Thinking-sphinx and relevance or similarity score

Does someone know if there is a way to get the raw relevance or similarity score between a q开发者_StackOverflow社区uery and a result when using sphinx in general or thinking-sphinx as a wrapper? Any help is greatly appreciated.

@results.each_with_weighting do |result, weight| # ... end

from the comments on http://railscasts.com/episodes/120-thinking-sphinx