Many so called ‘analysis’ drawings consist of mapping data – most often during site and context analysis phases of a design project. Both data and analysis are important and critical for understanding how you work with a site, however, it’s important to understand the different between the two. A survey of elements (e.g. building uses, bus stops, site materials, light & noise levels, points of access) tells you what is there and when mapped tells you about their geographical distribution. This information is useful but it is not analysis. To understand analysis, imagine that what you have to show is something that is not immediately obvious or visible. This means trying to answer questions such as ‘why are there x number of y’ or ‘why is x distributed in a particular pattern’. Whereas we can see something like bus stops or commonly used materials you cannot immediately see its causes or effects. There may be economic, bureaucratic, or historical reasons behind what you see. One ‘trick’ to try to get into the realm of analysis is to correlate different spheres of data. You might generate a sun path diagram that demonstrates the distribution of daylight; you might map local area uses. So far this is data. But if you find a link you have begun a form of analysis. An Example: walking to work on a cold winter’s day I noticed that everyone was walking on one side of the street and not the other. They were walking on sunny side of the street, the north side, because it was receiving sunlight whereas the south side was in shadow and much colder. It also turned out that certain kinds of shops seemed to prefer premises on the sunny side rather than shaded side and so all the cafés were on the north side of the street. I noted a possible explanation of how light influenced where people walked and how light, and also footfalls, influenced the location of particular uses. Correlated or linked data leads to analysis and explanation.
Another way to think about this is that data describes and analysis explains. I can describe the colour, dimensions and form of my mobile phone and lists its features (data and description) but I can also explain how its design is influenced by contemporary notions of technology, available materials and current fashions for touch sensitive interfaces (analysis). Getting beyond data and description and into analysis will reveal more about the context or project your are examining and your response and reaction to it will be that much more informed (and less about the surface image of what you are looking at).