Does a Bayesian "p > 0.5" translate as "probably"?

This is motivated by my desire to translate Bayesian conclusions such as I arrive at here into plainer language. If I find that the median of the posterior distribution over some parameter \theta is less than m, then I could say,

It is more likely than not that \theta < m.

But I would much rather make the plainer statement that:

\theta is probably less than m.

How do people feel about this?

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This probably (sorry) doesn’t answer your question directly, but there has been some work done on the “perception of probability words”, with an interesting history. Here is one short summary I found with a quick search.

Personally I think your statement is reasonable, but it seems like respondents in these surveys tended to place a higher threshold on “probably” (and “probable”).

You might be able to find more applicable or modern results by following the links in the page above, or with a more thorough search than I did…

[edit: I just stumbled on this Wikipedia entry, which might have some further rabbit holes to follow - Words of estimative probability - Wikipedia ]

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Thank you, Mark! This is very much the sort of thing I’d hoped for. It gives me a little ammunition in case reviewers object, but also serves as a caution, given that only a few people in that interactive graphic put ‘probably’ at 50–51%.

I get into this here where I suggest that the word “probably” is fine to use as long as it appears in language such as “the drug probably (0.54) causes a reduction in blood pressure” and 0.54 is the current posterior probability and the prior and data model are documented nearby.

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This seems an excellent general practice to adopt. In my particular case here, the parentheses would have to read somewhat mysteriously (0.5+\epsilon); but a footnote could also serve the same purpose.

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