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Bivariate Choropleth and Proportional Symbols

In the first part of this lab, we used proportional symbols to represent positive and negative values in job increases/decreases in the USA. 

Because there were negative values in this data set, I created a new map to "fix" the data. In this new map, I created a new field and copied the negative job loss data. I then used the Calculate field data and multiplied it by one to make it positive. Lastly, I overlaid both maps on the data and was able to accurately represent the increase and decrease of jobs in the USA by state. 



 In the second part of this lab, we delved into how to prepare data for a bivariate choropleth map, choose colors for the legend, and create a good layout. 

I created three separate fields to analyze the data: Class Obese, Class Inactivity, and Class Final. I used the symbology tool to create 3 Quantile for the Obese and Inactivity classes and used each quantile to set the three classifications in the fields I created using the Select by Attributes tool to first select each quantile range. I then used the Calculate field tool to convert each range into 1,2,3 or A,B,C classifications. I could then add these two fields together in the Class Final, to then use this field to map the legend. 

I chose to go with one of the suggested bivariate color schemes. I created the bivariant legend using the colors based on high-density colors that are distinct and dark. I keep the legend on the lower-left corner and added labels to make it readable. I used arrows and axis labels to explain the data, as well as providing a simple title for an overview.

A bivariate choropleth map allows an analyst and a reader to compare two different variables, and possibly determine a correlation. The bivariate legend allows a visual correlation to be determined between the two variables. If there is a positive correlation at a set geographic point, we will see the hue in C3 as correlations increase from left to right and bottom to top. One can see a high correlation, of Obesity and Inactivity, on the map in the southwest-central region, when using the bivariate choropleth map. 

Bonus Map




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