The theory of decision analyzes how people choose actions that lead to the best results given their preferences. There are different types of decisions, including those without risk between incommensurable goods, choices under unpredictability, and intertemporal choices about assigning value over time. Most decision theory is normative, identifying optimal decisions assuming rationality and complete information. However, human behavior often deviates from these predictions. The paradox of choice also observes that too many options can lead to poor decisions or paralysis.