This week's lab module for Computer Cartography 5007L focused on enhancing our understanding of the use of choropleth maps as well as proportional and graduated symbology.
A choropleth map is a type of thematic map that is used to present data in relative values such as percentages or rates per capita. Choropleth maps are not to be used when mapping raw data counts as this will result in a misleading representation of the data. For instance, if you wanted to map cases of disease infection by state using raw data totals in a choropleth map this would result in larger more populous states appearing as though they have the highest case rates which would only be a partial truth. If you made the same map with normalized data by dividing total cases by the population of each state your map would tell a different story with the large more populous states likely showing to be less impacted.
In this week's lab, we were tasked with creating a choropleth population density map of Europe with graduated or proportional symbols for wine consumption. This involved choosing an appropriate color ramp to present our population density data and choosing the right classification method to present it. For my map, I chose a sequential single hue 5-class orange ramp and my method of classification was natural breaks. I think the natural breaks method did an adequate job of maximizing class differences. I chose the sequential 5-class orange ramp scheme using Color Brewer ensuring that the colors would be colorblind safe. I chose graduated/range-graded symbols for my wine using a wine glass picture symbol for customization. I think my choice of wine glass could have been better as the color does not offer an adequate contrast to the population density colors.
I created my map using ArcGIS Pro and utilized SQL expressions to manipulate the data for optimal presentation in both my main and inset maps. I also converted my labels to annotation in both maps to appropriately place my labels. The most challenging part of creating this map was getting all the SQL expressions right and placing the labels appropriately. I thoroughly confused myself a few times but was able to regain my bearings.
Below is my final map after numerous revisions.
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