Relationship of Ecosystem Services in the Beijing–Tianjin–Hebei Region Based on the Production Possibility Frontier

The supply and demand of ecosystem services are affected by land use. Only a few studies have conducted in-depth quantitative analyses. This study adopted the Beijing–Tianjin–Hebei region as the research area. The CLUMondo model was adopted to infer the land-use pattern under protection, development, and natural scenarios in 2035. Moreover, the InVEST model was utilized to evaluate carbon sequestration, water yield, and soil conservation under multiple land-use patterns. The production possibility frontier was drawn to visualize the trade-off relationship further. The trade-off intensity index was calculated to quantify the magnitude of the trade-off. (1) Under the development scenario, the accelerated expansion of urbanized land will occupy a large amount of arable and forest land, which should be planned and controlled. (2) The trade-off and synergistic relationships could be transformed under the different land-use scenarios. (3) The production possibility frontier curve for each ecosystem service trade-off and the optimal value of the trade-off configuration were plotted for the different scenarios. The trade-off intensity of ecosystem services was also calculated. This study combined ecosystem services with land-use regulations and revealed the link between ecosystem services and regional land-use pattern change. The aim is to provide a reference for the synergistic progress of the ecological economy in the Beijing–Tianjin–Hebei region.

BIOGAS PRODUCTION POSSIBILITY FROM AQUACULTURE WASTE

The research explores the possibilities of biogas extraction from aquaculture waste. Samples of fish-farming pool sludge were taken from a fish farm, which is located in the Krāslava district, Kalnieši rural municipality. Prior to experimental fermentation and extraction of biogas, samples were analyzed in order to determine their moisture and organic matter content (OMC). For purpose of increasing OMC available for fermentation, sludge was mixed with crushed reeds. Biogas was obtained from the samples at various ratios of sludge and reed residues. During the experiments, 3.81 liters of biogas were obtained from a mixture of fish-farming pool sludge and crushed reed at reed mass 100 g. The results of experimental research indicate that aquaculture residues can be used to produce biogas.

DEA Efficiency Region for Variations of Inputs and Outputs

Finding efficiency regions (ERs) for extremely efficient decision-making units (DMUs) is one of the important issues from the managerial and economic viewpoints. An extremely efficient DMU will remain efficient if and only if after changing its inputs and/or its outputs this DMU stays within its ER. Thus, by applying the ER information, decision maker(s) of the evaluated extremely efficient DMU can precisely understand the values of input(s) increment and output(s) decrement of this DMU so that it remains efficient. Hence, in this study, we propose a data envelopment analysis (DEA) approach based on the defining hyperplanes of the production possibility set (PPS), which is capable of finding the ERs of the DMUs when their inputs increase and/or their outputs decrease. To demonstrate the applicability of the proposed approach, in the real world, a numerical example and an empirical application to the banking industry in the Czech Republic are provided.

Novel models for obtaining the closest weak and strong efficient projections in data envelopment analysis

Data Envelopment Analysis (DEA) is a nonparametric method for measuring the relative efficiency and performance of Decision Making Units (DMUs). Traditionally, there are two issues regarding the DEA simultaneously i.e., the identification of a reference point on the efficient boundary of the production possibility set (PPS) and the use of some measures of distance from the unit under assessment to the efficient frontier. Due to its importance, in this paper, two alternative target setting models were developed to allow for lowefficient DMUs find the easiest way to improve its efficiency and reach to the efficient boundary. One seeks the closest weak efficient projection and the other suggests the most appropriate direction towards the strong efficient frontier surface. Both of these models provides the closest projection in one stage. Finally, a proposed problem is empirically checked by using a recent data related to 30 European airports.

Equilibrium of Invisible Hand in the Family: the Gravitation between Men and Women in Marriage Markets

The proof of the Invisible hand describes the inner market mechanism, which leads the producer to the meeting point with the uninformed consumer, where the price and the meeting time provide the maximization of the output on the consumption-leisure production possibility frontier and unintentionally maximize the buyer’s consumption-leisure utility. This mechanism also works in marriage markets where the Invisible hand corrects the misleading information. The paper confirms G. S. Becker’s assumption that more beautiful, charming, and talented women tend to marry wealthier and more successful men but refutes his conclusion that such marriage maximizes the aggregate output. The high male productivity really attracts women because it produces a strong male gravitation field. But the marriage of a very productive man to a beautiful woman fails because it represents for a beautiful woman a corner solution. The man’s wealth, accumulated before the marriage, as well the bride price reinforces this disequilibrium. A dowry can also result in a disequilibrium because it gives time for a man to look for another partner. The paper argues that the quality of men is determined not by their productivity as such but by the trade-off between the productivity and their ability to provide household services on the family consumption-leisure production possibility frontier. The quality of women is determined by the trade-off between household activity and efforts to support her natural female attractiveness. The invisible hand equilibrium represents something close to the mating of unlikes but with some peculiarities. The woman’s ability to provide household services substitutes the man’s household activity but it complements his gender-related quality of productivity. A housewife raises the productivity of her husband; she increases his attractiveness and reinforces his gravitation field at the expense of her own attractiveness and her gravitation field but only this way she maximizes her consumption-leisure utility. Polygamy also represents the invisible hand equilibrium but in this case the equal distribution of wealth between wives is followed by unequal distribution of household activities when some wives spend less time in the kitchen but more leisure time with the husband because they are more attractive. In monogamy, the woman’s strong gravitation field produces the phenomenon of the ‘tragedy of a femme fatale’. Her alliance with a wealthy man comes to the corner solution; she needs more attention of her husband but with that she decreases his gravitational field, and he becomes less interesting to her. The loss of male attractiveness results in the short time horizon of the equilibrium determined by the invisible hand.