Data Maps

Dear Mr. Tufte,

I am looking for some feedback on the use of interactive data
maps on the web. I’m experimenting with a ‘histogram key’ for b/w data maps.

My concern here is that the use of quasi-continuous shading
might lead to ‘eye bobbing’ between the data map and the
histogram key.

More experimental is the use of color data maps.

In this case I’m hoping that interactivity is the path to
understanding, at least for the mixing of two colors.

I would be grateful for any criticism you or your readers could
offer.

I look forward to your seminar in Portland later this month.

Sincerely,

Joe Meyer