scholarly journals Afriat and arbitrage

Author(s):  
Alan Beggs

AbstractThis paper presents a proof of Afriat’s (Int Econ Rev 8:67–77) theorem on revealed preference by using the idea that a rational consumer should not be vulnerable to arbitrage. The main mathematical tool is the separating hyperplane theorem.

2019 ◽  
Author(s):  
Chem Int

Recently, process control in wastewater treatment plants (WWTPs) is, mostly accomplished through examining the quality of the water effluent and adjusting the processes through the operator’s experience. This practice is inefficient, costly and slow in control response. A better control of WTPs can be achieved by developing a robust mathematical tool for performance prediction. Due to their high accuracy and quite promising application in the field of engineering, Artificial Neural Networks (ANNs) are attracting attention in the domain of WWTP predictive performance modeling. This work focuses on applying ANN with a feed-forward, back propagation learning paradigm to predict the effluent water quality of the Habesha brewery WTP. Data of influent and effluent water quality covering approximately an 11-month period (May 2016 to March 2017) were used to develop, calibrate and validate the models. The study proves that ANN can predict the effluent water quality parameters with a correlation coefficient (R) between the observed and predicted output values reaching up to 0.969. Model architecture of 3-21-3 for pH and TN, and 1-76-1 for COD were selected as optimum topologies for predicting the Habesha Brewery WTP performance. The linear correlation between predicted and target outputs for the optimal model architectures described above were 0.9201 and 0.9692, respectively.


2020 ◽  
Vol 26 (1) ◽  
pp. 23-34
Author(s):  
B. M. Grinchel’ ◽  
E. A. Nazarova

The presented study examines methods for analyzing and managing sustainable economic development of Russian regions and possible criteria for assessing and improving sustainability.Aim. The study aims to provide a theoretical and empirical justification for the use of regional competitive attractiveness assessment to manage economic development and improve its sustainability.Tasks. Based on the measurement and analysis of economic competitive attractiveness indicators and their mathematical treatment, the authors assess the sustainability of development of Russian regions in 2013–2017 and the causes of deviations from progressive growth.Methods. This study proposes a mathematical tool for measuring the sustainability of Russian regions by assessing their competitive attractiveness and develops a typology of sustainability in the mathematical space of two variables.Results. Methods for analyzing and managing the sustainability of economic development of Russian regions under the influence of political and economic challenges and risks are proposed. The level and dynamics of regional competitive attractiveness are taken as a criterion of sustainability of economic development. The authors provide methods and indicators for assessing economic competitive attractiveness and criteria for measuring the sustainability of development, which allow them to draw conclusions about the reaction of different regions to the challenges and risks of development in 2013–2017. The study proposes a management scheme for sustainable regional development with a focus on the comprehensive improvement of regional economic competitive attractiveness and potential ways to improve it, including training of municipal and regional managers in crisis management associated with economic and political challenges and risks.Conclusions. Based on the proposed criterion of economic development sustainability and assessment of the competitive attractiveness of regions and their rankings, it is shown that in 2013–2017 45 out of 83 regions were developing sustainably; by 2017, 19 regions out of the 32 that suffered losses in the competitive attractiveness level and rankings in 2015–2016 have managed to restore the sustainability of economic development and their rankings. This study proves that regions with a high level of economic competitive attractiveness show increased sustainability of development.


2013 ◽  
Author(s):  
Fabrice Nobibon Talla ◽  
L. Cherchye ◽  
Yves Crama ◽  
Thomas Demuynck ◽  
Bram De Rock ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document