Methods Of Data Presentation

Isoline maps - lines on a map that joins places of equal value together e.eg rainfall, rental values

Advantages - can show a large spatial area and changes can be easily identified due to use of fixed intervals. However, construction is more subjective than other forms of presentation and requires a large data set for high accuracy

Choropleth maps - show spacial variations in standardised values I.e percentages by differences in colour and shading.

Advantages - Very commonly used in human geography and relatively easy to interpret for majority of readers. Also, it has a very strong visual impact. However, they give a false impression of abrupt change at the boundaries of shaded units.Choropleth are often not suitable for showing total values and the map assumes the whole region/area has the same value, but there could be variations. Also, It can be difficult to distinguish between different shades.
Variations within map units are hidden, and for this reason smaller units are better than large ones.

Dot maps - they represent the quantity of a given variable using dots of a constant size and locating them in specific points to show the information tied to that location.

Advantages -show the value of a variable within geographical areas and are excellent visual interpretations of geographical distributions. Disadvantages, lots of information needed to construct the map and it is hard to count a large number of dots.

Proportional symbol maps - areas of symbols (circles, squares, triangles are proportional to the values they represent.

Advantages - compared to dot maps it is less tedious counting the dots and compared to choropleth maps the size of the country doesn't matter and the symbol shows the data, on a choropleth map small unit areas can be overlooked.

Flow line maps - show movement between different geographical locations e.g. people. The thickness of lines is proportional to the volume of flow

Advantages - has a clear visual impact with clear location tied to the presentation and can be non-routed (straight lines between places) or routed (line follows actual pathways and transport networks. However, often highly generalised and difficult to extract actual statistical values. Also , it is difficult to show meeting points withought overwhelming the map and can be hard to draw correctly.