The Benchmarking package is generally working well for me but one of its functions, dea.plot.transform, produces results that look odd to me. Under Ubuntu 10.04 LTS, I am running R version 2.13.2 and Benchmarking version 0.20 ($Revision: 118 $). In that environment, I tried executing the following code: y1 = c(0, 2, 6, 8) y2 = c(7, 4, 5, 0) library(Benchmarking) dea.plot.transform(y1, y2) My expectation was that the code would produce a continuous, piecewise-linear transformation curve (production possibility frontier) passing through the points (0, 7), (6, 5), and (8, 0). Instead, it produced a horizontal line segment from (0, 7) to (6, 7) and a separate line segment from (6, 5) to (8, 0). The discontinuity appears to me to be a mistake. If anyone could help me understand why my code is not producing the expected transformation curve and how to correct the problem, I would be most grateful. Best regards, John -- John P. Burkett Department of Economics University of Rhode Island Kingston, RI 02881-0808 USA phone (401) 874-9195