Performance analysis in the presence of bounded, discrete and flexible measures_

In conventional data envelopment analysis (DEA) models, the relative efficiency of decision making units (DMUs) is evaluated while all measures with certain input and/or output status are considered as continuous data without upper and/or lower bounds. However, there are occasions in real-world applications that the efficiency of firms must be assessed while bounded elements, discrete values, and flexible measures are present. For this purpose, the current study proposes DEA-based approaches to estimate the relative efficiency of DMUs where bounded factors, integer values, and flexible measures exist. To illustrate it, radial models based on two aspects, individual and aggregate, are introduced to measure the performance of entities and to handle the status of the flexible measure such that there are bounded components and discrete data. Applications of approaches proposed in the areas of quality management, highway maintenance patrols, and university performance measurement are given to clarify the issue and to show their practicability. It was found that the introduced procedure can determine practical projection points for bounded measures and integer values (from the individual DMU viewpoint) and can classify flexible measures along with evaluation of DMUs relative efficiency.

Component-based regularization of a multivariate GLM with a thematic partitioning of the explanatory variables

We address component-based regularization of a multivariate generalized linear model (GLM). A vector of random responses [Formula: see text] is assumed to depend, through a GLM, on a set [Formula: see text] of explanatory variables, as well as on a set [Formula: see text] of additional covariates. [Formula: see text] is partitioned into [Formula: see text] conceptually homogenous variable groups [Formula: see text], viewed as explanatory themes. Variables in each [Formula: see text] are assumed many and redundant. Thus, generalized linear regression demands dimension reduction and regularization with respect to each [Formula: see text]. By contrast, variables in [Formula: see text] are assumed few and selected so as to demand no regularization. Regularization is performed searching each [Formula: see text] for an appropriate number of orthogonal components that both contribute to model [Formula: see text] and capture relevant structural information in [Formula: see text]. To estimate a single-theme model, we first propose an enhanced version of Supervised Component Generalized Linear Regression (SCGLR), based on a flexible measure of structural relevance of components, and able to deal with mixed-type explanatory variables. Then, to estimate the multiple-theme model, we develop an algorithm encapsulating this enhanced SCGLR: THEME-SCGLR. The method is tested on simulated data and then applied to rainforest data in order to model the abundance of tree species.

Equity of Bikeway Distribution in Minneapolis, Minnesota

Governments and nonprofit organizations are investing in the bicycling infrastructure. However, the benefits of the bicycling infrastructure have not always been distributed equally among neighborhoods, and the equity of the distribution has been a major concern. This study used two measures, the Gini coefficient and the loss of accessibility to jobs via bikeways, to assess both the horizontal and the vertical equity of the bicycling infrastructure's distribution in Minneapolis, Minnesota. Gini coefficients, calculated from Lorenz curves, provide a single flexible measure that allows comparisons within and between groups. Determination of accessibility to jobs via lower-stress bikeway and street networks allows the levels of connectivity via bikeways to be compared for different groups. Minneapolis is making substantial investments in the bicycling infrastructure and was used as a case study because data with which to assess changes in equity over time are available. With use of the block group as the unit of analysis, systemwide analyses of the distribution of bikeways relative to the locations of the population and total employment revealed increases in equity from 2010 to 2014. Comparison of Gini coefficients for all bicycling facilities among different subpopulations demonstrated horizontal inequities within each subgroup as well as indicators of vertical equity for various disadvantaged subgroups. The Gini coefficients revealed inequities in the distribution of urban trails for disadvantaged subpopulations. With the use of 3-mi network buffers, a bikeway penalty, calculated as the loss of job accessibility resulting from the choice to rely on a bikeway rather than on street networks, demonstrated a vertical equity for disadvantaged subgroups. These measures can be used to inform planning for and investments in bicycling facilities and to assess and compare the bicycling infrastructures of cities.

Mitigating impacts of water shortage on Egyptian agriculture: a catchment scale analysis

The impacts of water shortages on Egypt's agriculture continues to receive widespread attention. Several mitigation schemes have been proposed to reduce the potential economic impact of supply reductions of the Nile's waters into Egypt. This paper examines the economic consequences for the Egyptian agricultural economy of application of limited water markets to mitigate the impacts of potential water supply shortages. We address this aim by assembling detailed data on farm budgets, hydrology, institutions and culture in order to develop an integrated catchment framework for analyzing Egypt's use of the Nile. The results of our policy analysis illustrate that a limited form of water trading is one institutionally flexible measure that can mitigate the impacts of water shortages. When water supplies flowing into Egypt are reduced by 10 and 20% per year, adopting limited water trading reduces national farm income losses by 32 and 33% per year, respectively, compared to income losses borne without trading. So water trading grows in importance as a measure to sustain farm income in the face of more severe water shortages. Our findings provide insight for Egyptian policymakers to enable examination of options to mitigate the economic impacts of water supply shortages resulting from drought, climate change, or renegotiated arrangements for sharing the Nile's waters.