What is Map Analysis
Map analysis involves the reading and interpretation of the content of a map. This entails decoding the map symbols to derive their meanings and also understand the message or information those symbols convey
to the map user. As stated by Ajayi (2003), map reading is “the ability to recognise the conventional signs and symbols as used on maps and their descriptions in words of the area mapped with the aid of signs and symbol”. In addition, map analysis is whereby a study is made regarding map types i.e. political maps, military maps, contour lines etc., and the unique physical qualities or elements of a map i.e. scale, title, legend, etc.
Map Analysis Tasks
Usually, map analysis is accomplished by executing a number of tasks. Basically there are four (4) broad tasks involved in map analysis. They are:
Enumeration, and Usually, the first two tasks mentioned above (i.e. classification and delineation) are first carried out in that logical order before any of the remaining last two (i.e. enumeration and measurement). Each of the tasks is discussed below.
This involves assigning objects, features, or areas to classes based on certain criterion. There are about three levels of confidence or precision that can be achieved in classification. These are: (i) detection, which is the determination of the presence or absence of a feature on a map. (ii) recognition, which involves assigning a feature to a general class. For instance, we can generally classify a feature as a road. (iii) identification, which means we have enough details about the identity of an object or feature that we are confident enough to place it in a very specific class. For instance, based on available details we can confidently say a particular road is a secondary (Trunk B) road instead of just classifying it generally as a road.
High level or more precise classification of features enables us to do more accurate and precise map analysis. In other words, the higher the level of classification, the more detailed and more accurate will be the level of map analysis we can do.
This refers to outlining or placing boundaries round regions or areal units observed on the map. A typical example is the delineation of separate classes of land use or vegetation
This refers to listing or counting of discrete items visible on a map. For example, on a large scale map showing a portion of a city we can count or take a census of the number of individual houses, boreholes, bus stops, or petrol stations in the area.
This refers to the physical quantitative measurement of certain variables such as length (distance), height, volume, perimeter and area. For instance, on a topographic map, we can measure and calculate the distance between two places, the height of the peak of a hill or mountain, or the area of a lake.