Tag Archives: probability

The precautionary principle

A good topic for blog posts in our general theme area of “probability” for this week might be the precautionary principle.  This idea, which has legal force in some countries, has several forms: one of them is that “if a proposed action is suspected of causing a risk to the environment, then  those proposing the action need to demonstrate that it does not propose a risk; those opposing the action do not need to demonstrate that it does pose a risk.”

Here is a basic scientific paper on the principle


and a link to an important early consensus statement

Wingspread Statement

The precautionary principle is appealing, but there are some obvious problems with it, for instance: What counts as “demonstrated” absence of harm?  What if our choice is not between “risk” and “safety” but between two courses of action both of which are “risky” in different ways?

You could post about the application of these ideas, and its relation to more probabilistic methods of risk assessment, in any one of several contexts: GMO foods, vaccines, cell phones and brain cancer, climate change…


Blogging theme week 11

This week marks the beginning of the third and final blogging period.  The instructional team has not yet reviewed and fixed the grades for blogging period 2, but simply based on the number of posts it is clear that many of you will need to take advantage of the way the scoring system works to raise your blogging grades in this final period. We had a good discussion about blogging in class last Wednesday and the handout from that session is available here if you missed it.

For this week my suggested theme is “Probability in the Media”.   Find a media item (a news article, a YouTube clip, a web page, whatever) that uses probability in relation to an environmental theme, and analyze the ideas using the concepts that we have discussed in class (conditional probability, payoffs, expectations and so on).

Remember that, as always, the theme is only a suggestion.  You are welcome to post on any relevant topic, including one of the earlier suggested themes.  Here is a list of those:


Scientific American article about probability and medicine

Here’s an article from Scientific American which gives a great review of the material we covered in class yesterday (Unit 3.3) in the context of medical testing.


The reference is
Gigerenzer, Gerd and others. April 2009. “Knowing Your Chances: What Health Stats Really Mean.” Scientific American,   44–53.

The notes for section 3.3 have some quotations from Gigerenzer’s book which is related to this article.