An empirical procedure is suggested for testing a model that postulates variables that intervene between observed causes and observed effects against a model that includes no such postulate. The ...

Previous research has shown a fairly consistent relationship between religion and/ or religiosity and attitudes towards abortion. Data from a 1972 national sample is presented showing the importance ...

The intervention can be a one-time event. For example, you might want to study the effect of a short-term advertising campaign on the sales of a product. In this case, the input variable has the value ...