Marta Tienda sees life stories in numbers. She is a sociologist, a scientist who studies human society. Numbers are the tools she uses to uncover fascinating information about people and their behavior. As the daughter of an illegal Mexican immigrant, Marta Tienda understands the pain of growing up poor. When her family had to pick crops to earn money, Marta saw firsthand the tough conditions that migrant workers had to endure. It was an experience...