| Date: | Wed, 2 Dec 2009 10:38:53 -0800 |
| Reply-To: | Dale McLerran <stringplayer_2@YAHOO.COM> |
| Sender: | "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU> |
| From: | Dale McLerran <stringplayer_2@YAHOO.COM> |
| Subject: | Re: Slightly OT: Graphic of Unemployment in the United States |
| In-Reply-To: | <2784D1B1E1F39E4C91787CFA76BC7E9502BC4CC6@DTSEXEVS01C01.rf01.itservices.ca.gov> |
| Content-Type: | text/plain; charset=us-ascii |
|---|
Paul,
I was thinking the same thing and had just located a pdf
file with a number of examples where geographical boundaries
are distorted so that area size represents population or
some other size measure. I believe that such projections
are generally attributable to a cartographer named Walter
Tobler (although I could be mistaken on this point).
Here is the pdf with other similar examples:
http://www.santafe.edu/~mgastner/publications/thesis_compr.pdf
Note that sometimes the shape of these projected map is
itself the salient feature of the graphic. Figure 2.15
on page 35 of the thesis which I have referenced shows
two maps, one in which the size of each state is proportional
to energy consumption and the other in which the size of
each state is proportional to energy production. Shape
differences draw your attention to states which are big
producers and low consumers (and vice versa). Wyoming and
West Virginia immediately stand out for high energy
production and low energy consumption.
I would note that these two maps are imperfect themselves.
The maps are not scaled to have the same total area,
although they should have been. If the plots were scaled
to have the same total area, then one could immediately
identify states which are energy exporters, importers,
or energy neutral. For example, my eyeball inflation
of the energy producers plot to place it on the same scale
as the energy consumers plot would suggest that Pennsylvania
might be energy neutral.
It should be noted that these plots are more difficult
to construct. We probably would not want to map counties
using such projections because of the complexity of the
algorithms for reshaping the plot boundaries. It would
probably be preferable to reduce data to a state level.
But then we would lose much of the information about NYC
as it would be absorbed into a larger geographical
region. However, the effect of unemployment in NYC would
be felt in both the size of the state of NY as well as
in the state unemployment rate.
But just for the record, I do feel that the graphic which
Art pointed to does convey quite well a huge increase in
unemployment and the attendant recession. It is not
meant to show precisely what the unemployment rates are
across the United States. It is meant to show the
increase in unemployment across the United States. In
using an animated graphic, the plot conveys what is
intended.
Dale
---------------------------------------
Dale McLerran
Fred Hutchinson Cancer Research Center
mailto: dmclerra@NO_SPAMfhcrc.org
Ph: (206) 667-2926
Fax: (206) 667-5977
---------------------------------------
--- On Wed, 12/2/09, Choate, Paul@DDS <pchoate@DDS.CA.GOV> wrote:
> From: Choate, Paul@DDS <pchoate@DDS.CA.GOV>
> Subject: Re: Slightly OT: Graphic of Unemployment in the United States
> To: SAS-L@LISTSERV.UGA.EDU
> Date: Wednesday, December 2, 2009, 8:36 AM
> Haven't read the whole thread, so
> pardon if this was mentioned ....
>
> This is similar to the red vs. blue election maps -
> population
> cartograms are much better at proportionally representing
> geographic
> based information.
>
> Mark Newman of the Department of Physics and Center for the
> Study of
> Complex Systems at University of Michigan has a great web
> page on this.
>
> http://www-personal.umich.edu/~mejn/election/2008/
>
>
> Paul Choate
> DDS Data Extraction
> (916) 654-2160
> -----Original Message-----
> From: SAS(r) Discussion [mailto:SAS-L@LISTSERV.UGA.EDU]
> On Behalf Of Ben
> Powell
> Sent: Wednesday, December 02, 2009 7:38 AM
> To: SAS-L@LISTSERV.UGA.EDU
> Subject: Re: Slightly OT: Graphic of Unemployment in the
> United States
>
> I agree, brings to mind the nerve density maps of the human
> body, where
> the
> finger tips are oversize,
>
> Rgds
>
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