I'm looking for a solution for how to represent two different values on a single marker on the map.
Background: I am building a real estate site where a key feature is showing results based on travel time, not distance. i.e. based on how long it takes on the train, bus or car instead of how many miles on kilometres it is.
In the current solution the user can provide more than one travel destination (e.g. within 30 minutes from office A and within 20 minutes from office B) however on the results map we show marker colour based on travel time to office A only.
I'm seeking ideas for how to represent visually travel times for two or more locations - or at least for the two. As an example of ideas:
- Use an inner circle and then an outer ring to represent the colours for the two locations
- Use a single colour and it represents the "combined" travel time for the two. e.g. if both are 15 mins or less, show it as green, if one is 15 minutes and the other 20 then show it as yellow, etc.
I worry if solution one will show up well enough - especially for the locations with smaller dots - and I worry that solution two is not intuitive.
By the way, I experimented with color brewer combinations but couldn't find any that looked good for this purpose, so I've stuck with the green-yellow-orange-red approach to coloring.
Here is the map legend: