F€are and Grosskopf (2004) address the approach of Seiford and Zhu (2002) where undesirable input and output measures are treated in data envelopment analysis (DEA). One key feature of Seiford and Zhu s (2002) approach is that the bad outputs are treated as outputs in DEA model but are reduced when DEA efficiency is evaluated. F€are and Grosskopf (2004) suggest an alternative approach in treati...

Dual weight restrictions are commonly suggested as a remedy to the problem of low discriminatory power and absurd marginal prices in conventional Data Envelopment Analysis (DEA) models. However, weight restriction models also suffer from potential problems of infeasibility, lack of exogenous determination and ambiguous interpretations. The Symmetric Weight Assignment Technique (SWAT) addresses ...

Data envelopment analysis (DEA) models have been used in formulating the Malmquist index to measure productivity change over time periods. In this article, we question the validity of this index in the presence of input/output slacks that appear in DEA models used. We demonstrate with an application to banking that Malmquist index loses its meaning whenever slacks are present. As a corrective m...

A parametric analysis is an analysis whose input and output are parametrized with a number of parameters which can be instantiated to abstract properties after analysis is completed. This paper proposes to use Cousot and Cousot’s Cardinal power domain to capture dependencies of analysis output on its input and obtain a parametric analysis by parametrizing a base analysis. We illustrate the meth...

We develop comparative results for ratio-based efficiency analysis (REA), based on the decision making units’ (DMUs’) relative efficiencies over sets of feasible weights that characterize preferences for input and output variables. Specifically, we determine (i) ranking intervals which indicate the best and worst efficiency rankings that a DMU can attain relative to other DMUs, (ii) dominance r...

In this paper we consider issues that may arise in the I/O workload characterization for Parallel Access Volumes. Limiting the characterization of I/O device service time to the mean and the standard deviation is sufficient to correctly predict the average I/O time in a realistic model of a single-exposure device. Things are less simple, however, when one considers devices with multiple paralle...

The input/output stability of an interconnected system composed of an ordinary differential equation and a damped string equation is studied. Issued from the literature on time-delay systems, an exact stability result is firstly derived using pole locations. Then, based on the Small-Gain theorem and on the Quadratic Separation framework, some robust stability criteria are provided. The latter f...

Managing music audio databases for practicing musicians presents new and interesting challenges. We describe a systematic investigation to provide useful capabilities to musicians both in rehearsal and when practicing alone. Our goal is to allow musicians to automatically record, organize, and retrieve rehearsal (and other) audio to facilitate review and practice (for example, playing along wit...