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Дата изменения: Thu Mar 11 22:20:45 1999
Дата индексирования: Tue Oct 2 01:15:31 2012
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Поисковые слова: reflection nebula
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More Correlations in Data
![](startup/hr-envsci202.gif)
Some Final Remarks
And so after this evolution we arrive at a crossroads, strongly
driven by non-equilibrium growth, and we look for solutions about
how to better manage the planet.
Morality vs Economic Decision Making:
Light Bulbs
Much of the current dialogue in environmental studies or management
needs to shift away from belief to a position of knowledge.
The acquisition of knowledge requires gathering good data, analyzing
it correctly, and then forming new questions on the basis of the
data.
The Data Commandments: (Apply them often)
- Always, always ALWAYS plot your
data.
- Never, never NEVER put data through
some blackbox reduction routine without examining the data themselves.
- The average of some distribution is not very meaningful unless
you also know the dispersion. Always calculate the dispersion and
then know how to use it!
- Always exam correlation data for points that could be rejected.
Never reject them just because they are "too far from the line" but rather
examine if poor measurement or some other error is responsible for
these peculiar data values.
- Always present and plot data without any compression in the axis
so that you don't distort the data by fostering an unfair visual
impression. (unless you want to go into politics)
- Always compute the level of significance when comparing two
distributions. Just because they might have different mean values
doesn't necessarily mean they are significantly different. This
is probably the most basic thing to remember from this course.
- Always know your measuring errors. If you don't then you
are not doing science.
- Always require someone to back up their "belief statments"
with data. Change the world. Stop being a passive absorber of
some one else's belief system.
- Always calculate the dispersion in any correlative analysis.
Remember that a correlation is only as good as the dispersion of
points around the fitted line.
- Always remember that unambiguous data resolves conflict when
having a rational dialogue. However, if you live in an irrational
world, all bets are off!
GOOD LUCK
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