I thought rational ignorance was a part of bounded rationality--people do not investigate every contingency because they do not have the computational power to do so, and thus their decision-making is bounded by their computational power.
You have distinguished this from motivated cognition, in which people succumb to confirmation bias, seeing only what they want to see. But isn't a bias just a heuristic, misapplied? And isn't a heuristic a device for coping with limited computational capacity? It seems that a bias is just a manifestation of bounded rationality, and that this includes confirmation bias and thus motivated cognition.
Yes, bounded-rationality and rational ignorance are consequnces of the limits of human computational power. But humans have more than enough computational power to do better than in-group bias, anchoring effects, deciding when to follow authority simply because it is authority, or believing something because we want it to be true.
We've had that capacity since the recorded history began, but ordinary people tend to not notice that they are not considering all the possibilities. By contrast, it's not uncommon for people to realize that they lack some relev...
I'm interested in how courts and juries might use rational techniques to arrive at correct decisions on guilt.
In a complex case, it would seem to sensible to assess each component of the prosecution and defence case, and estimate the relative likelihood. If the prosecution case is (say) 100 times more likely than the defence case, then you can say the defendant is guilty beyond reasonable doubt.
I never heard of this being done though. I recently made an analysis of the Massei report into the Amanda Knox case. It looked like this ( see http://massei-report-analysis.wikispaces.com/ for the entire analysis and some insight into the numbers below ).
This is perhaps a bit vague. It's not a great example, because in the end I didn't find any credible prosecution evidence. It's not entirely clear what the "probability" numbers here actually are, and whether two columns are needed. But hopefully it shows that the Massei's account of the murder is quite improbable, and there is considerable doubt.
I'm interested in possibly devising a more complete framework for how such an assessment should be done, the pitfalls that need to be guarded against (how uncertain are the probability estimates?), and even views as to how "reasonable doubt" should be quantified.
Perhaps readers would like to make an assessment of other interesting cases, to explore the issues.
Or how would you approach this problem?