But it said this had "only a low probability of occurrence" and more work was needed.

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Thus, by deliberately disrupting all redundant safety systems, saboteurs can cause a severe event that would have had only a very low probability of occurrence if left to chance.

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This led him to calculate that the information content of any event was proportional to the logarithm of its inverse probability of occurrence. (Unlike many popular-science books that eschew equations, Mr Vedral includes a couple and tries his best to explain them to the reader.) What does the equation mean?

ECONOMIST: Information theory