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 Post subject: Question on exponential growth
PostPosted: Tue Apr 12, 2011 5:08 pm 
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In my field of work I sometimes see upward-sweeping "ski-slope" graphs of growth, plotted per month. This is commonly referred to as "exponential growth."

On some of these graphs, though upward sweeping, the growth rate per month is declining. To me, that's not exponential growth, and I think such plots are mischaracterized.

According to the Wikipedia entry on exponential growth, it says it occurs "when the growth rate of a mathematical function is proportional to the function's current value." In this version, the growth rate must increase each period.

I thought the growth rate stayed the same -- e.g., compound interest.

So, I'm confused.


Last edited by Eboy on Tue Apr 12, 2011 6:02 pm, edited 1 time in total.

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 Post subject: Re: Question on exponential growth
PostPosted: Tue Apr 12, 2011 5:56 pm 
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Quote:
exponential growth


As a risk assessor ( I have the hideous job of also being a risk manager)

That term is BS.

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lane h. can be reached at laneman@verizon.net
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 Post subject: Re: Question on exponential growth
PostPosted: Wed Apr 13, 2011 12:00 am 
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Who said, "The greatest shortcoming of the human race is our inability to understand the exponential function."?

At the moment exponential decay is more newsworthy.


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 Post subject: Re: Question on exponential growth
PostPosted: Wed Apr 13, 2011 12:09 am 
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According to Wikipedia Albert Allen Bartlett.

From the article:

He regards overpopulation as "The Greatest Challenge" facing humanity, and promotes sustainable living. Bartlett opposes the cornucopian school of thought (as advocated by people such as Julian Lincoln Simon), and refers to it as The New Flat Earth Society

So not only is the good professor given to hyperbole he's also impervious to irony.


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 Post subject: Re: Question on exponential growth
PostPosted: Wed Apr 13, 2011 12:51 am 
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Eboy wrote:
Eboy says:
"On some of these graphs, though upward sweeping, the growth rate per month is declining. To me, that's not exponential growth, and I think such plots are mischaracterized."


Logistic curve perhaps?
http://en.wikipedia.org/wiki/Logistic_function


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