Estimation of a panel stochastic frontier model with unobserved common shocks

This paper develops panel stochastic frontier models with unobserved common correlated effects. The common correlated effects provide a way of modeling cross-sectional dependence and represent heterogeneous impacts on individuals resulting from unobserved common shocks. Traditional panel stochastic frontier models do not distinguish between common correlated effects and technical inefficiency. In this paper, we propose a modified maximum likelihood estimator (MLE) that does not require estimating unobserved common correlated effects. We show that the proposed method can control the common correlated effects and obtain consistent estimates of parameters and technical efficiency for the panel stochastic frontier model. Our Monte Carlo simulations show that the modified MLE has satisfactory finite sample properties under a significant degree of cross-sectional dependence for relatively small T. The proposed method is also illustrated in applications based on a cross country comparison of the efficiency of banking industries

Estimation of a Panel Stochastic Frontier Model with Unobserved Common Shocks

This paper proposes a panel stochastic frontier model with unobserved common shocks to control cross-sectional dependence among individual firms. The novel feature is that we separate technical inefficiency (decision-dependent heterogeneity) from the effects induced by individual heterogeneity (decision-independent) caused by unobserved common shocks. We propose a feasible maximum likelihood method that does not require estimating the effects of unobserved common shocks and discuss its asymptotic properties. Monte Carlo simulations show that the proposed method has satisfactory finite sample properties when cross-sectional dependence exists. Application is illustrated by comparison of the efficiency of savings and commercial banking industries in the US

Estimation of a Panel Stochastic Frontier Model with Unobserved Common Shocks

This paper proposes a panel stochastic frontier model with unobserved common shocks to control cross-sectional dependence among individual firms. The novel feature is that we separate technical inefficiency (decision-dependent heterogeneity) from the effects induced by individual heterogeneity (decision-independent) caused by unobserved common shocks. We propose a feasible maximum likelihood method that does not require estimating the effects of unobserved common shocks and discuss its asymptotic properties. Monte Carlo simulations show that the proposed method has satisfactory finite sample properties when cross-sectional dependence exists. Application is illustrated by comparison of the efficiency of savings and commercial banking industries in the US

Octopamine Neuromodulatory Effects on a Social Behavior Decision-Making Network in Drosophila Males

Situations requiring rapid decision-making in response to dynamic environmental demands occur repeatedly in natural environments. Neuromodulation can offer important flexibility to the output of neural networks in coping with changing conditions, but the contribution of individual neuromodulatory neurons in social behavior networks remains relatively unknown. Here we manipulate the Drosophila octopaminergic system and assay changes in adult male decision-making in courtship and aggression paradigms. When the functional state of OA neural circuits is enhanced, males exhibit elevated courtship behavior towards other males in both behavioral contexts. Eliminating the expression of the male form of the neural sex determination factor, Fruitless (FruM), in three OA suboesophageal ganglia (SOG) neurons also leads to increased male-male courtship behavior in these same contexts. We analyzed the fine anatomical structure through confocal examination of labeled single neurons to determine the arborization patterns of each of the three FruM-positive OA SOG neurons. These neurons send processes that display mirror symmetric, widely distributed arbors of endings within brain regions including the ventrolateral protocerebra, the SOG and the peri-esophageal complex. The results suggest that a small subset of OA neurons have the potential to provide male selective modulation of behavior at a single neuron level

Design and Fabrication of a Novel Micro Electromagnetic Actuator

The present study presents a new micro electromagnetic actuator utilizing a PDMS membrane with a magnet. The actuator is integrated with micro coils to electromagnetically actuate the membrane and results in a large deflection. The micro electromagnetic actuator proposed in this study is easily fabricated and is readily integrated with existing bio-medical chips due to its planar structure

Adaptive Momentum-Based Motion Detection Approach and Its Application on Handoff in Wireless Networks

Positioning and tracking technologies can detect the location and the movement of mobile nodes (MNs), such as cellular phone, vehicular and mobile sensor, to predict potential handoffs. However, most motion detection mechanisms require additional hardware (e.g., GPS and directed antenna), costs (e.g., power consumption and monetary cost) and supply systems (e.g., network fingerprint server). This paper proposes a Momentum of Received Signal Strength (MRSS) based motion detection method and its application on handoff. MRSS uses the exponentially weighted moving average filter with multiple moving average window size to analyze the received radio signal. With MRSS, an MN can predict its motion state and make a handoff trigger at the right time without any assistance from positioning systems. Moreover, a novel motion state dependent MRSS scheme called Dynamic MRSS (DMRSS) algorithm is proposed to adjust the motion detection sensitivity. In our simulation, the MRSS- and DMRSS-based handoff algorithms can reduce the number of unnecessary handoffs up to 44% and save battery power up to 75%

The Development of Spatial Attention U-Net for The Recovery of Ionospheric Measurements and The Extraction of Ionospheric Parameters

We train a deep learning artificial neural network model, Spatial Attention U-Net to recover useful ionospheric signals from noisy ionogram data measured by Hualien's Vertical Incidence Pulsed Ionospheric Radar. Our results show that the model can well identify F2 layer ordinary and extraordinary modes (F2o, F2x) and the combined signals of the E layer (ordinary and extraordinary modes and sporadic Es). The model is also capable of identifying some signals that were not labeled. The performance of the model can be significantly degraded by insufficient number of samples in the data set. From the recovered signals, we determine the critical frequencies of F2o and F2x and the intersection frequency between the two signals. The difference between the two critical frequencies is peaking at 0.63 MHz, with the uncertainty being 0.18 MHz.Comment: 17 pages, 7 figures, 3 table

Localized tail state distribution and hopping transport in ultrathin zinc-tin-oxide thin film transistor

Carrier transport properties of solution processed ultra thin (4 nm) zinc-tin oxide (ZTO) thin film transistor are investigated based on its transfer characteristics measured at the temperature ranging from 310K to 77K. As temperature decreases, the transfer curves show a parellel shift toward more postive voltages. The conduction mechanism of ultra-thin ZTO film and its connection to the density of band tail states have been substantiated by two approaches, including fitting logarithm drain current (log ID) to T-1/3 at 310K to 77K according to the two-dimensional Mott variable range hopping theory and the extraction of density of localized tail states through the energy distribution of trapped carrier density. The linear dependency of log ID vs. T-1/3 indicates that the dominant carrier transport mechanism in ZTO is the variable range hopping. The extracted value of density of tail states at the conduction band minimum is 4.75 x 10(20) cm(-3) eV(-1) through the energy distribution of trapped carrier density. The high density of localized tail states in the ultra thin ZTO film is the key factor leading to the room-temperature hopping transport of carriers among localized tail states. Published by AIP Publishing