The key element in realizing low cost real{time software implementations of a H.263 videoconferencing system is a fast motion estimation algorithm, which only slightly decreases coding e ciency. We propose a spatio{temporal recursive estimator that combines an excellent coding e ciency with a high computational e ciency. Experimentally, the new algorithm proves to be comparable to full{search b...

This paper uses data on the world’s copper mining industry to measure the impact on e¢ ciency of the adoption of the ISO 14001 environmental standard. Anecdotal and case study literature suggests that …rms are motivated to adopt this standard so as to achieve greater e¢ ciency through changes in operating procedures and processes. Using plant level panel data from 19922007 on most of the world’...

I consider the problem of allocating N indivisible objects among N agents according to their preferences when transfers are absent and an outside option may exist. I study the tradeo between fairness and e ciency in the class of strategy-proof mechanisms. The main nding is that for strategy-proof mechanisms the following e ciency and fairness criteria are mutually incompatible: (1) ex-post e ci...

Th e electricity generating effi ciency is the energy in the net electricity generated divided by the energy in the fuel used to generate that electricity on an all-in basis. Higher effi ciency means less coal consumed and reduced emissions per unit of electricity. Th e chemical energy in the fuel can be expressed as either its Lower Heating Value (LHV) or its Higher Heating Value (HHV) [5]. In...

This paper discusses and reviews the use of super-eciency approach in data envelopment analysis (DEA) sensitivity analyses. It is shown that super-eciency score can be decomposed into two data perturbation components of a particular test frontier decision making unit (DMU) and the remaining DMUs. As a result, DEA sensitivity analysis can be done in (1) a general situation where data for a tes...

This paper is concerned with empirical and theoretical basis of the E¢ cient Market Hypothesis (EMH). The paper begins with an overview of the statistical properties of asset returns at di¤erent frequencies (daily, weekly and monthly), and considers the evidence on return predictability, risk aversion and market e¢ ciency. The paper then focuses on the theoretical foundation of the EMH, and sho...

In this note, we provide a multistage game form which may be used for managing aggressive ‡ows which may cause network congestion or monopolisation. The mechanism here presented attains economic e¢ciency, technical e¢ciency and other desirable properties.

We characterize the sharing rule for which a contribution mechanism achieves e¢ ciency in a cooperative production setting when agents are heterogeneous. The sharing rule bears no resemblance to those considered by the previous literature. We also show for a large class of sharing rules that if Nash equilibrium yields e¢ cient allocations, the production function displays constant returns to sc...

In Data Envelopment Analysis when the number of decision making units is small the number of units of the dominant or e cient set is relatively large and the average e ciency is generally high The high average e ciency is the result of assuming that the units in the e cient set are e cient If this assumption is not valid this results in an overestimation of the e ciencies which will be larger f...

The problem of labelling speaker turns by automatically segmenting and clustering a continuous audio stream is addressed. A new clustering scheme is presented and evaluated using a clustering e ciency score which treats both agglomerative and divisive clustering strategies equally. Results show an e ciency of 70% can be obtained on both manually and automatically derived segments on the 1996 Hu...