Cartography Module 5 - Choropleth and Graduated Symbols

 Greetings,

Welcome to Choropleth week. This is the type of thematic map that we are dealing with this year. The subject area is central Europe and we are looking at two primary factors. First and underlying everything, population density, which is the blue hued sequential color scheme on the map below. Second is a look at wine consumption by country through the use of graduated symbols highlight a consumption range of liters per capita. 

The overall objectives of this module are to appropriately employ both the choropleth and symbology methodology. This is accomplished while also working with a data set that has more information than needs to be or can be displayed. For example, there are several countries of negligible size and wine consumption when viewed at the scale provided. As such they are omitted from the presentation, also some known outliers have been removed. 

What's left is a map that explores data standardization and display customization while employing all of the standard map elements. My overall goal was to maximize the size presentation of the subject countries while also providing as clear a picture of the two mapped factors. The final map is presented below. 

Looking at the map, the colors are what we care about. The white to blue and red. That is your mapped data, the gray scale underlying everything else is all background or supporting information kept slightly out of focus. You can see that some of the information becomes jumbled, so an inset is also employed to highlight a conglomeration of numerous countries together. 

Also as an aside, but learning point for the module, you can see on the bottom, slightly left, the projection information. Why is this important? 

Well,  the Albers Equal Area Conic projection is particularly good for areas such as this because as its name suggests it retains the area for the region. Possibly more importantly it has relatively little distortion between the standard parallels used to make out the conic shape. This is better suited to wider regions like our section of Europe. We have a larger east-west section than north-south. Preserving the area is also particularly important because of using the population density which is a measure of population across Square Kilometer, so we want the countries themselves which are the enumeration unit to have as accurate an area as able. Then our final map also should look undistorted, thus this projection provides a good balance even though shape and conformality aren’t strictly maintained. By providing the projection on the map an observer can then glean that information on how this image and data was processed.

Thank you.

v/r

Brandon