Using system dynamics modeling to understand the impact of social change initiatives

Community psychologists have a long history of interest in understanding social systems and how to bring about enduring positive change in these systems. However, the methods that community psychologists use to anticipate and evaluate the changes that result from system change efforts are less well developed. In the current paper, we introduce readers to system dynamics modeling, an action research approach to studying complex systems and the consequences of system change. We illustrate this approach by describing a system dynamics model of educational reform. We provide readers with an introduction to system dynamics modeling, as well as describe the strengths and limitations of the approach for application to community psychology.     

Recovery of Sensitivity to Prick and Touch after Pressure Block,with a Note on the Sensitivity of Hair Spots

In cloze tasks subjects are asked to supply words for deletions that occur in prose passages. In the present paper this task is related to more general word production tasks. Specifically, one aspect of decisions among several possible response alternatives was studied: the level of awareness of subjects producing competing responses. Two studies were done, differing only in the difficulty of the prose passages used as cloze tasks. In both studies, subjects (college students, n = 25) were asked to press a key hooked up to an event-graph for every option considered by them as a potential response. The main finding of the studies is that even in cases where the probability of a correct response is very low the distribution of responses considered deliberately is very small; on the average less than 1.5 words. The consequences of the finding for a theory of cloze in terms of a search and retrieval paradigm are discussed.