It should contain only the country and latlong data themes. Choose a color ramp scheme Due to the way in which the data is reported in the table, it may be difficult to compare values for different counties since there are differences in population and area. For this reason, you should normalize your data. When you click Apply , notice the changes to the View . Also, notice the changes to the values of the legend in the Table of Contents Look at the map.
Classification is the process of placing data into groups, and is central to mapping.
Classifications are human creations, and do not exist in reality. However, in order to make sense of a large amount of spatial data, it is necessary to impose a criteria to classify the data. The goal of classification should always be to characterize the natural tendencies of the data, and should not be based on meaning . Obviously if you are working with large amounts of data you would not want each feature to have its own class. Conversely, only having two classes may not allow you to appreciate trends within the data.