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==Data-mining birth month and disease==
[http://www.minnpost.com/second-opinion/2015/06/season-and-month-birth-linked-risk-disease-study-has-lots-caveats Season and month of birth linked to risk of disease, but study has lots of caveats]<br>
by Susan Perry, ''Minneapolis Post'', 11 June 2015
The article reports that
<blockquote>
The season — and even the specific month — in which we are born is associated with certain disease risks later in life,
according to a [https://en.wikipedia.org/wiki/Data_mining data-mining] [http://jamia.oxfordjournals.org/content/jaminfo/early/2015/06/01/jamia.ocv046.full.pdf study [PDF]] published this week in the [http://jamia.oxfordjournals.org/about Journal of the American Medical Informatics Association].
The study found, for example, that people born in early spring are at the highest risk of developing heart disease, while those born in early fall are most likely to develop respiratory illnesses.
Reproductive and neurological illnesses, on the other hand, were found to occur most often among people born during the early winter months.
As for individual birth months, the ones tied with the highest risk of disease were October and November, while May had the lowest risk.
</blockquote>
Perry cautions against over-interpreting the results, which show an association between birth-month and disease but do not prove a causal link.  Furthermore,
<blockquote>
...as [https://systemsbiology.columbia.edu/faculty/nicholas-tatonetti Nicholas Tatonetti], a co-author of the study and an assistant professor of biomedical informatics at Columbia University, noted in [http://newsroom.cumc.columbia.edu/blog/2015/06/08/data-scientists-find-connections-between-birth-month-and-health/ a released statement], “Even though we found significant associations, the overall disease risk is not that great. The risk related to birth month is relatively minor when compared to more influential variables like diet and exercise.”
</blockquote>
Later, we read,
<blockquote>
Here — with all of the caveats mentioned above — are some of those 16 medical conditions and the birth months associated with their highest and lowest risk:
* Atrial fibrillation (irregular heart beat): March (high), October (low)
* Essential hypertension (high blood pressure with no identifiable cause): January (high), October (low)
* Congestive heart failure: March (high) October (low)
* Acute upper respiratory infection: October (high), May (low)
* Prostate cancer: February (high), October (low)
* Overlapping cancer of the bronchus and lung: February (high), November (low)
* Bruising: December (high), April (low)
</blockquote> 
Perry's article contains a video of Tatonetti as well as an incomprehensible chart taken from Tatonetti.  The technical article's  Abstract says the results are based on data mining of
<blockquote>
1 749 400 individuals and found 55 diseases that were significantly dependent on birth month. Of these 19 were previously reported in the literature (p-value < .001) 20 were for conditions with close relationships to those reported and 16 were previously unreported. We found distinct incidence patterns across disease categories.
<br><br>
Conclusions: Lifetime disease risk is affected by birth month.  Seasonally dependent early development mechanisms may play a role in increasing lifetime risk of disease.
</blockquote>
Presumably readers of the journal are expected to respect the association/causation distinction--avoiding the slippery slope from "Lifetime disease risk is affected by birth month" to "Lifetime disease risk is caused by birth month."--and to interpret the P=values with appropriate caution.  Perry has certainly done a good job! 
Interestingly, the final summary section of the paper seems more carefully worded:
<blockquote>
We discovered 16 associations with birth month that have never been explicitly studied previously. Nine of these associations were related to cardiovascular conditions strengthening the link between cardiac conditions, early development, and Vitamin D. Seasonally-dependent early developmental mechanisms might play a role in increasing lifetime disease risk.
</blockquote>
Submitted by Paul Alper
==Bogus statistics==
==Bogus statistics==
[How To Spot a Bogus Statistic]<br>
[How To Spot a Bogus Statistic]<br>

Revision as of 20:37, 24 July 2015

Bogus statistics

[How To Spot a Bogus Statistic]
by Geoffrey James, Inc.com, 30 May 2015

The article begins by citing Bill Gates recent recommendation that everyone should read the Darrell Huff classic How to Lie With Statistics.

As an object lesson, James considers efforts to dispute the scientific consensus on anthropogenic climate change.


Submitted by Bill Peterson

Predicting GOP debate participants

Ethan Brown posted this following link on the Isolated Statisticians list:

The first G.O.P. debate: Who’s in, who’s out and the role of chance
by Kevin Quealy and Amanda Cox , "Upshot" blog New York Times, 21 July 2015

Sleeping beauties

Douglas Rogers sent a link to the following:

Defining and identifying Sleeping Beauties in science
by Qing Ke, et. al., PNAS (vol. 112 no. 24), 2015.

A "sleeping beauty" is an article one that achieves few if any citations in the years immediately following its publication, but then sees a large burst of interest many years later. The PNAS paper derives a so-called "beauty coefficient", denoted B, that depends on how many years the paper is dormant and how many citations it ultimately receives.

The PNAS paper is quite technical, but a popular account can be found here:

The sleeping beauties of science
by Nathan Collins, Pacific Standard, 28 May 2015

This article cites a 1901 paper by Karl Person, On lines and planes of closest fit to systems of points in space, as a classic sleeping beauty. It was not widely cited until 2002!

Some math doodles

<math>P \left({A_1 \cup A_2}\right) = P\left({A_1}\right) + P\left({A_2}\right) -P \left({A_1 \cap A_2}\right)</math>

<math>\hat{p}(H|H)</math>

Accidental insights

My collective understanding of Power Laws would fit beneath the shallow end of the long tail. Curiosity, however, easily fills the fat end. I long have been intrigued by the concept and the surprisingly common appearance of power laws in varied natural, social and organizational dynamics. But, am I just seeing a statistical novelty or is there meaning and utility in Power Law relationships? Here’s a case in point.

While carrying a pair of 10 lb. hand weights one, by chance, slipped from my grasp and fell onto a piece of ceramic tile I had left on the carpeted floor. The fractured tile was inconsequential, meant for the trash.

BrokenTile.jpg

As I stared, slightly annoyed, at the mess, a favorite maxim of the Greek philosopher, Epictetus, came to mind: “On the occasion of every accident that befalls you, turn to yourself and ask what power you have to put it to use.” Could this array of large and small polygons form a Power Law? With curiosity piqued, I collected all the fragments and measured the area of each piece.

Piece Sq. Inches % of Total
1 43.25 31.9%
2 35.25 26.0%
3 23.25 17.2%
4 14.10 10.4%
5 7.10 5.2%
6 4.70 3.5%
7 3.60 2.7%
8 3.03 2.2%
9 0.66 0.5%
10 0.61 0.5%
Montante plot1.png

The data and plot look like a Power Law distribution. The first plot is an exponential fit of percent total area. The second plot is same data on a log normal format. Clue: Ok, data fits a straight line. I found myself again in the shallow end of the knowledge curve. Does the data reflect a Power Law or something else, and if it does what does it reflect? What insights can I gain from this accident? Favorite maxims of Epictetus and Pasteur echoed in my head: “On the occasion of every accident that befalls you, remember to turn to yourself and inquire what power you have to turn it to use” and “Chance favors only the prepared mind.”

Montante plot2.png

My “prepared” mind searched for answers, leading me down varied learning paths. Tapping the power of networks, I dropped a note to Chance News editor Bill Peterson. His quick web search surfaced a story from Nature News on research by Hans Herrmann, et. al. Shattered eggs reveal secrets of explosions. As described there, researchers have found power-law relationships for the fragments produced by shattering a pane of glass or breaking a solid object, such as a stone. Seems there is a science underpinning how things break and explode; potentially useful in Forensic reconstructions. Bill also provided a link to a vignette from CRAN describing a maximum likelihood procedure for fitting a Power Law relationship. I am now learning my way through that.

Submitted by William Montante


The p-value ban

http://www.statslife.org.uk/opinion/2114-journal-s-ban-on-null-hypothesis-significance-testing-reactions-from-the-statistical-arena