Topics: Economics and Personal Finances, Socioeconomic Class. 1  Richard Fry is a senior researcher focusing on economics and education at Pew Research Center. 2  Rakesh Kochhar is an associate director of research at Pew Research Center.
In the United States, the Census Bureau determines who is poor using an economic poverty measure, by calculating official poverty estimates using a set of dollar-value thresholds, or minimum amount of income needed to meet basic needs, that vary by family size and composition.
Optimal behavior is defined as an action that maximizes the difference between the costs and benefits of that decision. Three primary variables are used in the optimality model: decisions, currency, and constraints. Decision involves evolutionary considerations of the costs and benefits of their actions.