Looking at the last World Championship,
Gold Coast 2018, we can see the triathlon outliers: The winner of the female junior elite category;
Hungary could spread its athletes’ data and it can be on the outskirts of the winning
culture with its male athlete winning the junior category. Cecilia
Ramirez is clearly outside of Mexican expectations statistically. She is an outlier.
An outlier is an
observation that lies outside the overall pattern of a distribution (Moore and
McCabe 1999). Usually, the presence of an outlier indicates some sort of
problem. This can be a case which does not fit the model under study, or an
error in measurement.
Outliers are often easy
to spot in histograms. For example, the point on the far
left in the above figure is an outlier.
A convenient definition
of an outlier is a point which falls more than 1.5 times the interquartile range above the third quartile or
below the first quartile.
Outliers can also occur
when comparing relationships between two sets of data. Outliers of this type
can be easily identified on a scatter diagram.
When performing least squares fitting to data, it is
often best to discard outliers before computing the line of best fit. This is
particularly true of outliers along the 
direction, since these
points may greatly influence the result.
direction, since these
points may greatly influence the result.
The study of outliers gives
unique information. The case of the Italians
immigrants living in Roseto, Penn has been studied, they were outliers when they
first came to Pennsylvania; the coronary artery disease was no so prevalent as in the
other immigrants from other ethnicities. At the end of the study, the way of living
made the difference.
It seemed like a virtual
fountain of youth, with a heart attack mortality rate roughly half the rate of
every surrounding community. Same water, same neighborhood, same occupational
mix, same income level ranges, same races. So what was the difference and why?
Well, you
had to ask the Rosetans for the answer, and the next question you ask should
be, Who are the Rosetans?...
Part of the bargain:
Rosetans, regardless of income and education, expressed themselves in a
family-centered social life. There was a total absence of ostentation among the
wealthy, meaning that those who had more money didn't flaunt it. There was
nearly exclusive patronage of local businesses, even with nearby bigger shops
and stores in other towns. The Italians intermarried in Roseto, from regional
cities in Italy. Families were close knit, self-supportive and independent, but
also relied...in bad times...on the greater community for well-defined
assistance and friendly help…
In 1963, these
investigators made a prescient observation: they believed that as Rosetans
became more Americanized (meaning less close, less modest and less
interdependent), they would also become less healthy. The wearing off of the
now famous "Roseto" effect would be apparent within a generation. And
so it was.
A relatively
recent (1992) survey, as published in the American Journal of
Public Health, confirmed this sad prediction. The officials of the AJPH, no
doubt beguiled by Roseto's fate, descended on the town yet again. Again the
investigators rifled through the death records of Roseto, and again they
compared them with the surrounding towns of Nazareth and Bangor. The result:
the Rosetans now suffer equally from the ravages of heart disease as every
other town does, in the vicinity or not.
Cecilia is not doing the
same as the rest of the Mexican triathlon culture. Education for Outliers has taken place daily. Does it exist? We have mentioned it in the previous
post. Generic education should continue
if we want to continue learning; otherwise, we are going to finish like the
Rosetans, losing the advantage. Cecilia is a real outlier as well as the kids
training with her. We have written about it:
16 avr. 2014
Triathlon and Regression Toward the Mean
This is a very tricky subject. I have touched it several times but never went over. It is the main reason why we have to choose our partners; we can become as the ones we critized if we interact with them for a long time:
In statistics, regression toward (or to) the mean is the phenomenon that if a variable is extreme on its first measurement, it will tend to be closer to the average on its second measurement—and, paradoxically, if it is extreme on its second measurement, it will tend to have been closer to the average on its first.[1][2][3] To avoid making wrong inferences, regression toward the mean must be considered when designing scientific experiments and interpreting data.
This concept has not a translation to Spanish. IT IS SCARRY! This is a basic concept when we think about things scientifically; it is a sin ne quo non in science. It is very important what could happen due to luck or to what we consider a trend in science:
The concept of regression comes from genetics and was popularized by Sir Francis Galton during the late 19th century with the publication of Regression towards mediocrity in hereditary stature.[6] Galton observed that extreme characteristics (e.g., height) in parents are not passed on completely to their offspring. Rather, the characteristics in the offspringregress towards a mediocre point (a point which has since been identified as the mean). By measuring the heights of hundreds of people, he was able to quantify regression to the mean, and estimate the size of the effect. Galton wrote that, “the average regression of the offspring is a constant fraction of their respective mid-parental deviations”.
https://deportes.televisa.com/otros-deportes/videos-cecilia-ramirez-experiencia-en-triatlon/
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