two assignments due tmm

Intensity of Smiling in Facebook Photos Predicts Future Life Satisfaction

J. Patrick Seder1 and Shigehiro Oishi1

Abstract Does the extent to which people are smiling in their Facebook photos predict future life satisfaction? In two longitudinal studies, the authors showed that smile intensity coded from a single Facebook profile photograph from male and female participants’ first semester at college was a robust predictor of self-reported life satisfaction 3.5 years later—as they were about to graduate from college. Controlling for first-semester life satisfaction, the authors also determined that smile intensity was a unique predictor of changes in life satisfaction over time. In addition, the authors demonstrated that the results were not due to extraversion or to sex differences in smile intensity. Finally, the authors showed that participants who exhibited a more intense smile in their Face- book photo had better social relationships during their first semester at college and that the association between smile intensity and life satisfaction 3.5 years later was partially mediated by first-semester social relationships satisfaction.

Keywords subjective well-being, facial expression, nonverbal communication, relationships, facebook

The expression of positive affect captured in a photograph can

convey surprisingly rich information about people’s long-term

well-being. Harker and Keltner (2001) garnered much atten-

tion, for example, by showing that the intensity with which

female students were smiling in their college graduation year-

book photos (in 1958 and 1960) was correlated with self-

reported life satisfaction up to 30 years later. More recently,

Hertenstein, Hansel, Butts, and Hile (2009) found that intensity

of smiling in photos taken before the age of 22 was negatively

correlated with likelihood of divorce later in life. Abel and

Kruger (2010) also coded smile intensity in archival photo-

graphs of early career professional baseball players; those who

displayed an intense smile in their photos lived an average of

7 years longer than players who displayed minimal smiling.

Although such findings are highly intriguing, at this point,

it is still unclear why smile intensity in photographs predicts

future well-being. Further, in the decade that has passed since

their novel findings were published, Harker and Keltner’s

(2001) work predicting future self-reported life satisfaction

from smile intensity in (formal) photographs has yet to be

replicated or extended—even in shorter duration studies. In

fact, the only published attempt (Freese, Meland, & Irwin,

2007) failed to replicate the findings using high school gra-

duation yearbook photos. Given that Harker and Keltner’s

participants were female, questions also remain as to whether

their findings would be likely to replicate with male partici-

pants. Past research has shown, for example, that women tend

to smile more intensely than men (e.g., LaFrance, Hecht, &

Paluck, 2003).

We conducted the present research with two main goals in

mind. First, we aimed to examine whether the intensity of smil-

ing in men and women’s Facebook profile photos (which are

typically informal in pose) would predict future subjective

well-being—just as formal photos did in the previous research.

Second, and more importantly, we sought to take steps toward

clarifying why intensity of smiling in a photo at one point in

time might predict later subjective well-being. One possibility

is that smile intensity predicts life satisfaction because it

reflects the relatively stable personality trait of extraversion,

which is associated with both life satisfaction (Diener, Oishi,

& Lucas, 2003) and smiling (Naumann, Vazire, Rentfrow, &

Gosling, 2009). That is, extraversion might be the third variable

responsible for the association between smile intensity and

long-term life satisfaction. A second possibility is that people

who smile more intensely in their ‘‘public’’ photos (e.g., on

Facebook) may have more satisfying social relationships. Past

research has shown, for example, that smiling in a photo signals

interpersonal warmth, friendliness, and other desirable attri-

butes (Back et al., 2010; Naumann et al., 2009; Vazire & Gosl-

ing, 2004). People who display more positive affect may

therefore have an easier time of forming and maintaining

1 Department of Psychology, University of Virginia, Charlottesville, VA, USA

Corresponding Author:

J. Patrick Seder, Department of Psychology, University of Virginia, P.O. Box

400400, Charlottesville, VA 22904, USA

Email: [email protected]

Social Psychological and Personality Science 3(4) 407-413 ª The Author(s) 2012 Reprints and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/1948550611424968 http://spps.sagepub.com

satisfying social relationships. Because positive relationships

are also associated with life satisfaction (Diener & Seligman,

2002), intensity of smiling in publicly shared photographs

might lead to higher levels of life satisfaction via positive

social relationships.

To our knowledge, the current research is the first to test

these possible mechanisms (i.e., personality and social relation-

ships) linking smile intensity at one point in time with future

self-reported life satisfaction. In order to do this, we conducted

two longitudinal studies in which we tracked female and male

students beginning in their first semester of college until their

final semester—just before graduation. We coded the intensity

with which participants were smiling in their first-semester

Facebook profile photos and used this variable to predict

self-reported life satisfaction in the final semester at college

3.5 years later.

Study 1

Method

Participants

Participants were required to be first-year students (in fall

2005) in the participant pool at University of Virginia and to

have at least one Facebook profile photograph that could be

retrieved and coded for smile intensity. A total of 92 partici-

pants (35 male) met these criteria and were invited to complete

the follow-up measures given 3.5 years later (in their last seme-

ster at college). The final sample consisted of 48 participants

(20 male). We compared those who completed the follow-up

study with those who dropped out after Time 2; we found no

differences in life satisfaction, extraversion, or social relation-

ships satisfaction, |t|s < .77, ps > .44. 1

Materials

Time 1 (beginning of first semester at college). Participants

completed an assessment of extraversion (Brody &

Ehrlinchman, 1997) as part of the departmental pretest-

ing session.

Time 2 (end of first semester). Participants completed the

Satisfaction with Life Scale (SWLS; Diener, Emmons,

Larsen, & Griffin, 1985). They also rated social relation-

ships satisfaction in the following domains: friendships,

family relationships, and social relationships in general

(1 ¼ extremely dissatisfied to 7 ¼ extremely satisfied). Time 3 (end of final semester; Spring 2009). Participants

again completed the SWLS.

Procedure for coding the expression of positive affect in photographs. After participants completed the Time 2 measures, we retrieved and saved their most recent Facebook profile

photo—which is the largest and most ‘‘public’’ photo displayed

on the site. In the majority of cases, participants’ photos had

been made public on Facebook prior to completion of the Time

2 self-report measures. Only photos containing a clear (and

‘‘non-jokey’’) shot of the participants’ face were deemed suit-

able for coding. 2

In the small number of cases in which the cur-

rent profile photo could not be coded, we used the next (most

recent) codable profile photo (which are archived by Facebook

in order of upload date).

Because we wished to replicate and extend their past find-

ings, we adopted the coding procedure used by Harker and

Keltner (2001). This involves coding the intensity of action

in the two muscle action units (AUs) associated with smiling.

The first, AU6 (orbicularis oculi), elicits raised cheeks and

squinting. The second, AU12 (zygomatic major), causes smiling

via raising the corners of the mouth. Each AU was coded using

an intensity scale that ranged from 1 (minimal) to 5 (maximum).

The two scores were added together in order to create a contin-

uous score for smile intensity (which could range from 2 to 10).

Photos were coded by the first author and two other trained

research assistants (a¼ .88). We calculated the final smile inten- sity score by taking the mean of the three coders’ ratings.

Results and Discussion

In line with past research on sex differences in smiling, women

(M ¼ 8.41, SD ¼ 1.28) did smile more intensely than men (M ¼ 7.04, SD ¼ 2.27), t(46) ¼ 2.68, p ¼ .01, d ¼ .74. However, sex did not moderate any of the analyses reported here. All results

are thus reported using the full coed sample.

Table 1 shows the descriptive statistics and the correlations

among the key variables. As seen in Table 1, participants who

Table 1. Descriptive Statistics and Correlations Among Key Variables in Study 1

Smile LS1 LS2 Extra Social Relationships

Satisfaction M (SD) a

Smile intensity — .34* .47** .16 .25*** 7.87 (1.84) .88 Life satisfaction 1 — .57** .53** .68** 26.05 (5.60) .87 Life satisfaction 2 — .23 .34* 26.20 (6.20) .89 Extraversion — .38** 3.73 (0.85) .86 Social relationships satisfaction — 5.64 (1.03) .76

***p < .10. *p < .05. **p < .01. Smile intensity, extraversion, life satisfaction 1 (LS1), and social relationships satisfaction were measured in the first semester of college. Life satisfaction 2 (LS2) was assessed 3.5 years later (final semester of college). Smile intensity could range from 2 to 10. Life satisfaction could range from 5 to 35. Extraversion could range from 1 to 5. Social relationships satisfaction could range from 1 to 7.

408 Social Psychological and Personality Science 3(4)

displayed a more intense smile in their first-semester Facebook

profile photo were also more satisfied with their lives during

that semester than those who displayed a less intense smile.

More importantly, smile intensity predicted self-reported life

satisfaction at the end of college—3.5 years later, r(46) ¼ .47, p < .01. We were, in other words, able to replicate the basic

predictive relationship reported by Harker and Keltner (2001)

in their all-female samples.

We also examined whether changes in self-reported life

satisfaction from the first year to the fourth year would be pre-

dicted by smile intensity. This was important to assess in part

because the past research reported only simple correlations

between smile intensity and self-reported life satisfaction at

each future time point. Controlling for first-semester life satis-

faction, smile intensity in the Facebook profile photos still pre-

dicted life satisfaction measured 3.5 years later, b ¼ .32, t(45) ¼ 2.60, p < .05, DR2 ¼ .089, f 2 ¼ .098. Thus, we were able to extend the past research in a second novel way by determining

that intensity of smiling in the first-semester profile photo was

also a unique predictor of changes in self-reported life satisfac-

tion over time.

Next, we tested whether the longitudinal association

between smile intensity and life satisfaction would be due to

the third variable of extraversion. As seen in Table 1, smile

intensity in the profile photos was not significantly correlated

with self-reported extraversion. If the longitudinal association

between first-semester smile intensity and final-semester life

satisfaction was due to extraversion, then inclusion of extraver-

sion in the regression model should reduce the association to

zero. However, smile intensity in the Facebook profile photos

remained a significant predictor of life satisfaction at the end

of college, controlling for extraversion, b ¼ .40, t(40) ¼ 2.81, p < .01, DR2 ¼ .156, f 2 ¼ .185. In short, we found no evi- dence for the extraversion-as-third-variable account of the

longitudinal association between smile intensity and later life

satisfaction.

Finally, we examined a second possible mechanism, namely,

whether smile intensity in the Facebook profile photos would

predict the quality of participants’ end-of-first-semester social

relationships satisfaction, which in turn would predict life satis-

faction 3.5 years later. As seen in Table 1, smile intensity did

predict satisfaction with social relationships. In addition, satis-

faction with social relationships was positively associated with

final-semester life satisfaction. We next tested whether satisfac-

tion with social relationships would mediate the longitudinal

link between first-semester smile intensity and life satisfaction

at the end of college. To do this, we used Mplus 4.21’s (Muthén

& Muthén, 2007) bias-corrected bootstrap method (number of

bootstrap set to 5,000, as recommended by Preacher & Hayes,

2008). The model indicated the presence of partial mediation,

indirect effect ¼ .10 (95% confidence interval [CI] ¼ [.02, .42]), z ¼ 1.66, p ¼ .10. Thus, first-semester social relationships satisfaction did appear to be an important link between smile

intensity and future self-reported life satisfaction.

In sum, our longitudinal study using the Facebook profile

photos of college students replicated—for the first time and

with contemporary male and female participants—Harker and

Keltner’s (2001) earlier findings which used the formal gradua-

tion yearbook photos of female college students (class of 1958

and 1960) to predict future self-reported life satisfaction. One

issue not addressed in the past research was that the longitudi-

nal association between smile intensity at one point and life

satisfaction at a later time might be explained by the possibility

that both variables are indicators of a general latent factor of

well-being. In order to eliminate this general well-being

account, we felt that it was critical to determine whether the

longitudinal association would exist even when life satisfaction

at the first assessment is statistically controlled. In the current

research, we demonstrated for the first time that smile intensity

in the public photo did indeed predict future life satisfaction

even after controlling for life satisfaction reported in the first

semester at college. In other words, first-semester smile inten-

sity predicted not only the level of life satisfaction 3.5 years

later but also the change in participants’ life satisfaction from

the first to the final semester at college.

In addition, we found no evidence that extraversion (which

is typically correlated with well-being) was responsible for the

longitudinal association between smile intensity in the photos

and future life satisfaction. Finally, we found preliminary sup-

port for the idea that participants who exhibited a more intense

smile in their Facebook profile photo had better social relation-

ships during their first semester at college, and that the associ-

ation between smile intensity and life satisfaction 3.5 years

later was partially mediated by first-semester social relation-

ships satisfaction.

When interpreting the present findings, however, it is impor-

tant to acknowledge several limitations. First, although the par-

ticipants in our study appeared to be rather typical of their

university cohort, the size of our final sample was modest. Sec-

ond, our participants had the distinction of being a somewhat

unique group—they were members of the very first cohort of

college freshmen (in fall 2005) to make use of Facebook when

it became available at most U.S. colleges. Why might that mat-

ter? By the following calendar year, the number of Facebook

users more than doubled (from 5.5 million to in excess of 12

million); during that time, the site also became available to

non-academic users, and many new features intended to

increase ease of content sharing were added (Facebook.com,

2010). Thus, because the participants in Study 1 were early

adopters of Facebook, it is plausible that they could be quite

different from subsequent Facebook users in terms of display

norms in their profile photos or other measured or unmeasured

variables. Combined with the fact that this study was (to our

knowledge) the first to successfully replicate and expand upon

Harker and Keltner’s (2001) groundbreaking work, we felt that

it was important to replicate these findings in another sample.

Additionally, the lack of correlation between smile intensity

and extraversion seemed a bit surprising, given the documented

positive relationship between smiling and perceived extraver-

sion in past research (Naumann et al., 2009). 3

Thus, this matter

also appeared to warrant further investigation. To address each

of these concerns, we conducted a second longitudinal study

Seder and Oishi 409

with a cohort of male and female university students who began

in fall 2006, when Facebook enrollment and usage had greatly

increased.

Study 2

Method

Participants

Participants were required to be first-year students in the parti-

cipant pool at University of Virginia (in Fall 2006) and to have

at least one Facebook profile photograph that could be

retrieved and coded for smile intensity. A total of 49 partici-

pants (17 male) met these criteria and were invited to complete

the follow-up measures given 3.5 years later (when they were

in their last semester at college). 4

The final sample consisted

of 36 participants (13 male). As with Study 1, no differences

were found for life satisfaction, extraversion, or social relation-

ships satisfaction between those who completed all three

phases of the study and those who dropped out after Time 2,

|t|s < .701, ps > .489. 5

Procedure and Materials

The procedure and materials were largely identical to those

used for Study 1. However, participants in Study 2 completed

a different measure of extraversion (Gosling, Rentfrow, &

Swann, 2003; possible range of 1–6) at Time 1 (the

department-wide pretest). The procedures used for coding the

photographs were identical to those used in Study 1. Once

again, interrater reliability was high (a ¼ .96).

Results and Discussion

As in Study 1, women (M ¼ 7.86, SD ¼ 2.13) smiled more intensely than men (M ¼ 6.10, SD ¼ 2.80), t(34) ¼ 2.12, p ¼ .042, d ¼ .71. For a second time, however, sex did not moderate any of our analyses. All results are therefore reported

using the full coed sample.

Table 2 shows the descriptive statistics and the correlations

among the key variables. Replicating Study 1, participants who

displayed a more intense smile in their first-semester Facebook

profile photo were more satisfied with their lives during that

first semester. More importantly, they were also more satisfied

with their lives in their final semester at college, r(34) ¼ .57, p < .01. Thus, we again replicated the basic Harker and Keltner

effect. In addition, smile intensity predicted self-reported life

satisfaction 3.5 years later even when controlling for first-

semester life satisfaction, b ¼ .35, t(33) ¼ 3.02, p < .01, DR2 ¼ .104, f 2 ¼ .116. For a second time, then, we were able to show that smile intensity was also a unique predictor of

changes in self-reported life satisfaction over time.

In contrast with the results of Study 1, smile intensity was

significantly correlated with extraversion (see Table 2). How-

ever, first-semester smile intensity still predicted life satisfac-

tion in the final semester of college controlling for

extraversion, b ¼ .44, t(23) ¼ 2.83, p < .01, DR2 ¼ .167, f

2 ¼ .200. Thus, we were again able to conclude—and with greater confidence given the use of a different measure of

extraversion—that the longitudinal association between smile

intensity and life satisfaction 3.5 years later was not due to the

third variable of extraversion.

Next, we tested whether participants who displayed a more

intense smile in their Facebook photo were also more

satisfied with their first-semester social relationships. As in

Study 1, this was indeed the case (see Table 2). Additionally,

first-semester satisfaction with social relationships predicted

life satisfaction in the final semester of college. Both smile

intensity and social relationships satisfaction, then, were

unique predictors of future well-being. We conducted a media-

tion analysis, again using Mplus 4.21’s (Muthén & Muthén,

2007) bias corrected bootstrap method. In a more decisive

showing than the results of Study 1, satisfaction with social

relationships mediated the longitudinal association between

smile intensity and life satisfaction, indirect effect ¼ .13 (95% CI ¼ [.03, .28]), z ¼ 2.51, p < .05.

In sum, we were able to replicate each of the main find-

ings from Study 1 in our second cohort of male and female

students—who entered college a year later (in fall 2006)

when Facebook usage had more than doubled. In addition,

we addressed the lack of (expected) correlation between

extraversion and smile intensity in the first study using a

different measure of extraversion. Although extraversion

scores were correlated with smile intensity in the current

study, smile intensity again remained a unique predictor

of future life satisfaction controlling for extraversion.

Table 2. Descriptive Statistics and Correlations Among Key Variables in Study 2

Smile LS1 LS2 Extra Social Relationships

Satisfaction M (SD) a

Smile intensity — .38* .57** .39* .44** 7.22 (2.50) .96 Life satisfaction 1 — .72** .37*** .78** 25.60 (5.85) .92 Life satisfaction 2 — .59** .76** 26.55 (5.95) .91 Extraversion — .69** 4.22 (1.29) — Social relationships satisfaction — 5.61 (0.88) .55

***p < .10. *p < .05. **p < .01. Smile intensity, life satisfaction 1 (LS1), extraversion, and social relationships satisfaction were measured in the first semester of college. Life satisfaction 2 (LS2) was assessed 3.5 years later (in the final semester of college). Extraversion (a single-item) could range from 1 to 6.

410 Social Psychological and Personality Science 3(4)

Building on the results of Study 1, in this cohort we also

found that first-semester satisfaction with social relation-

ships mediated the longitudinal association between smile

intensity and life satisfaction.

Combined Mediation Analysis

Because the sample size in our two studies was relatively small

for mediation analysis, it could have produced a biased esti-

mate (Fritz & MacKinnon, 2007). Therefore, we repeated the

mediation analysis, this time with the combined data from

Studies 1 and 2 (n ¼ 84). As seen in Figure 1, smile intensity in the first-semester Facebook profile photo predicted the qual-

ity of social relationships, which in turn predicted life satisfac-

tion at the end of college, indirect effect ¼ .08 (95% CI ¼ [.02, .16]), z ¼ 2.32, p < .05. Thus, we can conclude with greater cer- tainty that the longitudinal association between smile intensity

and life satisfaction was partially mediated by the quality of

participants’ first-semester social relationships.

General Discussion

We began by testing the possibility that the intensity with

which college students were smiling in their first-semester

Facebook profile photos would predict future self-reported life

satisfaction—just as formal photos did in past research. In two

longitudinal studies (the first of which consisted of early adop-

ters of Facebook), we found that female and male participants

who displayed a more intense smile in their first-semester pro-

file photo were indeed more satisfied with their lives during

that first semester at college—and, more importantly, 3.5 years

later as they were about to graduate from college. In addition,

the latter finding held even when we controlled for first-

semester life satisfaction. Thus, we were able to replicate (for

the first time) the work of Harker and Keltner (2001) in two

coed samples, and extend it in another key way by showing that

smile intensity also predicted changes in self-reported well-

being over time.

We next set out to take steps toward clarifying why smile

intensity might predict future self-reported well-being. First,

we examined the possibility that the longitudinal association

between smile intensity and life satisfaction would be

explained by extraversion. This seemed plausible in that extra-

version is typically correlated with well-being. Using two dif-

ferent measures of extraversion, however, we found no

evidence for this third variable account.

Because relationships are positively associated with long-

term well-being, we also sought to determine whether the link

between smile intensity and future life satisfaction might be

explained by the quality of participants’ social relationships.

In our two studies, participants who displayed a more intense

smile in their first-semester Facebook profile photos were

indeed more satisfied with their social relationships during that

time period. Defying simple explanation, however, smile inten-

sity and social relationships satisfaction were both shown to be

unique predictors of life satisfaction at the end of college. By

using the combined data from our two studies in order to max-

imize statistical power, we found that the link between smile

intensity and future life satisfaction was partially mediated

by first-semester social relationships satisfaction. This provides

us with the first-ever evidence of a complex causal link

between these variables. Because the mediation was partial and

our design was limited, however, we are left with far more

questions than answers about the meaning of these particular

results. Future research is thus required in order to determine

the specific social/relationship processes at play. But which

processes seem most worthy of consideration?

First, it is plausible that an intense smile displayed in a Face-

book profile photo (especially in a college context) indicates

that people will be likely to act similarly in ‘‘real life.’’ If so,

those who tend to display more positive affect may seem more

friendship-worthy and approachable. This type of ‘‘smile-as-

approach-signal’’ strategy could prove to be especially benefi-

cial when people are new to a social environment (e.g., in the

first semester of college). Some past research has shown, for

example, that smiling individuals are perceived by strangers

to be more extraverted, agreeable, conscientious, open, and

emotionally stable (Naumann et al., 2009; Table 3).

Second, those who display more positive affect during inter-

actions may be likely to elicit similar responses in others. To

the extent that people value those who give them reason to

smile, individuals who tend to smile intensely may be more

sought-after as interaction partners. Just as positive emotions

build good relationships (Waugh & Fredrickson, 2006), then,

a more intense display of positive affect in the context of social

interactions may play an active role in helping to solidify peo-

ple’s relationships over time and give rise to higher levels of

life satisfaction.

Before drawing any conclusions, however, it is important to

recognize several limitations of the current research. First, as

noted, our design prevented us from being able to identify why

relationship quality partially mediated the link between smile

First Semester Smile

Life Satisfaction at the End of College

Social Relationship Satisfaction

.33** .32**

.40**

First Semester Smile

Life Satisfaction at the End of College

.51**

Figure 1. The direct longitudinal association between smile intensity in the first-semester Facebook profile photo and life satisfaction at the end of college, and the mediation analysis of the combined Studies 1 and 2 data. Note. Numbers indicate standardized regression coefficients.

Seder and Oishi 411

intensity and later life satisfaction. The two processes detailed

above need to be tested in the future. Second, a robust relation-

ship between people’s affective displays in photographs and

their real-world display behaviors has been predicted (e.g.,

Keltner, 2004) but has yet to be proven. More research is thus

needed on this important (and likely complex) variable. Third,

although we found no evidence for the extraversion-as-third-

variable account, we did so via use of two brief measures of

extraversion. Use of extended self-report measures will be ben-

eficial in future research, as a specific facet of extraversion

could prove to be a key third variable underlying the associa-

tion between smile intensity and future life satisfaction. Fourth,

because of the temporal sequence of our measurement (i.e.,

photos were posted to Facebook before the Time 2 self-report

measures were completed), we did not test the reverse media-

tion model (social relationships ! smile intensity ! future life satisfaction). Conceptually speaking, however, it is possible

that having good social relationships gives people more reason

to smile intensely—on Facebook and in real life—which in

turn gives rise to higher levels of life satisfaction over time.

Clearly, it is important to test various alternative models of

smile intensity and well-being in the future.

Taken as a whole, the current research represents a sizable

(and long overdue) step forward in the quest to understand

whether and why affective displays in publicly shared photo-

graphs can predict future well-being. Because this program

of research is still relatively ‘‘young,’’ numerous other impor-

tant questions seem warranted. Will our findings extend to

other college students in the United States? More importantly,

will they extend to older (or younger) Americans—and to cul-

tural contexts in which a smile is not always prized (e.g.,

China)? Might different types of smiles (Niedenthal, Merillod,

Maringer, & Hess, 2010) and variability in smile intensity

across different contexts (e.g., informal vs. formal photos and

solo vs. social photos) relate to well-being differently?

Additionally, some recent research has shown that observers

can, with surprising accuracy, judge the extent to which people

are extraverted or agreeable (Vazire & Gosling, 2004) or nar-

cissistic (Buffardi & Campbell, 2008) just by viewing the con-

tent of their online profiles (e.g., on Facebook). Do such

findings suggest that untrained observers might also be able

to infer people’s (current or future) well-being or social rela-

tionships satisfaction just by looking at the extent to which they

are smiling in a photo (or photos)? Given that many people con-

sult social networking websites in order to ‘‘screen’’ (for worse

or for better) prospective friends, dates, and colleagues, the lat-

ter question is certainly worthy of investigation.

In times prior to the advent of the Internet in the late 1990s,

most college students had at least one thing in common with the

women in Harker and Keltner’s (2001) study: A single, formal

graduation yearbook photo was likely to be the only public

photographic record of their time in college. The participants

in our two studies, however, were members of the first two

national cohorts of college students who were able and willing

to document the entirety of their college years (and beyond) via

photos and other content posted to the social networking

website Facebook. Hundreds of millions of people around the

world (of all ages) are now following that lead in their own

lives. In combination with the promising results of our two

studies, the latter development suggests that there has never

been a better time than the present for researchers to learn what

subtle affective displays—such as the intensity with which peo-

ple are smiling in photos posted to Facebook—might reveal

about longitudinal well-being in different populations and

cultures.

Acknowledgments

The authors would like to thank Jonathan Haidt, James E. Burroughs,

Gerald Clore, and Amori Yee Mikami for their invaluable comments

on earlier versions of our article.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to

the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, author-

ship, and/or publication of this article.

Notes

1. Most participants (n ¼ 41) completed a measure of life satisfaction at Time 1 (the departmental pretest). We found no differences in

life satisfaction or extraversion (also measured at Time 1) when

we compared our participants with other first-year students in the

participant pool (n ¼ 353; fall 2005), |t|s < .751, ps > .453. Although our sample was of modest size, then, it appears that our

participants were not atypical members of their university cohort.

2. Facebook profile photos are typically of high-enough resolution to

display in a web browser at 600 � 600 (or larger) with little loss of image quality.

3. In line with past research, extraversion did correlate with Life

Satisfaction 1 (see Table 1).

4. Unfortunately, we failed to obtain a larger sample for Study 2. Dur-

ing this time period, an increasing number of Facebook users may

have become reluctant to share their profile information because of

privacy concerns.

5. As in Study 1, we found no differences in life satisfaction or extra-

version (both at Time 1) when we compared our participants (n ¼ 27) with other first-year students in the pool (n ¼ 344; fall 2006), |t|s < .732, ps > .465. We also found no differences related to num-

ber of Facebook friends or to estimated frequency of updating their

Facebook profile, |t|s < 1.08, ps > .280. As with Study 1, then, our

sample appeared to be typical members of their university cohort.

References

Abel, E. L., & Kruger, M. L. (2010). Smile intensity in photographs

predicts longevity. Psychological Science, 21, 542-544;

doi:10.1177/0956797610363775

Back, M. D., Stopfer, J. M., Vazire, S., Gaddis, S., Schmukle, S. C.,

Egloff, B., & Gosling, S. D. (2010). Facebook profiles reflect

actual personality not self-idealization. Psychological Science,

21, 372-374.

412 Social Psychological and Personality Science 3(4)

Brody, N., & Ehrlichman, H. (1997). Personality psychology: The sci-

ence of individuality. Upper Saddle River, NJ: Prentice Hall.

Buffardi, L. E., & Campbell, W. K. (2008). Narcissism and social net-

working web sites. Personality and Social Psychology Bulletin, 34,

1303-1314.

Diener, E., Emmons, R. A., Larsen, R. J., & Griffin, S. (1985). The satis-

faction with life scale. Journal of Personality Assessment, 49, 71-75.

Diener, E., Oishi, S., & Lucas, R. E. (2003). Personality, culture, and

subjective well-being: Emotional and cognitive evaluations of life.

Annual Review of Psychology, 54, 403-425.

Diener, E., & Seligman, M. E. P. (2002). Very happy people. Psycho-

logical Science, 13, 81-84.

Facebook.com Press Room Statistics. (2010). Retrieved from http://

www.facebook.com/press/info.php?timeline

Freese, J., Meland, S., & Irwin, W. (2007). Expressions of positive

emotion in photographs, personality, and later-life marital and

health outcomes. Journal of Research in Personality, 41, 488-497.

Fritz, M. S., & MacKinnon, D. P. (2007). Required sample size to

detect the mediated effect. Psychological Science, 18, 233-239.

Gosling, S. D., Rentfrow, P. J., & Swann, W. B. (2003). A very brief

measure of the Big Five personality domains. Journal of Research

in Personality, 37, 504-528.

Harker, L., & Keltner, D. (2001). Expressions of positive emotions in

women’s college yearbook pictures and their relationship to life

outcomes across adulthood. Journal of Personality and Social Psy-

chology, 80, 112-124.

Hertenstein, M. J., Hansel, C. A., Butts, A. M., & Hile, S. N. (2009).

Smile intensity in photographs predicts divorce later in life. Moti-

vation and Emotion, 33, 99-105.

Keltner, D. (2004). Ekman, emotional expression, and the art of

empirical epiphany. Journal of Research in Personality, 38, 37-44.

LaFrance, M., Hecht, M. A., & Paluck, E. L. (2003). The contingent

smile: A meta-analysis of sex differences in smiling. Psychological

Bulletin, 129, 305-334.

Muthén, L. K., & Muthén, B. O. (2007). Mplus user’s guide. (4th ed.).

Los Angeles, CA: Muthén & Muthén.

Naumann, L. P., Vazire, S., Rentfrow, P. J., & Gosling, S. D. (2009).

Personality judgments based on physical appearance. Personality

and Social Psychology Bulletin, 35, 1661-1671.

Niedenthal, P. M., Mermillod, M., Maringer, M., & Hess, U. (2010).

The simulation of smiles (SIMS) model: Embodied simulation and

the meaning of facial expression. Behavioral and Brain Sciences,

33, 417-480.

Preacher, K. J., & Hayes, A. F. (2008). Asymptotic and resampling

strategies for assessing and comparing indirect effects in multiple

mediator models. Behavior Research Methods, 40, 879-891.

Vazire, S., & Gosling, S. D. (2004). e-Perceptions: Personality impres-

sions based on personal websites. Journal of Personality and

Social Psychology, 87, 123-132.

Waugh, C. E., & Fredrickson, B. L. (2006). Nice to know you: Positive

emotions, self-other overlap, and complex understanding in the

formation of new relationships. Journal of Positive Psychology,

1, 93-106.

Bios

J. Patrick Seder, PhD, is a postdoctoral researcher at University of

Virginia. His research focuses on well-being, positive emotions, cul-

ture, and social processes.

Shigehiro Oishi, PhD, is an associate professor at University of

Virginia.

Seder and Oishi 413