Heteroscedasticity and non-monotonic efficiency effects of a stochastic frontier model

We consider a model that provides flexible parameterizations of the exogenous influences on inefficiency. In particular, we demonstrate the model's unique property of accommodating non-monotonic efficiency effect. With this non-monotonicity, production efficiency no longer increases or decreases monotonically with the exogenous influence; instead, the relationship can shifts within the sample. Our empirical example shows that variables can indeed have non-monotonic effects on efficiency. Furthermore, ignoring non-monotonicity is shown to yield an inferior estimation of the model, which sometimes results in opposite predictions concerning the data.stochastic frontiers; heteroscedasticity; non-monotonic effects

Symmetrical Information and Credit Rationing: Graphical Demonstrations

As this article shows, the pro-debtor U.S. Bankruptcy Code alone can cause credit rationing, even without asymmetrical information in the market, because the code entails substantial costs to lenders if borrowers file for bankruptcy. In the absence of bankruptcy cost, lenders are always justified in raising interest rates and clearing markets. If the bankruptcy cost is nontrivial, however, lenders' profits are concave in the relevant range of interest rates. Thus, lenders cannot always clear the market by using higher rates. The study reported here also found that the use of collateral in debt contracts can reduce rationing but that even 100 percent collateral does not eliminate all rationing possibilities. A positive relationship was found between credit risk and the amount of pledged collateral, which is not necessarily true with models based on asymmetrical information.Company Failures; Credit Control; Debt

One-step and two-step estimation of the effects of exogenous variables on technical efficiency levels

Consider a stochastic frontier model with one-sided inefficiency u, and suppose that the scale of u depends on some variables (firm characteristics) z. A one-step model specifies both the stochastic frontier and the way in which u depends on z, and can be estimated in a single step, for example by maximum likelihood. This is in contrast to a two-step procedure, where the first step is to estimate a standard stochastic frontier model, and the second step is to estimate the relationship between (estimated) u and z. In this paper we propose a class of one-step models based on the scaling property that u equals a function of z times a one-sided error u * whose distribution does not depend on z. We explain theoretically why two-step procedures are biased, and we present Monte Carlo evidence showing that the bias can be very severe. This evidence argues strongly for one-step models whenever one is interested in the effects of firm characteristics on efficiency levels.technical efficiency; stochastic frontiers

Estimating fixed-effect panel stochastic frontier models by model transformation

Traditional panel stochastic frontier models do not distinguish between unobserved individual heterogeneity and inefficiency. They thus force all time-invariant individual heterogeneity into the estimated inefficiency. Greene (2005) proposes a true fixed-effect stochastic frontier model which, in theory, may be biased by the incidental parameters problem. The problem usually cannot be dealt with by model transformations owing to the nonlinearity of the stochastic frontier model. In this paper, we propose a class of panel stochastic frontier models which create an exception. We show that first-difference and within-transformation can be analytically performed on this model to remove the fixed individual effects, and thus the estimator is immune to the incidental parameters problem. Consistency of the estimator is obtained by either N→∞ or T→∞, which is an attractive property for empirical researchersStochastic frontier models; Fixed effects; Panel data

Smart partition system – A room level support system for integrating smart technologies into existing buildings

AbstractWe proposed a support system called the “Smart Partition System” for infill elements that integrate smart technologies according to the Open Building principles. The design requirements were collected from design practitioners. These design requirements consisted of both architectural and information subsystems. The Smart Partition System was composed of the following multiple levels of smartness: the foundation/core level with an embedded design knowledge in the support system and the utility level with a modular infill that integrate smart technologies. We constructed functional prototypes to demonstrate the feasibility of our proposed support system and some of the possibilities of the smart infill elements. Furthermore, the prototypes were evaluated by design practitioners. We compared our approach with current practices of smart building developments, and we also discussed some future prospects

Stochastic frontier models

The stochastic frontier model was first proposed in the context of production function estimation to account for the effect of technical inefficiency. The inefficiency causes actual output to fall below the potential level (that is, the production frontier) and also raises production cost above the minimum level (that is, the cost frontier). Recent applications of the model are found in many fields of study including labour, finance, and economic growth. In these applications, the observed outcome (of wages, investment, and so on) is modelled as being deviating from a frontier level in one direction owing to factors such as information asymmetry

Heteroscedasticity and non-monotonic efficiency effects of a stochastic frontier model

We consider a model that provides flexible parameterizations of the exogenous influences on inefficiency. In particular, we demonstrate the model's unique property of accommodating non-monotonic efficiency effect. With this non-monotonicity, production efficiency no longer increases or decreases monotonically with the exogenous influence; instead, the relationship can shifts within the sample. Our empirical example shows that variables can indeed have non-monotonic effects on efficiency. Furthermore, ignoring non-monotonicity is shown to yield an inferior estimation of the model, which sometimes results in opposite predictions concerning the data

Symmetrical Information and Credit Rationing: Graphical Demonstrations

As this article shows, the pro-debtor U.S. Bankruptcy Code alone can cause credit rationing, even without asymmetrical information in the market, because the code entails substantial costs to lenders if borrowers file for bankruptcy. In the absence of bankruptcy cost, lenders are always justified in raising interest rates and clearing markets. If the bankruptcy cost is nontrivial, however, lenders' profits are concave in the relevant range of interest rates. Thus, lenders cannot always clear the market by using higher rates. The study reported here also found that the use of collateral in debt contracts can reduce rationing but that even 100 percent collateral does not eliminate all rationing possibilities. A positive relationship was found between credit risk and the amount of pledged collateral, which is not necessarily true with models based on asymmetrical information