Does capital punishment work? I hate the idea of the death penalty - not because I think there’s a load of good evidence that it doesn’t really deter criminals, or because I know the exact number of people put to death who later turned out to be innocent. I haven’t actually really taken a proper look at the evidence at all. Honestly, my real reason for opposing the death penalty is that it
Really great example of how easy it is to shape the story you want. Another great example I saw recently was a paper on unaffordable housing. It claimed "Almost nowhere in the United States Can You Afford the Median Rent While Making Minimum Wage."
Of course not; you're comparing the lowest incomes with the middle of the road housing cost.
You can make statistics say pretty much anything you want, but it's not healthy for actually having a productive discussion.
In machine learning, it's very common to encounter over-fitting, where your model (analogous to a "simplified summary of the literature") works for the training data ("the literature I'm citing") but not in general ("the real world"). It's standard practice to train on e.g. 80% of your data and run that model against both the training data and the randomly withheld 20%. If it's worse on the 20%, it will probably be that bad in the real world.
It would be interesting to try something like that, acknowledging that there are far fewer "data points" to split out. But it would encourage humility (and /specificity/) in simplified summaries, especially once you realize that, unless you specify the boundaries of where your summary applies, your holdout set might randomly include the effect's attempted replication with baby Eskimos.
The studies you provide allows us to update a little in favor of the deterrence of capital punishment, but crime is so complex statistical analysis can only provide limited insight. Are the studies really controlling for all cofounding variables?
I think it would be better to look at criminal justice systems of different countries such as Singapore.
Singapore is an Island nation and you have to smuggle in drugs through boats or airplanes- though some people are trying use drones now. Before, you enter the country there is a stern warning, telling people to give their drugs to the flight/ship attendant or else you will get executed. Compared to other similar countries less drugs get smuggled into Singapore. I would think the threat of getting executed would be a reason why.