One of the greatest challenges in risk and evidence communication is how to communicate the inherent uncertainties in information and numbers.
These uncertainties can be of many types, and there may be several different ways to communicate each.
For example, inherent and unpredictable randomness or chance causes what is known as aleatory uncertainty. This kind of uncertainty is very common when communicating the chance of an event happening in the future. Uncertainty that stems from our lack of knowledge about things that are theoretically knowable is known as epistemic uncertainty. For almost all projections about the future, or our understanding of the past and present, there are large amounts of epistemic uncertainty (Spiegelhalter, 2017; van der Bles et al., 2019).
There are also different levels of uncertainty: it could be uncertainty directly around the number or fact being communicated, or deeper uncertainty around the evidence for that number or fact.
As reviewed in, for example, (van der Bles et al., 2019) and (Gustafson and Rice, 2020), different formats of communication, of different kinds of uncertainty, and to different audiences, can all potentially create different responses in the receiver of the uncertainty information.
If the audience are making decisions based on the uncertain information, then the effects of that communication could have profound implications for the decision-making process. For example, by affecting people’s understanding of the likelihood of an event, their trust in the fact or in the communicator, or the weight that they might put on the fact in their decision-making.
All of this means that careful research is needed to understand these potential effects in a broad range of situations.