How to help your readers' intuition, or lack thereof, when talking about probabilities

Bayes' famous theorem is widely regarded as the most important theorem in statistics. But that doesn't mean that it is easy to understand or interpret; not by any means.

Today, trying to come to grips with it myself, I stumbled on a vital piece of information for any technical writer or into-English technical translator who wants to make any text that mentions probabilities more accessible to their readers.

Fortunately, you can use this tip whether or not you've managed to understand the theorem, so feel free to jump to the shortcut.

Optional: Want to know more about Bayes' theorem?

Here are three links:

• An Intuitive (and Short) Explanation of Bayes’ Theorem
• High-speed intro to Bayes's rule
• Bayes theorem, the geometry of changing beliefs
• The Bayesian Trap by Veritasium.

Shortcut

From An Intuitive (and Short) Explanation of Bayes’ Theorem:

People prefer natural numbers. Say “100 in 10,000″, or something similar, rather than “1%”. This helps people work through the numbers with fewer errors, especially with multiple percentages (“Of those 100, 80 will test positive” rather than “80% of the 1% will test positive”).

Who are you talking to? An expert or a member of an elite

We all know that effective translation, like effective writing, typically hinges on a good understanding of the target readership and a clear idea of what the text and its translation are intended to achieve. But that's once you have the job. What about the phase where you're still pitching your services to the client, especially if the person you are pitching two comes from higher up the management chain than the person or team who will eventually manage the work?

I recently stumbled upon this excellent piece by Rob Henderson entitled Experts and Elites Play Fundamentally Different Games.

Henderson's piece explains all sorts of situations that I observed over the years and many in which I was personally involved.

I now see more clearly why I had so much trouble and for so long attempting to convince clients that it wasn't "straight translations" they needed but client- or target reader-centred adaptations. And when I started achieving a measure of success, it was probably partly because by then I was talking to "expert" technical journalists rather than high-flying engineers who saw themselves as members or aspiring members of the elite.

Goodness; and to think that we had to wait for 2025 to find someone who could explain these things to us in relatively simple terms.