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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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