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Re: End of this phase

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Wed, 14 Sep 2011 22:07:15 +0200

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 ```On Wed, 14 Sep 2011 14:46:03 -0400, Ray Denenberg wrote > From: Edward C. Zimmermann > > The last digit in scientific notation is typically used to present an > > "estimation". > > I'm trying to visualize this and I can't. Can you give an example? > y193e1 is 1930 with 10 year precision, e.g. 193x y193.9e1 is 1939 with decade precision, the 9 in 1939 is "estimated" y19e2 is the 1900s, e.g. 19xx y19.5e2 is 1950 with century precision, the 50s is "estimated" y19.50e2 is 1950 with century precision and the year "1950" is "estimated". y19e2 and y19.00e2 as one can see are NOT the same. y19.00e2 is an estimated year 1900 with decade precision. Why the estimate? There are loads of reasons.. I might know that an event took place in the 1950s and "estimate" it was 1957. I can write this as y195.7e1 This is not the same as approx 1957.. and it not the same as uncertain.. I am saying that I know it was in the 1950s.. its within my measurement precision.. Think of a thermometer with ticks for every degree.. One can read the degree.. and in between.. its an "estimate".. When we start to talk about historical events such as the "Big Bang".. and say it was 13.7 billion years ago.. we say.. that it was 13 billion years ago.. and the 0.7 billion is an estimate.. Sometimes we don't have an estimate.. example "Heat Death" which is often said to occur y1e150 from now...   > > Changes: > > y17e7 is the year 170000000 with precision of 10000000 years > > y17.3 is the year 173000000 with precision 10000000, e.g. 3000000 is > > Did you mean to say > > > y17.3e7 is the year 173000000 ..... Yes.... -- Edward C. Zimmermann, NONMONOTONIC LAB ```