Here's a nice piece about parks in cities (Ontario to be precise). You might have thought that proximity was the most important thing - the nearer the better. Not so! and the results, which I leave you to discover, carry a clear message to urban planners.
I like the use of a formal assessment measure (the 'Environmental Assessment for Public Recreation Spaces' instrument).
One disappointing feature of the study was the response rate - 61%. Part of the problem was that householders had to complete activity diaries, to be collected after 10 days by the researchers. In a single-visit survey, with excellent interviewers, I'd be looking for a response rate of over 80%.