Slide 10 of 24
Notes:
The advantages of a gird map are immediately obvious. This is not just a map, it is its mathematical representation based on attribute values. Its most important advantage is that values assigned to the cells can be treated as any other mathematical values. They can be manipulated by using the four basic operations, loged, squared. In our case, the most important use of the grid map is its ability to be added up with other grid-maps and then divided by their number to obtain an average representation.
When graphically representing the average map thus obtained I used the z-score of each cell, instead of its raw score (see slide 11). This method is especially useful for comparing different average maps.