Resource Mapping

Tuesday, March 06, 2007

COLCHESTER 3325 DB, DAVID VAUGHAN



EXTRACTS FROM COLCHESTER (MAP) 3325 DB

ONE DEGREE BLOCK




Co-ordinates: 25,-34,26,-33


HALF DEGREE BLOCK




Co-ordinates: 25.5,-34,26,-33.5


QUARTER DEGREE BLOCK




Co-ordinates: 25.75,-33.75,26,-33.5


EXACT DECIMAL DEGREES FROM MAP




Co-ordinates: 25.766,-33.750,25.85,-33.666




POSTINGS WITH BROKEN CODE

Hi Everyone,

A large number of POSTINGS appear to be repetative and also to contain broken code which also breaks Blogger's code for the navigation of the site (on the right hand side this gets pushed down to the bottom of the page). If your posting appears to be faulty or repeats itself, I will move these postings into "draft" (so they will NOT be viewable) to keep the Blog working. Please view your postings and check that they are not causing a problem. The usual issue is a URL that is longer than the width of the posting window! The way to get around this problem is to create a "Link" and use some text to point to the link.

The text you use could be...


Link to the original article
Go to the URL
Link to the URL
Available from this URL


Alternatively you can simply put some descriptive text in and then create a link called "here" which is my preferred way.

VERY IMPORTANT - The CSE style guide prescribes that the full URL is provided when referencing, but this can cause the above problems on our Blog site. It would be best to create a Link with the text "Available from this URL".

To illustrate I have prepared below a posting and how it might be prepared and referenced so the links do not break the code.



THE WORLD AS YOU'VE NEVER SEEN IT

In the News & Opinion section of the Sunday Times (South Africa) dated March 04 2007 there is an article entitled "The World as you've never seen it". David Vaughan brought this article into the lab yesterday and it deals with representation of how different countries of the world are perfoming with respect to Wealth, HIV Prevalence, War Deaths and Violent Deaths. The Information is presented as a Cartogram and was produced at the University of Sheffield on their website www.worldmapper.org. The Cartograms are defined as a map in which actual area of a feature (basically a territory) is substituted for a value. Consequently Cartograms are a thematic map in which territories are re-scaled according to data that applies to the territory. Where a territory has a high incidence of say Wealth, its real geographical area will be substituted for the amount of wealth and its area re-drawn. This makes geographical data easy to comprehend. Cartograms are sometimes referred to as an isodemographic map or a value-by-area map [1]. The production of the Worldmapper's cartograms is based on complex algoriths that shrinks and swells various territories using a technique recently published called "Diffusion-based method for producing density-equalizing maps"[2].

In the Sunday Times' article Africa is not doing very well in wealth, but is exceptionally prominent in HIV prevalence, war and violent deaths. Not a very encouraging outlook. I then visited one of the authors of the above technique's personal page where some well prepared cartograms illustrated the following data for each country of the World




You can find more information on the University of Sheffield's World Mapper which can be found here.

The abstract for the orininal article entitled "Diffusion-based method for producing density-equalizing maps" by Michael T. Gastner and M. E. J. Newman can be found here.

You can find more information on various types of Cartograms here.

Reference

[1] Wikipedia contributors. Cartogram [Internet]. Wikipedia, The Free Encyclopedia; 2007 Mar 2, 12:56 UTC [cited 2007 Mar 6]. Available from this URL.



[2] Gastner, MT and Newman, MEJ 2004. Diffusion-based method for producing density-equalizing maps. Proc. Natl. Acad. Sci. USA 101, 7499-7504.

Finally I will change the settings so only the last five articles are posted on the opening Blog page, access to the other postings will be via a link in the Table of Contents on the left hand side.

Please comment if you find anything unclear about this posting.