The Bock and Aitkin Marginal Maximum Likelihood/EM (MML/EM) approach to item parameter estimation is an alternative to the classical joint maximum likelihood procedure of item response theory. This paper provides the essential mathematical details of a MML/EM solution and shows its use in obtaining consistent item parameter estimates. (TJH)

A reduction in agricultural activity in a rural farming community will result in reduced activity in almost every sector of the local economy. The result may be measured in loss of employment and income. This report provides a method to estimate such economic impacts with a minimum of data collection and manipulation. Most of the input data…