Predominance is a form of mapping that can be used to compare multiple attributes within a dataset and show the largest (dominant) value on the map. This is a method of identifying and visualizing new patterns within datasets. My feeling is that MapInfo Pro could benefit from having this capability as part of the built-in capabilities. I would be interested to hear from other users as to if and how they produce these forms of maps in MapInfo Pro, whether they feel this development would be worthwhile, or if I am a solo voice in the distance.
I will try and provide a little more context and some explanation of how I am currently producing these outputs using MapInfo Pro below to assist the conversation.
With more and more data becoming available, the question of "which is the dominant attribute" from a row with multiple attributes, and then displaying this attribute on a map is a valuable method for analyzing data. The capability is provided as standard by a number of other spatial analysis tools.
A predominance map can be applied when there are multiple columns of data that share a common subject and unit of measurement. By using predominance to analyze the multiple columns of related data, a user can determine which column contains the highest, or predominant, value for each geographic feature or reference.
An election map (like the one below by ABC News for the 2020 US Election) is a simple example of a predominance map. On a State-by-State basis, it displays which of two or more candidates have the highest total vote count.
Presently to use predominance in MapInfo Pro, the data needs to be prepared outside of the tool in some form of data analysis tool (can be as simple as Excel). Once the analysis is completed, the data can then be imported into MapInfo Pro and linked to the relevant geographic object to enable the result to be displayed. The relevant value for the dominant variable can also be incorporated to enable bivariate thematic mapping.
If the dominant value is noted as part of the data preparation, MapInfo Pro could allow the dominant value to be used in displaying a region object in a bivariate manner by using the dominant category to colour the object and the dominant value to be reflected in the colour density/transparency (if this capability was present).
The example below determines which Profession category is dominant based from a typical demographic group of variables - Census data in this case - while the map displays the dominant variable category by region. The red fields are generated in Excel.
I have provided some further examples below (base data - prior to preparation - and final map images) of the application of predominance developed using Excel and MapInfo.
Preparation of the data to determine predominance was done using Excel formulas (to deliver fields similar to the red fields in the Profession example above) and then this data was imported into MapInfo Pro and linked to the appropriate geographic object (point, line, or polygon) using a unique identifier.
These examples include:
- Determining which Age Band is dominant from a typical demographic dataset (map displays dominant category by region)
- Determining which Household Income Band is dominant (map displaying this as a bivariate thematic at a point level using the dominant category for the colour and the proportion value of the dominant category for the size of dot)
- Determining which brand/model of luxury SUV had the most sales (map displays dominant brand/model by region)
- Results from the Agriculture Census (example data shown) is another potential application where the dominant category of produce for an area could be determined and then displayed on a map
Given that I am sure all users of MapInfo Pro have examples of data that could benefit from the use of predominance analysis, I think it "Predominance" deserves consideration for inclusion in MapInfo Pro and would be a beneficial enhancement in the analysis and visualization capabilities available to users.
Look forward to comments from the Community.
Principal Consultant - Location Analytics & Data
Sydney - Australia