戦後アメリカに移住した日本人女性たちの動態 : American Community Survey 2011 PUMSデータの2次分析より

The objective of this paper is to estimate comprehensive environmental efficiency measures for Dutch dairy farms. The environmental efficiency scores are based on the nitrogen surplus, phosphate surplus and the total (direct and indirect) energy use of an unbalanced panel of dairy farms. We define environmental efficiency as the ratio of minimum feasible to observed use of multiple environmentally detrimental inputs, conditional on observed levels of output and the conventional inputs. We compare two methods for the calculation of efficiency; namely Stochastic Frontier Analysis (SFA) and Data Envelopment Analysis (DEA). This paper reveals the strengths and weaknesses for estimating environmental efficiency of the methods applied. Both SFA and DEA can estimate environmental efficiency scores. The mean technical efficiency scores (output-oriented, SFA 89%, DEA 78%) and the mean comprehensive environmental efficiency scores (SFA 80%, DEA 52%) differ between the two methods. SFA allows hypothesis testing, and the monotonicity hypothesis is rejected for the specification including phosphate surplus. DEA can calculate environmental efficiency scores for all specifications, because regularity is imposed in this method.

Environmental efficiency with multiple environmentally detrimental variables; estimated with SFA and DEA

Stock trading strategies play a critical role in investment. However, it is challenging to design a profitable strategy in a complex and dynamic stock market. In this paper, we propose an ensemble strategy that employs deep reinforcement schemes to learn a stock trading strategy by maximizing investment return. We train a deep reinforcement learning agent and obtain an ensemble trading strategy using three actor-critic based algorithms: Proximal Policy Optimization (PPO), Advantage Actor Critic (A2C), and Deep Deterministic Policy Gradient (DDPG). The ensemble strategy inherits and integrates the best features of the three algorithms, thereby robustly adjusting to different market situations. In order to avoid the large memory consumption in training networks with continuous action space, we employ a load-on-demand technique for processing very large data. We test our algorithms on the 30 Dow Jones stocks that have adequate liquidity. The performance of the trading agent with different reinforcement learning algorithms is evaluated and compared with both the Dow Jones Industrial Average index and the traditional min-variance portfolio allocation strategy. The proposed deep ensemble strategy is shown to outperform the three individual algorithms and two baselines in terms of the risk-adjusted return measured by the Sharpe ratio.

Deep Reinforcement Learning for Automated Stock Trading: An Ensemble Strategy

For over forty years, Business Tendency Surveys have been collected in multiple member states of the European Union. Previous research has studied the predictive accuracy of the expectation variables included in those surveys through bivariate, within-country, Granger-causality tests, which has resulted in mixed conclusions. We extend previous research in various ways, as we (i) explicitly allow for cross-country influences, and (ii) do so using both bivariate and multivariate Granger-causality tests. Specifically, the multivariate El-Himdi and Roy test is adapted to jointly test the forecasting value of multiple production expectation series, to assess whether part of this joint effect is indeed due to cross-country influences, and to determine which countries' expectation series have most "clout" in predicting the production levels in the other member countries, or have higher "receptivity", in that their production levels are Granger-caused by the other countries' expectations.

On The Predictive Content Of Production Surveys: A Pan-European Study

When combined, education and technology can build dynamic teaching and learning experiences that are tailored to developing and transforming the educators and learners needed to power the digital economy. For some reasons, however, there is still a big chunk of people especially students who aren’t ready yet to embrace the technological change in the field of education. This study aims to determine the factors affecting students’ e-learning technology acceptance particularly on Learning Management Systems (LMS) in the Filipino context. A conceptual model was proposed based on the Technology Acceptance Model (TAM) which was extended through the inclusion of Internet Connectivity Experience (ICE), Social Media Influence (SMI), Integrated Multimedia Instruction (IMI), System Interactivity (SI) and Perceived Quality Work of Life (PQWL) as additional predictor values. The constructs were determined according to the three-tier use model (3TUM) which was characterized to explore users’ attitudes towards IT at three levels. The target population in this research was Filipino students from colleges that are considered as promoters of elearning integration in the educational sphere in the Philippines. The collected data from 629 Filipino college students were analyzed using structural equation modeling (SEM) technique based on AMOS methods. Finally, a path model was created to examine the relationships between the factors to explain students’ adoption of e-learning technology from the information systems acceptance point of view. As a result, it provided practical and technical implications applicable for local and global school environments that could help educational leaders, educational technologists, educators and learners in their development, implementation, and acceptance of e-learning technology like LMS.

https://manuelgarcia.info/media/full_paper/elearning-philippines.pdf

E-Learning Technology Adoption in the Philippines: An Investigation of Factors Affecting Filipino College Students' Acceptance of Learning Management Systems

The aim of the presented article is to evaluate the impact of climate change on the sugar content of grapes in the Czech Republic during the period 2000–2019 through selected indicators on the basis of available secondary sources. Attention is focused on the developments in both the main wine-growing regions of Moravia and Bohemia. In the field of viticulture and wine-growing, the sugar content of grapes, as a basic parameter for the classification of wines, plays an important role. In the Czech Republic, the average sugar content of grapes has had a constantly growing trend. This trend is evident both in the wine-growing region of Bohemia and in the wine-growing region of Moravia. The impact of climate change, especially the gradual increase of average temperatures in the growing season, cannot be overlooked. It greatly affects, among other things, the sugar content of grapes. Calculations according to the Huglin Index and the Winkler Index were used to determine the relationship between climate and sugar content. These indexes summarize the course of temperatures during the entire vegetation period into a single numerical value. The results show that both indexes describe the effect of air temperature on sugar content in both wine regions of the Czech Republic in a statistically significant way. The Huglin Index shows a higher correlation rate. The Winkler Index proved to be less suitable for both areas. Alternatively, the Winkler Index calculated for a shorter growing season was tested, which showed a higher degree of correlation with sugar content, approaching the significance of the Huglin Index.

https://www.mdpi.com/2071-1050/13/1/222/pdf

The Impact of Climate Change on the Sugar Content of Grapes and the Sustainability of their Production in the Czech Republic

This paper is focused on evaluating the trading rule of indicator commodity channel index (CCI), using selected agricultural commodities. The reason of testing is that this indicator is calculated with respect to fluctuation of commodity market - volatility. The recent issue of commodity markets examines trading under risk. The concept is in analyzing of predictive power of CCI. The main core of this paper is if the trading strategy under evaluating using technical analysis, respectively CCI, reaches positive profit. The returns of trading rule are measured using signals to buying or selling and comparison each of them. Authors of this paper created trading rule based on CCI and tested it on commodity markets. The results are positive in term of % CCI. Findings of the strategy are positive due to measurement volatility involved in indicator. The commodity markets are volatile, time series are fluctuating due to actual announcements or news.

/pdf/commodity-channel-index-evaluation-of-trading-rule-of-ijsgzt4ub8.pdf

Commodity Channel Index: Evaluation of Trading Rule of Agricultural Commodities

This study provides background data and justification for the development of bio briquettes from palm oil empty fruit bunches (EFB) and evaluates a pilot project utilizing this palm oil industry waste by-product in Indonesia. This activity is also important from the environmental standpoint since it helps in achievement of sustainable environment in Indonesia. This is due to the fact that EFB that is left to decay and is not processed is a significant source of pollution (Chiew and Shimada, 2013). Indonesia has become the world’s biggest palm oil producer with more than 20 million tons crude palm oil (CPO). Annual growth rate is about of 10%. This helped to Indonesian economic growth and poverty alleviation, provided benefits for big companies and thousands of smallholders. But this led also to deforestation and reduction of biodiversity. The Indonesian palm oil industry now still did not recover from palm oil prices drop down and use of palm oil by products should be on the focus also to support this Indonesian main business. Palm oil is facing criticism for using food crop as fuels, but EFB is absolutely non-food palm oil production by product. This by-product is underestimated in economic way and relatively huge amount is not used in Indonesia and could potentially contribute to sustainable green energy production especially for power generation needs In Indonesia. (Mohammed et al., 2012) Keywords: Sustainable development, Crude Palm Oil, Briquettes, Renewable Energy, Profitability JEL Classifications: Q2; Q4, Q5

Economics of Palm Oil Empty Fruit Bunches Bio Briquettes in Indonesia

Each year, around 2% of the four million hectares of farmland in Czechia changes owners. However, after years of significant growth in prices, a slowdown in pace and demand is expected. Rising interest rates, a strengthening of the crown and legislative changes in 2018 have influenced the price of farmland. Yet the prices of farmland in Czechia are a third of those in the countries of Western Europe, and so it still represents an interesting opportunity for investors. Currently, land is bought primarily by the farmers who work it. In Czechia, 80% of farmers farm on hired land, and rent increases are starting to be an issue for many of them. The return on the investment in agricultural land is currently around 50 years for an owner and 25 years for a farmer working the land. As research has shown, the price of farmland is an important factor in the sustainable development of agriculture in Czechia, along with the greening of production and the fight against soil erosion and the effects of climate change.

The Price of Farmland as a Factor in the Sustainable Development of Czech Agriculture (A Case Study)

The aim of this article was to express social and economic aspects of the sustainable livestock production in relation to meat consumption in the Czech Republic and to predict the possibilities of further development of livestock production in the conditions of Czech agriculture. With the accession of Czechia to the EU (2004), the structure of Czech agriculture changed to the detriment of livestock production. The decisive sectors of livestock production are pig breeding, cattle breeding and poultry farming. This article (contribution) analyzes trends in the development of production in the basic categories of livestock, and it evaluates the degree of self-sufficiency of the economy in the given sector of agricultural production and the consumption of individual types of meat in Czechia. Using Holt’s model of statistical analysis, it then predicts the future consumption of meat and its individual types in the Czech Republic in the years 2020–2024. As research has shown, the sustainable development of livestock production and meat consumption in the Czech Republic depends not only on the mutual size of meat production and consumption or its quality, but also significantly on the market prices of meat (including world prices), as well as changes in eating habits of the population.

https://www.mdpi.com/2077-0472/11/2/102/pdf

Karel Šrédl

Papers

The Impact of Climate Change on the Sugar Content of Grapes and the Sustainability of their Production in the Czech Republic

Commodity Channel Index: Evaluation of Trading Rule of Agricultural Commodities

Economics of Palm Oil Empty Fruit Bunches Bio Briquettes in Indonesia

The Price of Farmland as a Factor in the Sustainable Development of Czech Agriculture (A Case Study)

Social and Economic Aspects of Sustainable Development of Livestock Production and Meat Consumption in the Czech Republic