People (and Israeli judges) hate ambiguity

One of the big issues that exercises everyone is leakage. Ofwat looked at this dispassionately, as you might expect. The thing is that it costs pretty much the same to fix a leak whether it’s a pinhole or a major mains burst; so we evolved a measure called the “economic level of leakage” (ELL). This was the level of leakage where it was actually cheaper to bring a new water source into supply to compensate for leakage losses than it is to actually go out and track down and repair every leak. We commissioned some research into public perceptions on this matter, and it taught me something important about public opinions. We (well, the consultants we got to do this for us) put together a focus group and asked them “Should all leaks be fixed, irrespective of cost or size of leak?” and then looked at how many people agreed with that. They were then briefed about the ELL measure, with worked examples to explain the concept in terms that anyone could understand. The focus groups were even asked if they understood what they’d been told, and nearly everyone said “Yes”. And then they were asked the original question again – should all leaks be fixed regardless? And despite everything that had been done to explain it, almost exactly the same number of people as before said “Yes”. People prefer their firmly-held beliefs to clear and incontrovertible facts.

 by Robert Day.