***** To join INSNA, visit http://www.insna.org *****
Thanks. It is an interesting article indeed
(in fact it was available trough ArXiv since July 2010,
The issue revolved into an interesting debate. Partly covered here
I blogged about it too
Make sure you read contributions from both "sides", including
Fowler, James H. and Nicholas A. Christakis. 2008b. “Estimating peer
effects on health in social networks: A response to Cohen-Cole and
Fletcher and Trogdon, Nonnemaker, and Pais.” Journal of Health Eco-
and also a recent related paper by Noel & Nyhan
"The “Unfriending” Problem The Consequences of Homophily in Friendship
Retention for Causal Estimates of Social Influence"
On Wed, Jun 8, 2011 at 7:57 AM, Ilan Talmud <[log in to unmask]> wrote:
> ***** To join INSNA, visit http://www.insna.org *****
> Lyons, Russell (2011) "The Spread of Evidence-Poor Medicine via Flawed
> Social-Network Analysis," Statistics, Politics, and Policy: Vol. 2: Iss. 1,
> Article 2.
> DOI: 10.2202/2151-7509.1024
> Available at: http://www.bepress.com/spp/vol2/iss1/2Abstract
> The chronic widespread misuse of statistics is usually inadvertent, not
> intentional. We find cautionary examples in a series of recent papers by
> Christakis and Fowler that advance statistical arguments for the
> transmission via social networks of various personal characteristics,
> including obesity, smoking cessation, happiness, and loneliness. Those
> papers also assert that such influence extends to three degrees of
> separation in social networks. We shall show that these conclusions do not
> follow from Christakis and Fowler's statistical analyses. In fact, their
> studies even provide some evidence against the existence of such
> transmission. The errors that we expose arose, in part, because the
> assumptions behind the statistical procedures used were insufficiently
> examined, not only by the authors, but also by the reviewers. Our examples
> are instructive because the practitioners are highly reputed, their results
> have received enormous popular attention, and the journals that published
> their studies are among the most respected in the world. An educational
> bonus emerges from the difficulty we report in getting our critique
> published. We discuss the relevance of this episode to understanding
> statistical literacy and the role of scientific review, as well as to
> reforming statistics education
> ... summarizing the major problems with C&F’s studies:
> 1. The data are not available to others.
> 2. The unavailable data are sparse for friendships.
> 3. The models used to analyze the sparse data contradict the data and the
> 4. The method used to estimate the dubious models does not apply.
> 5. The statistical significance tests from the questionable estimates do not
> the proposed differences.
> 6. The wrongly proposed differences do not distinguish among homophily,
> and induction.
> 7. Associations at a distance are better explained by homophily than by
> Prof. Ilan Talmud, Ph.D.
> Head, Economic Sociology, Department of Sociology and Anthropology,
> University of Haifa
> Phones: 972-4-8240992 (office direct)
> 972-4-8240995 / 8249505 (secretaries)
> (cell) 972-522-220914 Fax: 972-4-8240819
> _____________________________________________________________________ SOCNET
> is a service of INSNA, the professional association for social network
> researchers (http://www.insna.org). To unsubscribe, send an email message to
> [log in to unmask] containing the line UNSUBSCRIBE SOCNET in the body of
> the message.
SOCNET is a service of INSNA, the professional association for social
network researchers (http://www.insna.org). To unsubscribe, send
an email message to [log in to unmask] containing the line
UNSUBSCRIBE SOCNET in the body of the message.