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I. Distribution Using Dots	II. Distribution Using Census Tract Shading
III. Sir John A. Macdonald CI's census tract and neighborhood	IV. Hsi* vs. Xi* in Vancouver

Presentation of data on a map is a task which concerns both geographers and computer scientists.

In order to display data on maps it is necessary to understand how to manipulate graphics.

Here are four starting points.

• Basic graphics creation from the PHP manual website
• My creation of a simple picture
• Loading a PNG file
• Coloring enclosed regions of a picture

When graphing data it is preferable to use a base map instead of drawing the outlines from scratch. It is both quicker and easier.

Once you load the base map, you have a number of ways to display the data. Here are four that I have used.

• Single dot for each household; click on the map thumbnail and then point at the center of any census tract to get the data value displayed using the title tag
• Variable shading of a census tract to indicate the number of households
• Different colors to indicate the highlighted area versus the others
• Contrasting the distributions of two different sets of data; note the use of a large colored circle for the center of gravity of each group

Your Task

Pick a topic where various subsets of data can be displayed on a map and get it approved by your teacher. There are no limits on what you can investigate. Pick something of interest to the members of your group.

You will need to keep in mind the following.

• Choose a kind of data that can be mapped; the user must be able to select some sort of subset of the data to be displayed
• Pick a geographic area which can be subdivided in some way, e.g., a city, a county, a province/state, a country, a continent
• Find or create a map of the area you plan on working with
• You will need to have at least two files, one for the data to be mapped and one containing information about the map (e.g., a subarea center or a list of the pixels in an area)

As a starting point for your research, you may want to check the City of Toronto's Neighbourhoods Map. However, you are not required to work on Toronto. In fact, you are encouraged to look farther afield.