 'special topics' (chapters on interrupted time series approaches to LGM analyses, growth modeling with ordered categorical outcomes, Missing data models, a latent variable framework for LGM power analyses and Monte Carlo estimation, and latent growth interaction models). The zipfile is quite large (1MB) since it contains all files for the various software programs.
The higher education system in the USA has been the envy of the world for decades. Yet recently, graduation rates in the USA have lagged behind those in other nations, raising concerns that the USA may not be able to maintain its competitive edge in human capital investment. Economic theory suggests that individuals enroll in college when the marginal benefit associated with enrollment exceeds the marginal cost. This chapter offers a detailed review of the factors influencing enrollment in a simple human capital model: the employment horizon, the college wage premium, the opportunity and net tuition costs, and the discount/interest rate. After a brief discussion of heterogeneity, a more complex model that relaxes many of the assumptions inherent in the simple model is presented. This model incorporates unemployment, benefits packages, taxes, and imperfect capital markets. The chapter concludes with a brief review of dynamic factors and supply-side constraints.
To have friends is considered to be a normal and desirable aspect of a modern American social life. The mass media is filled with images of all types of people working and relaxing with one or more friends. Empirical studies support this image of friends as being an important part of the normal social life. In one such study, Lowenthal, Thurnher, and Chiriboga (1975) did an extensive survey of the friendship patterns of adults in the United States. They found that, on the average, people report having approximately six relationships that can be called friendships. However, this number varies in predictable ways with life stage. For example, newlyweds have the highest number of reported friends (eight). This is higher than the average five reported by high-schoolers, the average five reported by middle-age married persons, or the average six reported by persons about to retire. Even with these fluctuations it is clear that Americans typically have a substantial number of friends over the life cycle.