Association for Behavior Analysis International

In psychophysics and perception, sensitivity to differences in magnitude comes in two forms, discrimination and scaling. Animal behavioral methods show how animals scale various stimulus properties. Since there are procedures that work well with animals for obtaining scales, scaling cannot be mentalistic. Scales are important because they are useful in predicting behavior. Quantitative analysis of behavior is largely built around how animals respond relative to the rate of reinforcement, a stimulus property of reinforcement. The rate of responding is a way of scaling the perceived value of various reinforcement contingencies. Here, task difficulty may be viewed as another stimulus or contingency dimension. How difficult a discrimination is, has most often been found by varying the closeness of stimuli along some dimension. These are all flat forms of difficulty, meaning that, these are direct properties of the stimulus or the response. Here we are going to consider the order of hierarchical complexity of the task requirements, a property of the overall contingency, which is a different form of difficulty. We are also going to look separately at the dimension of the time between the reinforcer and the response. Finally, a model is presented that integrates the two. The models discussed here will be shown to have a number of applications.

The Model of Hierarchical Complexity is a quantitative behavioral-developmental theory that suggests an objective way of determining the a priori difficulty of a tasks contingencies. The model explains why stage-like performances are observed. The model proposes that stages result from the hierarchical structure of tasks. A task is defined as hierarchically more complex when it organizes, in a non-arbitrary fashion, two or more less complex tasks. Using this model, sixteen orders of hierarchical complexity have been generated. In this study, the model is used to generate stimuli in the form of either problems or stories. The stimuli within a domain consist of an ordered series of tasks, from order 1, reflexes and conditioned reflexes, up to order 12, the discrimination of efficient market. Tasks were generated in several domains, including reinforcement contingencies (economic), mathematical, scientific, moral, political, and social domains. 280 people were recruited through online groups. A Rasch analysis of the responses showed that, within each domain, items were well scaled on a single dimension reflecting the predicted difficulty of the item. Participants performances were shown to conform to the predictions of the model, with very high amounts of variance accounted for (from .73% and up).

Accounts of stage and moral action have not integrated behavioral, developmental and quantitative paradigms. This presentation integrates the three by using a mathematical model of value obtained from developmental action and from stage, as in the Model of Hierarchical Complexity. The result is a behavioral-developmental account of stage and action, rather than a mentalistic one. Both value and stage are necessary for determining actions. Each consists of a matrix. The Value matrix has a number of vectors. For humans, there are 6 Holland Code variables in the value vector. The second vector is discounting-difference ratio between change in the overall value vector and change in time. The third vector is the change in differences in value over time, or risk. The second matrix is Stage, which measures performance in meeting difficulties produced by the order of hierarchical complexity of particular tasks, as discussed in the earlier talks. A mathematical account of the value and the stage matrices and their interaction terms are used to predict moral behavior.