It Is Developmental Me, Not Generation Me: Developmental Changes Are More Important Than Generational Changes in Narcissism-Commentary on.

Abstract

In this article, we make two points about the ongoing debate concerning the purported increase in narcissistic tendencies in college students over the last 30 years. First, we show that when new data on narcissism are folded into preexisting meta-analytic data, there is no increase in narcissism in college students over the last few decades. Second, we show, in contrast, that age changes in narcissism are both replicable and comparatively large in comparison to generational changes in narcissism. This leads to the conclusion that every generation is Generation Me, as every generation of younger people are more narcissistic than their elders.

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Perspectives on Psychological
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DOI: 10.1177/1745691609357019
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Brent W. Roberts, Grant Edmonds and Emily Grijalva
Generational Changes in Narcissism - Commentary on Trzesniewski & Donnellan (2010)
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It Is Developmental Me, Not Generation
Me: Developmental Changes Are More
Important Than Generational Changes in
Narcissism—Commentary on Trzesniewski
& Donnellan (2010)
Brent W. Roberts
1
, Grant Edmonds
1
, and Emily Grijalva
1
1
University of Illinois, Urbana-Champaign, Champaign, IL
Abstract
In this article, we make two points about the ongoing debate concerning the purported increase in narcissistic tendencies in
college students over the last 30 years. First, we show that when new data on narcissism are folded into preexisting meta-
analytic data, there is no increase in narcissism in college students over the last few decades. Second, we show, in contrast, that
age changes in narcissism are both replicable and comparatively large in comparison to generational changes in narcissism. This
leads to the conclusion that every generation is Generation Me, as every generation of younger people are more narcissistic than
their elders.
Keywords
narcissism, personality development, cohort, Generation Me, meta-analysis
I see no hope for the future of our people if they are dependent
on the frivolous youth of today, for certainly all youth are
reckless beyond words. When I was a boy, we were taught to
be discrete and respectful of elders, but the present youth are
exceedingly wise and impatient of restraint
—Hesoid, 700 BC
Arguments for and against the generation-to-generation
increase in narcissism have lately spilled out over a number
of articles across a variety of different journals. In the initial
salvo, year-to-year scores on the Narcissistic Personality
Inventory (NPI; Raskin & Terry, 1988) were compiled to esti-
mate whether college undergraduates were growing more nar-
cissistic with each passing decade since the early 1980s
(Twenge, Konrath, Foster, Campbell, & Bushman, 2008). This
meta-analytic review pointed to an increase in narcissism of
approximately one third of a standard deviation from the early
1980s to 2006. The apparent increase in narcissism, coupled
with other indicators of increasing self-focus, formed the basis
of the attribution that Americans born after 1970 should be
described as ‘‘Generation Me’’ (Twenge, 2006). This pub-
lication was followed with one describing new data on the NPI
showing little or no change in very large samples from 1996 to
2006 (Trzesniewski, Donnellan, & Robins, 2008) and the
subsequent arguments over these new data (Donnellan,
Trzesniewski, & Robins, 2009; Twenge & Foster, 2008).
We have followed the arguments over the secular trends in nar-
cissism with great curiosity. Generational changes in personality
are intrinsically interesting because they have the potential to
demonstrate the effect of culture on personality development
(Schaie, 1965). In fact, generational or cohort differences are an
important element of developmental science. Our interest in secu-
lar changes in narcissism was especially high, as we had shown
similar effects of increasing narcissistic qualities in generations
coming of age in the 1960s and 1970s (Roberts & Helson, 1997).
As the exchange has proceeded, we felt that two simple
points have not been emphasized enough. First, the discourse
started with the publication of a meta-analysis and has since
migrated to arguments over new data (Donnellan et al., 2009,
Twenge & Foster, 2008). Although meta-analyses are far from
Corresponding Author:
Brent W. Roberts, Department of Psychology, University of Illinois, Urbana-
Champaign, 603 East Daniel Street, Champaign, IL, 61820.
E-mail: broberts@cyrus.psych.uiuc.edu
Perspectives on Psychological Science
5(1) 97–102
ªThe Author(s) 2010
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perfect, we believe that if used responsibly, they can lead to
stronger, more defensible conclusions (Roberts, Walton, &
Viechtbauer, 2006). Meta-analyses are intrinsically more effi-
cient because they use more information. Rather than arguing
over the features of new data, an overlooked alternative is to
simply fold new data reported in papers such as Donnellan
et al. (2009) into the old meta-analysis and see what comes
of it. We do this later in this article.
Second, generational or cohort differences in personality
address a developmental question: How does growing up in a
different context affect the personalities of people experiencing
that context? The assumption behind cohort differences is that
pervasive cultural values and practices change over time. If the
arguments behind Generation Me (Twenge, 2006) are correct,
these changes in cultural values mean that the youth of today
are brought up in a more permissive and self-serving culture.
Experiencing a culture that serves the needs of the individual
over society is presumed to lead young people of recent history
to be more narcissistic than the young people of previous
generations.
For our second point, we would like to highlight an issue
seemingly forgotten in this debate, which is that personality
development is broader in scope than the study of cultural
changes and their potential effect on development. Develop-
ment includes the patterns of continuity and change in person-
ality over the life course and the potential factors that might
influence those patterns. Changes in culture are but one of
many potential factors that may influence levels and changes
in narcissism. Moreover, if we are to understand and appreciate
the meaning of changes in narcissism from generation to gen-
eration, the most relevant comparison context is a developmental
one—how much does narcissism change across the life course,
for example? To this end, we compare generational shifts in
narcissism with age-graded role differences in narcissism.
Meta-Analysis: Having Faith in the Data
Having done a few meta-analyses, we are predisposed to prefer
the technique for a variety of reasons. Certain features of a
meta-analytic approach are just good science. Replication is
intrinsic to the meta-analytic process as one cannot do a
meta-analysis unless the same question has been addressed
across multiple studies. Replication is the bedrock of science.
If findings fail to replicate across time and different labs, then
it is appropriate to discount the original results. Also, given the
right circumstances a meta-analysis can provide a more objec-
tive perspective on research findings as it is inclusive of data
from different labs. In the absence of a meta-analysis, there
is a propensity to prioritize one’s own data over those of other
researchers (Luborsky et al., 1999). A meta-analysis is a cruel
arbiter of conflict across labs as it aggregates findings among
researchers who are often motivated by different reasons to
do the same research.
Finally, and most importantly, meta-analysis protects
researchers from ‘‘sampling error syndrome.’’ This is the pro-
pensity to believe one’s own data over others’ and put
disproportionate faith in the results of studies based on small
groups (Schmidt, 1992). It has been said that psychologists
do not sample from populations, rather psychologists study
small unrepresentative groups that have little or no generaliz-
ability (Cohen, 1990; Sears, 1986). The findings that derive
from these groups are often too particular to our samples, and
of course, we tend to believe these results more than they
deserve. By leveraging across many studies, a meta-analytic
approach can help to diminish the symptoms of sampling error
syndrome.
This is not to say that meta-analyses are without flaw or
beyond reproach. Meta-analyses, like many other approaches,
are subject to the garbage-in/garbage-out phenomena. They are
only as good as the data on which they are based. If one meta-
analyzes a set of small studies of particular groups, then the
meta-analysis may simply reify sampling error. Likewise, no
meta-analysis is so definitive so as to nullify the importance
of new data, which may provide distinctly new perspectives
on existing issues because of methodological or conceptual
improvements.
As noted above, new data on cohort differences in narcis-
sism, or the lack thereof, have been pored over in a series of
studies (Donnellan et al., 2009; Trzesniewski et al., 2008;
Twenge & Foster, 2008). These new data have spawned more
debates, but they have not been used in a way that makes sense
to us, such as adding them to the meta-analytic database rather
than arguing over their merits. We believe that a closer approx-
imation to the truth can be gained by folding the new data on
narcissism into the existing meta-analytic database rather than
arguing over the particular make-up of the samples contained
in these new data. Therefore, we reanalyze the meta-analytic
findings reported in Twenge et al. (2008) by using the data
as published and adding the new data presented by Donnellan
et al. (2009) and data that we collected recently in our lab.
First, we analyzed the original data reported in Twenge et al.
(2008) to replicate their findings. We reanalyzed the data mul-
tiple ways, including the techniques reported in the original
article and in the reanalysis reported in Donnellan et al.
(2008).
1
But to better show the effects in the original data and
the effects of adding new data, we adopted a simpler approach
to the analyses. Specifically, we aggregated data within year or
clusters of years depending on the amount of data available. If
there were only one or two samples for a given year, we simply
aggregated that year’s data with the next (i.e., aggregating the
1995 data with the 1996 data). We then weighted the means
within each grouping by the inverse of the variance (n/SD
squared) to determine a population estimate of the mean, var-
iance, effect size, and confidence interval for each period.
We also computed Q, the standard index of effect size hetero-
geneity, to test whether there was statistically significant varia-
bility within each period.
The results are shown in Figure 1 and Table 1. In Figure 1,
the dashed line depicts the reanalysis of the original meta-
analysis, which closely tracks the estimates provided by the
regression equation predicting narcissism scores from year of
assessment originally reported in Twenge et al. (2008). Mean
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narcissism scores show a clear increase across the 30-year
period from 1982 to 2006. Consistent with the findings
reported in the original article, the difference between the most
recent estimates and the estimates drawn from the mid 1980s
show an increase of approximately one third of a standard
deviation. So, using the original data published in Twenge
et al. (2008), it would be reasonable to conclude that narcissism
has been on the increase over the last three decades, even when
one uses a conservative approach with the data from the orig-
inal meta-analysis.
The solid line on Figure 1 shows the effects of folding in
data reported in Donnellan et al. (2009) and data from our
recent survey of University of Illinois students (more details
on this sample are given below). The results reported in
Donnellan et al. (2009) were interesting for two reasons. First,
they tracked NPI scores from 1996 to 2008, so multiple sam-
ples could be folded into the original data set reported by
Twenge et al. (2008) across the last decade. Second, the
samples were rather large (e.g., over 4,000) in comparison to
the samples compiled in the original data set. One key feature
of meta-analytic estimates is that they weight large samples
more heavily than small samples under the assumption that
large samples provide a better approximation to the true popu-
lation mean. The data from our most recent study are interest-
ing because the overall mean score is only 15.7 (SD ¼6.6),
which is distinctly lower than many of the recent mean scores
for the NPI reported in Twenge et al. (2008).
As can be seen by the plot of the revised means in Figure 1,
incorporating these new data into the old meta-analysis had a
profound effect on the estimates of narcissism scores across the
last 30 years. In contrast to the steady increase shown in the
original study, the new estimates show little or no trend over
time. With the inclusion of more data, the evidence for Gener-
ation Me disappears. The ephemeral quality to the secular
trends in NPI scores would appear to indicate that the apparent
increase in narcissism is not very robust.
We believe that folding new data into the existing meta-
analysis is a more compelling test of whether there are genera-
tional shifts in narcissism than quibbling over the features of
new data. It is also a fair test of the original empirical article
(Twenge et al., 2008), as this approach is perfectly consistent
with the original approach: gather as much data as possible,
regardless of the ethnic or gender composition of the partici-
pants, and compile the data. When this is done, there are no
cohort effects on the NPI. Of course, this conclusion could
be modified with more data. Nonetheless, it serves to make the
point that the original meta-analytic approach is an excellent,
and preferred, way of testing the idea that NPI scores change
across generations.
Every Generation is Generation Me
Narcissism has been investigated with growing interest in per-
sonality, social, and clinical psychology. Much research has
Table 1. Meta-Analytic Estimates of NPI Scores From 1982 to 2006
Year Twenge effect size Updated effect size k(total ¼94) CI n (total ¼46,782)
1982–1990 15.44 15.44 5 15.15–15.74 1,975
1992–1993 15.56 15.56 5 15.19–15.94 1,268
1994–1995 16.77 16.77 5 16.29–17.25 746
1996 16.50 15.95 12 15.66–16.23 2,289
1997–1998 16.55 16.55 7 16.11–16.99 912
1999 16.86 16.86 11 16.54–17.19 1,607
2000 16.71 16.71 4 16.15–17.28 572
2001 16.27 16.27 9 15.90–16.64 1,363
2002 16.92 15.57 8 15.38–15.77 4,788
2003 15.74 15.25 5 15.07–15.44 5,488
2004 18.22 15.48 6 15.29–15.66 5,401
2005 17.26 15.97 7 15.80–16.14 6,562
2006 17.65 15.63 7 15.45–15.80 6,094
2007–2009 15.65 3 15.49–15.80 7,717
Note. The Twenge effect size was estimated using the data from Twenge, Konrath, Foster, Campbell, and Bushman (2008). The updated effect size was estimated
by adding the data from Donnellan, Trzesniewski, and Robins (2009) and the data on college students collected at the University of Illinois in 2009 (M¼15.69, SD
¼6.59, N¼234). k¼number of studies contributing to effect size estimate; CI ¼95% confidence level interval.
Fig. 1. College students Narcissistic Personality Inventory
(NPI) scores from 1982 to 2009. Yaxis represents one standard
deviation on the NPI scale. Dashed line shows results based on
data presented in Twenge et al. (2008). Solid line shows results
when new data is added to the original meta-analysis.
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focused on the measurement of narcissism (Emmons, 1987), its
interpersonal consequences (Paulhus, 1998), and its relation to
problematic behavior, like impulsivity (Vazire & Funder,
2006). Despite the renewed interest in narcissism very little
attention has been paid to the developmental antecedents
or patterns of change in narcissism over the life course (cf.
Carlson & Gjerde, in press).
How then does narcissism develop across the life course?
Conceptually and empirically, narcissism is a construct that
bridges pathological and normal functioning (Miller, Gaughan,
Pryor, Kamen, & Campbell, 2009). As a form of pathology,
narcissism reflects an unrealistic sense of entitlement and
grandiosity combined with a tendency to be hostile toward
others (Kernberg, 1975). Narcissism is a syndrome that is
distinctly difficult to overcome (Kernberg, 1975). Individuals
who think highly of themselves and are unimpressed with other
people have, by definition, a difficult time taking feedback. In
contrast, Kohut (1971) viewed narcissism both as a form of
pathology and as a normal stage of development. Conceptua-
lized as a normative issue of development, Kohut argued peo-
ple gradually move away from overt narcissism across the life
course. Children are, by nature, self-focused and narcissistic
according to adult standards of behavior. In the natural course
of development, the narcissistic self is slowly dismantled and
reintegrated into a healthy mature self that includes trans-
formed components derived from the early narcissistic self
(Kohut, 1971).
Seen from the lens of social investment theory (Roberts &
Wood, 2006; Roberts, Wood, & Smith, 2005), narcissism
should decrease with age because the normative paths people
follow entail making commitments to other people, such as
friends, family, and coworkers. Being hostile to the interests
of others, which is a key element of narcissism, would preclude
successful investment in the interpersonal roles of adulthood.
To the extent that making commitments to others is normative
across the life span, one would expect decreases in narcissism
as these commitments run contrary to the modal mind set of the
narcissist (Kernberg, 1986).
To our knowledge, there are only two studies that have
tracked narcissism across age groups using either longitudinal
or cross-sectional designs. Just recently, the first longitudinal
study of the development of narcissism was reported (Carlson
& Gjerde, in press). Consistent with expectations, narcissistic
adults were found to be more impulsive, histrionic, active, and
self-focused as children. Mean levels of observer-rated narcis-
sism actually increased in adolescence before reaching a pla-
teau in the transition from adolescence to young adulthood.
In contrast, a large, Internet-based study of a wide range of age
groups showed a robust decrease in narcissism across the life
course (Foster, Twenge, & Campbell, 2003). In fact, the mag-
nitude of change from adolescence to old age was approxi-
mately 1 entire standard deviation.
Like the putative secular trends in narcissism, robust age
differences would be more convincing if they replicated across
samples. Ironically, it is also important to replicate effects
across different cohorts to rule out the potential confounding
effect of secular trends in narcissism. To this end, we report
data taken from a recent study conducted on the topic of family
resemblance in our introductory personality course. The study
was designed to test the average correlation between children
and their relatives, including parents and grandparents. As part
of the assessment battery, we included the NPI (Raskin &
Terry, 1988). Inadvertently, we performed a direct replication
of Foster et al. (2003), with a cohort born approximately a
decade later. More interestingly, we could also categorize indi-
viduals by their age-graded role (e.g., student, parent, grandpar-
ent), in addition to age, to see if age or role were more strongly
related to NPI scores.
Figure 2 shows the mean scores for the age-graded roles of
student, parent, and grandparent. The age trend in NPI scores
in our sample replicated the mean scores reported in Foster
et al. (2003) almost perfectly.
2
More interestingly, when stra-
tified by the age-graded role, the magnitude of the decrease
across age was even more pronounced. The mean difference
between the typical college student and their grandparents
was greater than 1 standard deviation, which constitutes one
of the largest effect sizes found in psychological science
(Cohen, 1992). Clearly, Generation Me is a developmental,
not a generational, phenomenon. Every generation of young
people is substantially more narcissistic than their elders, not
because of cultural changes, but because of age-related devel-
opmental trends.
The age differences in narcissism hold profound implica-
tions for interpreting the purported cohort changes in narcis-
sism. If people decrease an entire standard deviation as they
age, then it is not surprising that many middle-aged and older
individuals would find younger people to be narcissistic. Com-
paratively speaking, they are. Furthermore, the age differences
in narcissism may be easily confused with generational
changes in narcissism. The distinction between younger people
being more narcissistic than older people and younger people
being more narcissistic than previous generations is probably
too subtle to detect (Ozer, 1993). In turn, when older people are
told that younger people are getting increasingly narcissistic,
Fig. 2. Age-graded role differences in narcissism. Yaxis
represents 1.5 standard deviations on the NPI. Error bars are
95% confidence intervals. Sample sizes for the groups were as
follows: students, N¼234; parents, N¼226; grandparents,
N¼16.
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they may be prone to agree because they confuse the claim for
generational change with the fact that younger people are
simply more narcissistic than they are. The confusion leads
to an increased likelihood that older individuals will agree
with the Generation Me argument despite its lack of empirical
support.
Conclusion
In this comment on Trzesniewski & Donnellan’s (2010) article
in this issue, we sought to make two points. Our reanalysis of
the original meta-analysis served the point of showing that
more data is actually better than less data. By simply adding
new data to that reported in the original meta-analysis we find
that the apparent effect of changing cultural values on narcis-
sism disappears. One could quibble about the composition of
the samples integrated into the meta-analysis, but doing so
would simultaneously call into question the original meta-
analysis as the composition of the samples in the original study
was not broken down by ethnicity or sex. Using the same
approach as the original study, we find that the core evidence
for the Generation Me effect is missing. Younger cohorts are
apparently not suffering from an increasing epidemic of
narcissism.
We would, however, like to comment about the potential
effect of sample composition on the changes, or lack thereof,
in narcissism over time. As a case in point, Table 2 shows the
NPI scores from our recent sample broken down by sex and
ethnicity within student and parent roles. None of the differ-
ences are large by effect size standards, yet there are several
striking consistencies across the student and parent groups and
between this sample and other studies that also report differ-
ences across demographic groups (e.g., Donnellan et al.,
2009). Specifically, men are more narcissistic than women
regardless of age. And African American groups score higher
on narcissism than other ethnic groups. In contrast to previous
research, the Asian groups in our study did not score conspicu-
ously lower on the NPI than did the remaining ethnic groups.
Two points can be inferred from these demographic differ-
ences in narcissism. First, the consistencies in demographic
differences in narcissism point to the fact that factors such as
sex and ethnicity are potential moderators of the differences
originally reported in Twenge et al. (2008) that should be
examined explicitly in future meta-analytic work on this topic.
If the sex and ethnic composition of samples varied over time,
then this might have influenced the reported means on the NPI
enough to make it look like there were generational changes in
narcissism. Second, the inconsistencies across our samples—
the Caucasians in our sample scored substantially lower than
did the Caucasians in most of the samples reported in Twenge
et al. (2008), whereas the Asians in our sample scored higher
than did those reported in Donnellan et al. (2009)—points to
the fact that sex and ethnic differences are often particular to
our specific samples. This only serves to emphasize our point
that a meta-analytic approach using more data is both more
conservative and potentially useful in determining the potential
effects of factors such as generation.
The second point we sought to make was that other aspects
of development were potentially more important than cohort or
generational changes. And, when it comes to the development
of narcissism, the effect of age and age-graded roles are far
more important than the effect of generation. This conclusion
would hold, even if the original findings of a small increase
in narcissism over the last few decades were true. This leads
to the obvious conclusion that finding young people to be nar-
cissistic is an aging phenomenon, not a historical phenomenon.
The fact that one can find complaints about the younger gener-
ation being more narcissistic going back to Hesiod helps make
the point that every generation is Generation Me. That is, until
they grow up.
Notes
1. We replicated the original findings from Twenge et al. (2008) by
using SPSS syntax to weight the data by sample size (B¼.53,
p< .001, k¼85). A more common approach to meta-analysis
would be to weight the results by the inverse of the sampling error
variance (Lipsey & Wilson, 2001).
2. The correlation between age and overall scores on the NPI was
.32 (p< .05, N¼591).
Declaration of Conflicting Interests
The authors declared no conflicts of interest with respect to the
authorship and/or publication of this article.
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