We define and model the research production at Embrapa, the major Brazilian institution responsable for applied agricultural research. The main theoretical framework is Data Envelopment Analysis - DEA. We explore the economic interpretation and the statistical properties of these models to compute confidence intervals for output oriented efficiency measurements, based on a parametric flexible model, defined by the truncated normal distribution. These results provide a better insight on the efficiency classification and allow comparison among the DMUs involved int ehe evaluation process taking into account inefficiency random variation