Ralf Wetzel attempts to establish a similar baseline, first, by showing that the target behavior, compulsive stealing, has been occurring with a substantial frequency for at least 5 years prior to the beginning of the study. Wisely, he supplements these indirect data with a period of direct, quantitative observation. Secondly, it is not clear why Wetzel did not take more energetic steps to explore the possible effects of eliminating some of the natural consequences that may have served to maintain Mike's stealing. Mike's case worker suspected that he was "buying affections". Another closely related question is whether Mike's treatment by the child care staff may not have changed as a result of their training in behavioral techniques and exposure to an illustration of their effectiveness. It is obvious that the child care workers were interested in the program, since several of them followed Mike into the kitchen when the visit with Maria was first denied.