I didn’t get a lot out of Bayes at the first CFAR workshop, when the class involved mentally calculating odds ratios. It’s hard for me to abstractly move numbers around in my head. But the second workshop I volunteered at used a Bayes-in-everyday-life method where you drew (or visualized) a square, and drew a vertical line to divide it according to the base rates of X versus not-X, and then drew a horizontal line to divide each of the slices according to how likely you were to see evidence H in the world where X was true, and the world where not-X was true. Then you could basically see whether the evidence had a big impact on your belief, just by looking at the relative size of the various rectangles. I have a strong ability to visualize, so this is helpful.
I visualize this square with some frequency when I notice an empirical claim about thing X presented with evidence H. Other than that, I query myself “what’s the base rate of this?” a lot, or ask myself the question “is H actually more likely in the world where X is true versus false? Not really? Okay, it’s not strong evidence.”
I didn’t get a lot out of Bayes at the first CFAR workshop, when the class involved mentally calculating odds ratios. It’s hard for me to abstractly move numbers around in my head. But the second workshop I volunteered at used a Bayes-in-everyday-life method where you drew (or visualized) a square, and drew a vertical line to divide it according to the base rates of X versus not-X, and then drew a horizontal line to divide each of the slices according to how likely you were to see evidence H in the world where X was true, and the world where not-X was true. Then you could basically see whether the evidence had a big impact on your belief, just by looking at the relative size of the various rectangles. I have a strong ability to visualize, so this is helpful.
I visualize this square with some frequency when I notice an empirical claim about thing X presented with evidence H. Other than that, I query myself “what’s the base rate of this?” a lot, or ask myself the question “is H actually more likely in the world where X is true versus false? Not really? Okay, it’s not strong evidence.”