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Re: st: Why many things have Normal distribution
From
Yuval Arbel <[email protected]>
To
David Greenberg <[email protected]>
Subject
Re: st: Why many things have Normal distribution
Date
Thu, 29 Aug 2013 13:38:09 -0700
To summarize what everybody mentioned - for very large samples - if
the distribution is not approximately normal - there is something
wrong with the data.
A funny story in this context is the height of candidates for draft to
Napoleon's army.The minimal criteria for drafting was 1.54 meters.
Interestingly, the frequency of candidates with a lower height was
high.
P.S. In the general public many people confuse the median and mean -
because they authomatically assume a symmetrical distribution
On Thu, Aug 29, 2013 at 1:26 PM, Yuval Arbel <[email protected]> wrote:
> Here is a link to Mario Livio in wikipedia:
>
> http://en.wikipedia.org/wiki/Mario_Livio
>
> On Thu, Aug 29, 2013 at 1:21 PM, David Greenberg <[email protected]> wrote:
>> LOts of social indicators are highly skewed, but parameter estimates (such
>> as regression coefficients) may closely approximate a normal distribution
>> when one has large samples, because of the Central Limit Theorem. David
>> Greenberg, Sociology Department, New York University
>>
>>
>> On Thu, Aug 29, 2013 at 3:58 PM, Yuval Arbel <[email protected]> wrote:
>>>
>>> Vinicius,
>>>
>>> I'm not sure that I have the full answer. However, an interesting book
>>> that can recommend in this context is written by a well-known academic
>>> physicist named Mario Livio.
>>> The name of the book: "Is God A Mathematician?"
>>>
>>> The author's claim is that the normal distribution was discovered in
>>> the natural sciences in the 16 th century. When you make many
>>> temperature measurements and write the outcomes - you will find they
>>> are normally distributed.The first person who found that the normal
>>> distribution can be applied to social problems and physical human
>>> features is Adolf Katle who lived in today's Belgium.
>>>
>>> P.S.The author implies that the name given to the normal distribution
>>> as the "Gaos Bell" (named after the prince of Mathematician) is not
>>> entirely justified
>>>
>>>
>>> On Thu, Aug 29, 2013 at 12:11 PM, Roger B. Newson
>>> <[email protected]> wrote:
>>> > I would guess that it is because so many things are equal to the sum of
>>> > a
>>> > large number of weakly-dependent terms. Or, in the case of a lognormal
>>> > distribution, so many things are equal to the product of a large number
>>> > of
>>> > weakly-dependent factors. I don't know how string theory comes into all
>>> > this.
>>> >
>>> > Best wishes
>>> >
>>> > Roger
>>> >
>>> > Roger B Newson BSc MSc DPhil
>>> > Lecturer in Medical Statistics
>>> > Respiratory Epidemiology and Public Health Group
>>> > National Heart and Lung Institute
>>> > Imperial College London
>>> > Royal Brompton Campus
>>> > Room 33, Emmanuel Kaye Building
>>> > 1B Manresa Road
>>> > London SW3 6LR
>>> > UNITED KINGDOM
>>> > Tel: +44 (0)20 7352 8121 ext 3381
>>> > Fax: +44 (0)20 7351 8322
>>> > Email: [email protected]
>>> > Web page: http://www.imperial.ac.uk/nhli/r.newson/
>>> > Departmental Web page:
>>> >
>>> > http://www1.imperial.ac.uk/medicine/about/divisions/nhli/respiration/popgenetics/reph/
>>> >
>>> > Opinions expressed are those of the author, not of the institution.
>>> >
>>> >
>>> > On 29/08/2013 19:27, Marcos Vinicius wrote:
>>> >>
>>> >> hello,
>>> >> Yesterday someone asked me a philosophical question :Why many things
>>> >> have
>>> >> Normal distribution ( or at least approximately)?
>>> >> My answer: It is a type of symmetry we observe in nature.. maybe a
>>> >> String
>>> >> Theory specialist may have a technical answer.
>>> >> How do you answer that question?
>>> >> CLT maybe ?
>>> >>
>>> >> Regards,
>>> >> Vinicius
>>> >>
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>>>
>>>
>>> --
>>> Dr. Yuval Arbel
>>> School of Business
>>> Carmel Academic Center
>>> 4 Shaar Palmer Street,
>>> Haifa 33031, Israel
>>> e-mail1: [email protected]
>>> e-mail2: [email protected]
>>> You can access my latest paper on SSRN at:
>>> http://ssrn.com/abstract=2263398
>>> You can access previous papers on SSRN at: http://ssrn.com/author=1313670
>>> *
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>>
>>
>
>
>
> --
> Dr. Yuval Arbel
> School of Business
> Carmel Academic Center
> 4 Shaar Palmer Street,
> Haifa 33031, Israel
> e-mail1: [email protected]
> e-mail2: [email protected]
> You can access my latest paper on SSRN at: http://ssrn.com/abstract=2263398
> You can access previous papers on SSRN at: http://ssrn.com/author=1313670
--
Dr. Yuval Arbel
School of Business
Carmel Academic Center
4 Shaar Palmer Street,
Haifa 33031, Israel
e-mail1: [email protected]
e-mail2: [email protected]
You can access my latest paper on SSRN at: http://ssrn.com/abstract=2263398
You can access previous papers on SSRN at: http://ssrn.com/author=1313670
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/faqs/resources/statalist-faq/
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