Approximations and inference for envelopment estimators of production frontiers

Nonparametric methods have been commonly used to assess the performance of both private and public organizations. Among them, the most popular ones are envelopment estimators such as Free Disposal Hull (FDH) or Data Envelopment Analysis (DEA), which estimate the attainable sets and their efficient boundaries by enveloping the cloud of observed units in the appropriate input-output space. However, these nonparametric envelopment techniques do not provide estimates of marginal products and other coefficients of economic interest. This paper presents a new approach that provides local estimates of all the desired partial derivatives and economic coefficients, which complement and complete the analysis based on nonparametric envelopment estimators. We improve nonparametric estimators by estimating nonparametrically smoothed efficient boundaries and providing derivatives and other coefficients without having to assume any parametric structure for the frontier and the inefficiency distribution. Our approach offers several advantages, such as a flexible nonparametric adjustment of the efficient frontier based on local linear models; a general multivariate efficiency model based on directional distances where one can choose the desired benchmark direction; the possibility of assessing the impact of external-environmental variables; a bootstrap-based statistical inference for deriving confidence intervals on the estimated coefficients for nonparametric and robust frontier approximations; the possibility of including factors aggregating inputs or outputs and recovering the estimated coefficients in the original units. To demonstrate the usefulness of the proposed approach, we provide an illustration in the field of education, where economic coefficients are important but the parametric assumptions have been questioned

Do the home field, global advantage, and liability of unfamiliarness hypotheses hold? empirical evidence from Malaysia

The study explores the home field, global advantage, and liability of unfamiliarness hypotheses in the Malaysian banking sector. The results indicate that Malaysian banks have exhibited productivity progress mainly attributed to technological progress. The authors find negative relationship between foreign and government ownership and bank productivity. Likewise, the publicly listed banks have been relatively less productive compared to private banks, thus rejecting the market discipline hypothesis. The empirical findings suggest that foreign banks from the North American countries to be the least productive banking group lending support to the home field advantage and the limited form of the global advantage hypotheses

Measuring the efficiency of Serbian insurance companies

The transition period, and the still ongoing economic crisis, amplify the volatility in the domestic insurance market and forces the management of insurance companies to continuously monitor changes in the market, i.e. to identify risks and opportunities, and therefore to undertake certain activities. The focus of the business of insurance companies is based on satisfying the needs of existing and potential clients. Respecting the current situation in the insurance market in anticipation of future events, the management of insurance companies must create and implement the optimal strategy in line with the company’s capabilities. For this purpose it is necessary to measure the efficiency of the business, which is the subject of this paper where the Data Envelopment Analysis (DEA) method is applied to the case of insurance companies operating in Serbia

Effizienz und Wettbewerb im deutschen Bankensektor

In diesem Papier geben wir einen Überblick über den Wettbewerb und die Effizienz im deutschen Bankensektor. Wir nehmen dabei die Entwicklung in den letzten 15 Jahren in den Blick. Frühere Studien für Deutschland weisen darauf hin, dass das deutsche Bankensystem durch monopolistische Konkurrenz und durch moderat hohe Kosteneffizienz gekennzeichnet ist. Zudem scheinen Wettbewerb und Effizienz positiv miteinander verbunden. Des weiteren bestanden deutliche Unterschiede zwischen großen und kleinen Banken. Kleine Banken bevorzugten mehr das traditionelle Bankgeschäft, geringere Risiken und haben eher auf regional segmentierten Märk ten agiert. Die gegenwärtige Krise könnte zu tieferen Änderungen im Bankensystem führen, mit möglichen Folgen für Wettbewerb und Effizienz.In this paper we review the main findings on competition and efficiency for the German banking sector. Our aim is to give a bird view of the evolution during the past 15 years. Previous studies on Germany point to a banking system dominated by monopolistic competition and moderate cost efficiency. Competition and efficiency seem to be positively related. Furthermore significant differences existed between small and large banks. The business model of small banks was often more traditional, they preferred less risk and they acted on more segmented regional markets. The current crisis may lead to deep changes of the banking system, potentially with consequences for competition and efficiency

A cautionary note on methods of comparing programmatic efficiency between two or more groups of DMUs in data envelopment analysis

In some applications of data envelopment analysis (DEA) there may be doubt as to whether all the DMUs form a single group with a common efficiency distribution. The Mann-Whitney rank statistic has been used to evaluate if two groups of DMUs come from a common efficiency distribution under the assumption of them sharing a common frontier and to test if the two groups have a common frontier. These procedures have subsequently been extended using the Kruskal-Wallis rank statistic to consider more than two groups. This technical note identifies problems with the second of these applications of both the Mann-Whitney and Kruskal-Wallis rank statistics. It also considers possible alternative methods of testing if groups have a common frontier, and the difficulties of disaggregating managerial and programmatic efficiency within a non-parametric framework. © 2007 Springer Science+Business Media, LLC

Inefficiency in the German Mechanical Engineering Sector

This paper aims to examine the relative efficiency of German engineering firms using a sample of roughly 23,000 observations between 1995 and 2004. As these firms had been successful in the examination period in terms of output- and export-growth, it is expected that a majority of firms is operating quite efficiently and that the density of efficiency scores is skewed to the left. Moreover, as the German engineering industry is dominated by medium sized firms, the question arises whether these firms are the most efficient ones. Finally an increasing efficiency gap between size classes over time is important since that would be a signal for a structural problem within the industry. The analysis - using recently developed DEA methods like bootstrapping or outlier detection - contradicts the two first expectations. The firms proved to operate quite inefficiently with an overall mean of 0.69, and efficiency differs significantly with firm size whereas medium sized firms being on average the least efficient ones. When looking at changes in efficiency over time, we find a decreasing efficiency gap between size classes

Parent perceptions of their child’s and their own physical activity after treatment for childhood cancer

Purpose: Parents are important facilitators of physical activity for children, yet little is known about the perceptions of parents of childhood cancer survivors. We investigated parent perceptions of their own and their child’s physical activity levels after cancer treatment and examined associations with clinical, demographic, and psychosocial factors. Methods: We conducted a cross-sectional survey among 125 parents and 125 survivors. Parents reported on the perceived importance of their child being physically active and concerns regarding exercising after cancer treatment. Results: Parents and survivors self-reported median (range) of 127.5 (0–1260) and 220 (0–1470) min/week of moderate-to-vigorous physical activity. Most parents (n = 109, 98%) believed that physical activity was highly important for their child. Some parents (n = 19, 17%) reported concerns, most commonly regarding exercise safety (n = 7, 22%). Parents were more likely to perceive that their child should increase physical activity if their child was an adolescent and had high body fat percentage. Conclusions: Physical activity levels varied widely among survivors, reflecting factors including parents’ lifestyles, limited understanding of exercise benefits and perceptions of risk. Given survivors’ insufficient physical activity levels and sedentary behaviour among families, embedding physical activity promotion into health systems and follow-up support could benefit the entire family unit

The importance of the cellular stress response in the pathogenesis and treatment of type 2 diabetes

Organisms have evolved to survive rigorous environments and are not prepared to thrive in a world of caloric excess and sedentary behavior. A realization that physical exercise (or lack of it) plays a pivotal role in both the pathogenesis and therapy of type 2 diabetes mellitus (t2DM) has led to the provocative concept of therapeutic exercise mimetics. A decade ago, we attempted to simulate the beneficial effects of exercise by treating t2DM patients with 3 weeks of daily hyperthermia, induced by hot tub immersion. The short-term intervention had remarkable success, with a 1 % drop in HbA1, a trend toward weight loss, and improvement in diabetic neuropathic symptoms. An explanation for the beneficial effects of exercise and hyperthermia centers upon their ability to induce the cellular stress response (the heat shock response) and restore cellular homeostasis. Impaired stress response precedes major metabolic defects associated with t2DM and may be a near seminal event in the pathogenesis of the disease, tipping the balance from health into disease. Heat shock protein inducers share metabolic pathways associated with exercise with activation of AMPK, PGC1-a, and sirtuins. Diabetic therapies that induce the stress response, whether via heat, bioactive compounds, or genetic manipulation, improve or prevent all of the morbidities and comorbidities associated with the disease. The agents reduce insulin resistance, inflammatory cytokines, visceral adiposity, and body weight while increasing mitochondrial activity, normalizing membrane structure and lipid composition, and preserving organ function. Therapies restoring the stress response can re-tip the balance from disease into health and address the multifaceted defects associated with the disease