Cost Inefficiency in the English and Welsh Water Industry: An Heteroskedastic Stochastic Cost Frontier Approach.

In this study we analyze the evolution of operating cost inefficiency for the English and Welsh water industry over the period 1995-2001 by estimating an heteroskedastic stochastic variable cost frontier. The main aim of this paper is to provide an overall picture of the industry cost inefficiency, as we consider both the water and sewerage companies and the smaller water only companies. The main results of this paper are that industry operating cost inefficiency has decreased over the sample period and that inefficiency differentials among firms have steadily narrowed. This pattern of inefficiency might have been generated by the incentives provided by comparative and capital market competition which became fully operative after the 1994 price review.

An Assessment on the Cost Structure of the UK Airport Industry: Ownership Outcomes and Long Run Cost Economies

In this paper we analyze the cost structure of the UK airport industry by estimating a variable cost function for the period 1994-2005. Overall results suggest that the long run average costs curve is U-shaped: it decreases until passenger traffic reaches approximately five millions, it remains flat over the range between five and fourteen million passengers and afterwards it starts to increase. Moreover, our findings provide evidence consistent with the existence of some degree of overcapitalization for the largest regulated airports. Finally, we analyze whether different forms of ownership entail cost differentials across airports and we find that privately owned airports are characterized by lower costs with respect to public and mixed ones, although cost differentials shrank over time as public and mixed airports improved their rate of cost reduction. Main results are robust to unobserved heterogeneity at the airport or market level and to possible endogeneity biases. Possible regulatory and policy implications of these results are also discussed.scale economies, public ownership, airports

On the Cahn-Hilliard-Brinkman system

We consider a diffuse interface model for phase separation of an isothermal incompressible binary fluid in a Brinkman porous medium. The coupled system consists of a convective Cahn-Hilliard equation for the phase field $\phi$, i.e., the difference of the (relative) concentrations of the two phases, coupled with a modified Darcy equation proposed by H.C. Brinkman in 1947 for the fluid velocity $\mathbf{u}$. This equation incorporates a diffuse interface surface force proportional to $\phi \nabla \mu$, where $\mu$ is the so-called chemical potential. We analyze the well-posedness of the resulting Cahn-Hilliard-Brinkman (CHB) system for $(\phi,\mathbf{u})$. Then we establish the existence of a global attractor and the convergence of a given (weak) solution to a single equilibrium via {\L}ojasiewicz-Simon inequality. Furthermore, we study the behavior of the solutions as the viscosity goes to zero, that is, when the CHB system approaches the Cahn-Hilliard-Hele-Shaw (CHHS) system. We first prove the existence of a weak solution to the CHHS system as limit of CHB solutions. Then, in dimension two, we estimate the difference of the solutions to CHB and CHHS systems in terms of the viscosity constant appearing in CHB

And Yet they Co-Move! Public Capital and Productivity in OECD: A Panel Cointegration Analysis with Cross-Section Dependence

In this paper we add to the debate on the public capital - productivity link by exploiting very recent developments in the panel time series literature that take into account cross sectional correlation in non-stationary panels. In particular we evaluate the productive effect of public capital by estimating various production functions for a panel of 21 OECD countries over the period 1975-2002. We find strong evidence of common factors that drive the cointegration relationship among variables; moreover, our results suggest a public capital elasticity of GDP in the range 0.05-0.15, depending on model specification. Results are robust to the evidence of spillovers from public capital investments in other countries and to controlling for other productivity determinants like human capital, the stock of patents and R&D capital.Public capital; Productivity; Panel Cointegration; Cross-section Dependence.

A Multi-Precision Bit-Serial Hardware Accelerator IP for Deep Learning Enabled Internet-of-Things

Deep Neural Networks (DNNs) computation-hungry algorithms demand hardware platforms capable of meeting rigid power and timing requirements. We introduce the Serial-MAC-engine (SMAC-engine), a fully-digital hardware accelerator for inference of quantized DNNs suitable for integration in a heterogeneous System-on-Chip (SoC). The accelerator is completely embedded in the form of a Hardware Processing Engine (HWPE) in the PULPissimo platform, a RISCV-based programmable architecture that targets the computational requirements of IoT applications. The SMAC-engine supports configurable precision for both weights (8/6/4 bits) and activations (8/4 bits), with scalable performance. Results in 65 nm technology demonstrate that the serial-MAC approach enables the accelerator to achieve a maximum throughput of 14.28 GMAC/s, consuming 0.58 pJ/MAC @ 1.0 V when operating at a precision of 4 bits for weights and 8 bits for activations

Human capital, employment protection and growth in Europe

Using data for 51 manufacturing and service sector for the period 1970-2005 in 14 countries, this paper show that employment protection legislation has a negative and significant effect on growth of value added and hours of work in more human capital intensive sectors. We argue that labour market regulation has a negative impact on the technology adoption mechanism through its heterogeneous impact on firms' workforce adjustment requirements. In fact, technology adoption depends both on the skill level of the workforce and the capacity of firms to optimally adjust their employment levels as technology changes. As a consequence, firing costs have a relatively stronger impact in sectors in which technology adoption is more important. Our empirical results are robust to various sensitivity checks such as interactions of human capital intensity with other country level variables, of employment protection with other sector level variables and endogeneity of firing restrictions. We also show that the negative effect of EPL is stronger the smaller the distance from the technology frontier and after the 1990s

Cost Inefficiency in the English and Welsh Water Industry: An Heteroskedastic Stochastic Cost Frontier Approach.

In this study we analyze the evolution of operating cost inefficiency for the English and Welsh water industry over the period 1995-2001 by estimating an heteroskedastic stochastic variable cost frontier. The main aim of this paper is to provide an overall picture of the industry cost inefficiency, as we consider both the water and sewerage companies and the smaller water only companies. The main results of this paper are that industry operating cost inefficiency has decreased over the sample period and that inefficiency differentials among firms have steadily narrowed. This pattern of inefficiency might have been generated by the incentives provided by comparative and capital market competition which became fully operative after the 1994 price review

The Appropriateness of the Poolability Assumption for Multiproduct Technologies: Evidence from the English Water and Sewerage Utilities

The empirical literature on the cost structure of multiproduct firms (e.g., public utilities providing in combination gas, water, and electricity) traditionally assumes a common technology across different products and stages of production, letting the issue of poolability unexplored. The appropriateness of this assumption is tested here by estimating a General cost function for samples of UK specialized and sewerage-diversified water utilities. The results show the existence of both aggregate scale economies and diseconomies of scope; more interestingly, the hypothesis that the two groups of water companies share the same technological parameters is rejected. Given the implications of this finding in terms of optimal industry configuration and possible restructuring policies (e.g., mergers and/or divestitures), our test suggests caution in pooling samples when undertaking empirical studies on data which refer to multiproduct technologies.Multiproduct technologies; Water and sewerage utilities; Poolability; General cost function

Human Capital, Employment Protection and Growth in Europe

Using data for a large sample of manufacturing and service sectors in 14 EU countries, this paper shows that the value added and TFP growth rate differential between high and low human capital intensive industries is greater in countries with low than countries with high levels of employment protection legislation. We also find that such negative effect of EPL is slightly stronger for countries near the technology frontier, in the manufacturing sector and after the 1990s. We interpret these results suggesting that technology adoption depends on the skill level of the workforce and on the capacity of firms to adjust employment as technology changes: therefore, firing costs have a stronger impact in sectors where technical change is more skill-biased and technology adoption more important

A folded Fabry-Perot cavity for optical sensing in gravitational wave detectors

Abstract The sensitivity of standard optical schemes for the readout of weak vibrations is limited thermal and radiation pressure fluctuations induced by the small interrogation area. We propose and analyze an optical configuration allowing to overcome this problem and optimize the sensitivity of the new generation of massive gravitational wave detectors