We are interested in subverting the notion of "type" when it comes to biblical characters. We prefer, instead, to see the characters in Ruth as complex people, not merely built around a single primary trait, like loyalty, altruism, or generosity.

People may exhibit conflicting traits and are often different people. There is no reason why the same should not be true of literary characters. Accordingly we have tried not to define the "selves" of this narrative too tightly, and if we have overdetermined them, we recognize that as a fault. In short, the characters of this story have far more diverse possibilities of life in the minds of readers than we can ever give them. --from the Introduction