The article discusses how people make decisions when they are unsure about probabilities. The researchers found that certain measures can help us understand this uncertainty, which they call perceived ambiguity. They show that changes in how much we fear ambiguity do not affect these measures. This helps us see that these measures only reflect our uncertainty about probabilities, not our fear of ambiguity. The researchers applied their findings to different models of decision-making under uncertainty to see how they compare in terms of ambiguity.