
Violent video game effects on aggression, empathy, ... a meta-analytic review - ColinWright
http://www.ncbi.nlm.nih.gov/pubmed/20192553
======
jonnathanson
Here's an interesting tidbit:

 _"Moderator analyses revealed significant research design effects..."_

What that means is that the design and sample selection of the studies
influenced the outcomes of the studies to a large degree. Oftentimes, we see
this happen in studies that draw from clusters of the population. Clusters are
not truly random samplings. So when you take a sample population from a
cluster -- be it geographic, ethnic, national, political, etc. -- you're run
the risk of not taking a genuinely population-representative sample. Your
sample population is likely to be more homogenous than a truly random sampling
would be, as seen in a lower variance rate among respondents than you'd expect
to find from a random sampling.

This is all well and good if what you're testing is the effect of X or Y _on
that cluster_. But if you're trying to study effects of X or Y on the _general
population_ , then cluster sampling is far from ideal.

Let's say I'm designing a study called "National Attitudes Toward Ohio State
Football." And for my sample population, I select 500 study participants from
the state of Michigan. Would anyone in his right mind believe that my study
will produce a nationally representative outcome? Similarly, if I'm doing a
study called "The Effect of Gas Prices on Grocery Budgets," I might be pre-
biasing my outcome if I select from a cluster of long-commute suburbanites. Or
from a cluster of poor people. Or a cluster of rich people. Etc.

It's hard to know what sort of design effects were noticed in the various
studies aggregated into this particular meta analysis, or how the meta-
analysis attempted to compensate for such effects. But the presence of that
line in the abstract gives cause for concern.

~~~
pygy_
They obviously took the effect into account, at least to some extent.

What do you find worrying? That they may not have dealt with it thoroughly
enough?

Edit:

Actually, they mean that they took different study design (short-term,
experimental vs long term, observational, etc...) into account.

~~~
tedunangst
I think he's worried they didn't reach the conclusion he wanted.

~~~
niels_olson
this. As usual, the dominant trend on HN takes the line that pediatricians,
psychiatrists, etc, make weak claims about violent video games, backed up by
weak evidence. In reality, its a tough public health study to do, but the
effects are quite noticeable in clinic. The docs stand to gain nothing on this
except maybe some additional adderall or anti-depressants, scrips, which most
of us aren't very fond of writing. Maybe, just maybe, some of us might look
out for the public interest.

And maybe, just maybe, some computer gamers and game authors have demonstrated
a pattern of turning a blind eye to evidence that doesn't satisfy their
position.

------
edtechdev
This linked response discusses several problems with this meta-analysis, and
the fact that most other meta-analyses have found no effect:
<http://www.ncbi.nlm.nih.gov/pubmed/20192554>

"Several recent meta-analyses, examining outcome measures most closely related
to serious aggressive acts, found little evidence for a relationship between
violent video games and aggression or violence. In a new meta-analysis, C. A.
Anderson et al. (2010) questioned these findings. However, their analysis has
several methodological issues that limit the interpretability of their
results. In their analysis, C. A. Anderson et al. included many studies that
do not relate well to serious aggression, an apparently biased sample of
unpublished studies, and a "best practices" analysis that appears unreliable
and does not consider the impact of unstandardized aggression measures on the
inflation of effect size estimates. They also focused on bivariate
correlations rather than better controlled estimates of effects. Despite a
number of methodological flaws that all appear likely to inflate effect size
estimates, the final estimate of r = .15 is still indicative of only weak
effects."

Meta-analyses are usually either a cheap way to get a well-cited publication
or a way to impose one's biases on other people's research. They're rarely as
useful as some people would like to think, and the issue a meta-analysis
reviews is rarely as simple as some would like to think.

That said, I've got an almost 8 year old, and I obviously don't let him play
videos games or watch TV shows with explicit violence (blood, gore, realistic
violence, etc.). So for example Mario Kart is okay, but Family Guy is not
(they often show bloody violence).

------
Anechoic
(I'm not trying to troll the thread, I'm not trying to stir up any trouble, I
am asking a sincere question, so please be gentle)

Why is it that whenever someone makes a link between violent video games and
violent real life behavior the studies are widely considered to be unfounded,
yet folks seem to believe that many of the ills that affect black communities
can be directly attributable to aspects of "black culture" (gangsta rap and
minstrel media in particular)? There are certainly studies that make the case
for the link in both instances, but the conventional wisdom for the two seem
to be stark opposites. I've seen these differing beliefs expressed in
discussions at Reddit, Ars Technica, and to a lesser extent here.

Why is it that video games can't possibly be a problem, but gangsta rap is
most certainly the problem?

(Again, not trying to be a troll, I'm just wondering if there is some
fundamental difference that perhaps I've missed. This is your chance to
enlighten me.)

~~~
lukifer
I'm interested in a similar question: how come no one asks about the
psychosocial influence in glorifying the military, whether in the context of
movies, games, or history classes? I understand that there are circumstances
where military action is a necessary evil, but it's always seemed to me that
there are some people who get a little too excited by socially sanctioned
violence.

------
greendestiny
I've read this study before and I couldn't analyse it in the detail it
probably warrants - but I couldn't help but think that this meta study
deliberately ignores that teenage boys going through puberty may correlate
with these changes. If you don't consider something that's been understood for
thousands of years its probably disingenuous.

~~~
pygy_
I can't read the article either, but you make a lot of assumptions here. One
of them supposes that the authors are idiots, and another one is simply wrong.

Whatever the design, studies without proper control groups are useless. People
who do and review meta-analysis are very aware of methodological pitfalls, and
the likelihood of seeing a meta-analysis based on such papers is extremely
small.

The abstract also mentions that there is no gender effect, barring the "boys"
part of your "teenage boys" argument.

~~~
greendestiny
No I mean I have read the article, I just didn't go that into depth. And it
very explicitly points out that there is a gender effect. The author has made
a career being the academic against violent games - you don't need to be an
idiot to have an agenda.

~~~
pygy_
Edit: a link to the full text is posted in this comment:
<http://news.ycombinator.com/item?id=2880901>

\-- The paper reports no significant sex effect: --

 _There was no evidence that the VGV effect on aggressive behavior differed
for males and females (ps  .10). The VGV effect was slightly larger for
females in experimental and longitudinal studies and was slightly larger for
males in the crosssectional studies, but none of these differences were
significant._

\-- The age effect is only borderline significant: --

 _Average age of the participants was not significantly related to the VGV
effect sizes in experimental or longitudinal studies ( ps  .50). However, it
is important to note that there were no longitudinal studies on participants
older than 16. For crosssectional studies there was a marginally significant
effect of age (b  .005, Z  1.82, p  .07). Studies with older participants
tended to yield slightly smaller effect sizes than did those with younger
participants_

\--

Anyone with a dash of understanding of the human mind wouldn't find these
results surprising, BTW. Even if you're able to make the difference between
real life and games, acting violently in virtual environments trains your
brain to react more violently in general.

BTW, I don't have any personal bias against violent video games.

\-- Initial post, before the editions:

Indeed, then, and I'm a bit surprised that the peer review accepted an
abstract that contradicts the content of the paper. Is the journal also biased
against violent games?

~~~
greendestiny
I think peer review is a very basic hurdle in the research process. The
results are then up for review - and that's what we're doing here in a minor
way. In the section that really matters, violent behaviour, results seem
massively skewed in favour of results from cross-sectional studies.
Experimental and longitudinal studies showed strong sex differences. All non-
experimental (and no doubt some of the experimental) studies were strongly
subject to self-selection. None of the longitudinal studies were done on
subjects over 16. Just because its a meta-study doesn't mean it isn't subject
to massive flaws.

Does anything in there reliably address the issue of correlation versus
causation. Most people play video games - if I was a violent person surely
that would be my entertainment of choice right?

------
onli
Have a look at this FAQ from one of the authors from 2009:
[http://www.psychology.iastate.edu/faculty/caa/Video_Game_FAQ...](http://www.psychology.iastate.edu/faculty/caa/Video_Game_FAQs.html)

Totally surprising that a following meta(!)-study has the same conclusion.

It is known for years that studies in that area are biased
(conservative/christian sponsors?) and are often eager to see casualty where
none can be proven. A meta-study proves only that such studies exist.

~~~
zokiboy
Meta study had to be completed before 2010 to be published in Mar 2010. FAQ
was published in 2009, I guess at the same time the paper was submitted for
review. That's the reason for having same conclusions.

~~~
onli
The FAQ mentions an article from 2003. I don't know these people, don't know
if this role is part of their academic career like suggested in a comment
above, but even being of that opinion such a long time suggests a bias when
starting a new study.

------
zokiboy
Full text:
[http://www.psychology.iastate.edu/faculty/caa/abstracts/2010...](http://www.psychology.iastate.edu/faculty/caa/abstracts/2010-2014/10asisbsrs.pdf)

