***** To join INSNA, visit http://www.insna.org ***** Well done, Elisa! An even funnier part of this article in Nature is a previous one they ran on the same topic about 10 years ago. The authors of that piece used the same linear extrapolation method and predicted by about this point in time that women would have surpassed men in world records for the marathon, with the other long distances soon to follow. Given the discrepancy with current reality, it's surprising that Nature continues to publish such foolhardy predictions based on unsound procedures. Take care, Devon On Thu, 3 Feb 2005, Bienenstock Elisa wrote: > ***** To join INSNA, visit http://www.insna.org ***** > > It is not only sociologists that find themselves perplexed by the review > process at Nature and Science. Last year there was an article in Nature > that will be useful to any of you tasked with teaching statistics, > because it is a beautiful example of how NOT to use Regression" > "Momentous sprint at the 2156 Olympics? Women sprinters are closing the > gap on men and may one day overtake them." NATURE|VOL 431 | 30 SEPTEMBER > 2004 |www.nature.com/nature. > > My husband, a muscle physiologists was outraged by the lack of any > intuition about physiology; I by the statistical violations, so we wrote > a reply: it was triaged. The paper extrapolated Olympic 100 meter times > for men and women to show that by the year 2156 woman will outpace men. > The linear model was not the best fit, but it was the "easiest and most > parsimonious." (We reevaluated the data using a spline which was the > best fit.) The researchers seemed to attribute the faster finishing > times to changes in physiology that occurred this century rather than > improvements in selection, nutrition, technology or training. > > The authors were not physicists. > > Below is the raw text of the reply (figures and citations not included). > If anyone is interested I can email you the PDF file. > > Gender gap revisited: a physiological glass ceiling? > Jon-Philippe K. Hyatt and Elisa Jayne Bienenstock > > The prospect that women will outpace men in future Olympic 100-meter > contests, as recently reported in Nature1, would indeed be a momentous > achievement in overcoming competitive, sociological, and physiological > barriers. Today, it is not uncommon for women to stand atop the podium > in ultra-endurance events: in 2002 and 2003, Pam Reed ran to victory > over all entrants in the 218-kilometre Badwater Ultramarathon (Death > Valley, USA), suggesting that the gender gap in competition is narrowing > rapidly2. There is no argument that 100-metre sprint times for men and > women also have converged; however, the predictions put forward by Tatem > et al.1 are untenable from a historical, statistical, and physiological > perspective. > > Assessment of gender-specific performance as a linear continuum (winning > time x year) assumes consistent historical variables. Since the early > 1980s, improvements in clothing, shoe technology, track surfaces, and > event-specific training have created advantages for today's Olympians. > Additionally, society's perception of women in sports advanced just > prior to this period as evidenced, for example, by the adoption of Title > IX in the United States in 1972. Assessing performance for each gender > must control for these recent technological and social advancements. > This is evident in our evaluation of the Olympic data: when women's > Olympic times (ref 1, see supplementary information) > are re-examined, curve- fitting models show that the year 1985 > delineates past and present Olympians (Fig. 1). Our new best- fit curve, > e.g. a spline, actually shows women's time increasing after 1985, which > is clearly an artifact resulting from the limited number of 100-metre > times from 1985-2004. > > Using one winning Olympic time per four years as the primary basis of > comparison limits our view of the potential held by each gender > especially since the Olympics do not necessarily represent the best > 100-metre times for men and women in the last 20 years. Expanding the > analysis using the 100-metre times from the World Championship final's > heat (www.iaaf.org/WCH03/history/index.html; for data set, see > supplementary information) from 1987-2003 shows that performance for men > and women have improved marginally, if at all (Fig. 1). Statistical > analyses reveal that, in fact, there is a poor relationship between 100- > metre times and year, supporting the notion that peak performance for > this event has reached a plateau for men and women. That sprint > performance and time (year) are unrelated in the past two decades > indicates that it is erroneous to predict future human success based on > past and present winning times3. > > The argument put forth by Tatem and colleagues is also physiologically > incorrect, as it ignores limitations that exist for the human body. For > instance, the logic of their linear continuum suggests that, given > enough time, men and women will outrun quadrupeds, automobiles, > airplanes, and even light, eventually crossing the finish line in less > then zero seconds. Will women ever out-sprint men in the 100-metre > event? Our examination of 100-metre times from recent years suggests > that we are reaching our physiological limits of performance2,4, > although there may be innovations through science and technology that > will allow us to embrace such a fantastic achievement when it happens. > > _____________________________________________________________________ > 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. > --------------------------------------------------------------------------- Devon D. Brewer Affiliate Assistant Professor of Anthropology, Psychology, and Sociology email: [log in to unmask] http://faculty.washington.edu/ddbrewer --------------------------------------------------------------------------- _____________________________________________________________________ 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.