Last week I was amazed to read an article in the Guardian which talked about a pub "cutting energy costs" by switching off their lights and using candles instead. Throughout the article there was absolutely no mention of the fact that this could save the pub probably no more than 1-10p (without even factoring in cost of candles).
Why is it not well known that lightbulbs, especially LED lightbulbs, don't actually consume that much energy?*
I recently ran a couple of workshops on statistical literacy and science communication with people from different academic backgrounds and one thing that came up was effect size.**
When people read in the newspaper, about say bacon being linked to cancer, what do people actually do with this information? Do they eat less bacon as a result? Because even if bacon is linked to cancer, you have to eat an awful lot of bacon for there to even be a small risk and it still won't get anywhere near to the effect size of smoking.***
So one theory we came up with is that people essentially just work off vibes. That is, in order to understand the world they categorise things into simple "good" thing or bad" thing. Seeing the world this way is much simpler and easy to remember than effect sizes. We all doit. There are just so many things in the world we have to remember so we have to find some simple heuristics to help us.
For example: Fruit, fish, red meat, vegetables. I am pretty sure in your head you already categories these things into "good" and "bad".
If you have ever been on a diet, counting calories is a real pain. To do it properly you have to not only look up the calories of each ingredient but weigh them out. This is why people often use a simple good/bad heuristic to make decision when they are on a diet. Fruit and vegetables are "good" so people on diets eat lots of them, even if that fruit is orange juice (which can have more calories than coke).
If you think this is easy and it's just that people are stupid, how many calories would you say are in a large Domino's garlic and herb dip? And even if it is easy for you to quantify and remember effect sizes, for a large population it isn't. The thing that often happens in these sorts of situations is that the people who find it easy just say "look, it's easy" and think the people who find it hard will magically find it easy too.
This is why we need to think of ways to make heuristics as easy as possible based on the way people actually behave rather than trying to change the way they behave. If people work off vibes, then maybe think about the vibe that will be most effective. Tom Forth suggested electric things that get hot use a lot energy which is not a bad vibe to put out.
It would be good therefore if the government were to put out some simple heuristics so people would have a good grasp of effect sizes. But as my showbiz cousin pointed out, the government seemingly don't understand effect sizes themselves if it thinks £15 million is a huge amount of money to spend on an energy saving campaign (it is the equivalent of 0.0025% of the energy bills bail out).
So in short: if people make decision based on vibes rather than size, we need to find the vibes that reflect the size.
*When you point this out to people they say "Yes, but every little helps". It is quite difficult to change someone's mind on this. To them doing a bit of good is better than doing no good at all, which is true. But in reality, it is just cope to make themselves feel better about putting on the heating rather than wearing a sweater. People like to feel good about themselves and you are just pissing on their chips.
** I think the lack of attention to effect sizes is partly down to academia. We are so concerned with establish correlation and causation that we forget the most important thing to people is often effect size.
***I actually know someone who became a vegan for health reason and still smoked!