[data visualization application] draw bivariate mapping map (with R language code)

Bivariate Choropleth Map

In mapping , We often use a single variable for mapping , Of course , The results presented in this way can well represent the characteristics of our research ( Such as income 、 House price, etc ) The change or specific situation of , Here's the picture ：

Single variable mapping map

First , Let's briefly explain the meaning of bivariate mapping through the following figure ：

1. First, we create a single variable 3 Level order color matching color system . Colors start with lighter neutral colors , Represents the minimum value of the first variable . The color system gradually darkens , And towards saturation of hues representing higher values . The intermediate color should have the same hue as the background color , But its saturation should be lower and its brightness higher , as follows ：

   

2. According to the first step , Let's create another color system , Colors have similar meanings , as follows ：

                                   

   

3. We will choose 6 The colors are rotated and stretched , You can get The following effects ：