Dynamic and Stochastic Structures of U.S. Cotton Exports and Mill Demand

This study employs a structural time-series method to model and estimate U.S. cotton exports and mill use. The results show that the stochastic process governing cotton export fluctuations is transitory, while the process pertaining to mill use has transitory, seasonal, and secular origins. The estimated structural relationships after accounting for the unobserved components indicate U.S. cotton exports respond directly to higher international price relative to domestic price of cotton, while mill use responds directly to U.S. textile output price and cotton-to-polyester price ratio. Exchange rate volatility and the U.S. Export Enhancement Program have no significant effect on cotton exports.cotton exports, cotton mill use, Kalman filter, state space, unobserved components, Crop Production/Industries, International Relations/Trade, Production Economics, Productivity Analysis,

Institutional Forms of Philanthropy in West Africa

How do African foundations mobilize monetary and non monetary resources (methods, strategies)? Who contributes to their budget (individuals, organizations, businesses, members, boards) and to which extent (percentage of local resources versus foreign ones)? What limitations and obstacles do African foundations face in their resources mobilization policies and practices (lack of information, lack of strategic planning, and lack of skills)? Are they financially sustainable? To address those questions, we conduct a comparative analysis of five (5) foundations evolving in West Africa

Dynamics of Price-Cost Margins in the U.S. Meat Industry

This study analyses the stochastic behavior of price-cost margins (PCMs) in the U.S. meat industry. It, first, develops and estimates a vertical relationship economic model to derive PCMs in the U.S. meat industry (Beef, Pork, and Poultry). Second it analyzes the behavior of PCMs by decomposing them into their seasonal, cyclical, and trend components using the state-space and the Kalman filtering methods. Price-cost margins in the U.S. meat industry are governed by two common trends and two common cycles. The study also found cyclical variability of PCMs is the highest with chicken, secular variability of PCMs is the highest with pork, while seasonal variability of PCMs is the highest with beef.Price-cost margins, market channel, meat industry, state-space Kalman filter, Demand and Price Analysis, Livestock Production/Industries,

Le marka dans l'ensemble dialectal mandingue

La langue mandingue est un vaste continuum linguistique recouvrant une zone de l'Afrique Occidentale qui s’étend de l’embouchure de la Gambie à l’Ouest à la frontière occidentale du Ghana à l’Est. Si actuellement on dispose de nombreux travaux sur le bambara, le dioula et le mandinka qui ont permis de mieux connaître le mandingue, il n’en est pas de même en ce qui concerne cette autre variété du mandingue: le marka du Burkina Faso pour lequel des études linguistiques sont pour l’instant rarissimes. L’essentiel des travaux qui lui sont consacrés sont présentés dans la bibliographie. Notre objectif ici est de mettre en évidence quelques traits spécifiques au marka par rapport à d’autres dialectes mandingues sur le plan phonique, tonologique et grammatical. Sur le plan grammatical nous présenterons quelques faits qui rapprochent le marka et le mandinkan de Gambie. Mais avant d’y arriver nous allons procéder à une présentation du marka

Forecasting Agricultural Commodity Prices with Asymmetric-Error GARCH Models

The performance of a proposed asymmetric-error GARCH model is evaluated in comparison to the normal-error- and Student-t-GARCH models through three applications involving forecasts of U.S. soybean, sorghum, and wheat prices. The applications illustrate the relative advantages of the proposed model specification when the error term is asymmetrically distributed, and provide improved probabilistic forecasts for the prices of these commodities.GARCH, nonnormality, skewness, time-series forecasting, U.S. commodity prices, Demand and Price Analysis,

The Relationship Between Family Environment, Parenting Styles and Adolescents’ Well-Being in Cameroon

The main objective of this thesis was to explore the relationship between family environment, parenting styles and adolescents’ well-being in a sample of Cameroonian adolescents. A number of factors in adolescents’ home environment are believed to influence adolescents’ well-being. A theoretical framework of the relationship between the predictor variables of family environment, parenting styles and the moderator variables of family socio-economic status (parents’ education, parents’ occupation, family income and the type of family structure) and adolescents’ sex, age, with the criterion variable of well-being (measured in terms of adolescents’ self-esteem, level of functioning and academic achievement) was constructed. Three hundred and thirty eight (338) adolescents aged between 12 to 19 years from three bilingual schools in the Adamaoua and Centre provinces in Cameroon were included in the sample. Of these respondents, (56.8%) and (43.2%) were males and females respectively. Data were collected by means of a questionnaire battery. The Family Environment Scale (FES) was used as a measure of family environmental dimensions; Buri’s Parental Authority Questionnaire (PAQ) was used as a measure of parenting styles. In addition, the General Health Questionnaire (GHQ 12), the Hare Self-esteem Scale (HSES) and school grades were used as measures of adolescents’ well-being. Data analysis uncovered three parenting styles as perceived by the adolescents using z-scores. The findings reveal no age and sex differences on measures of well-being. Majority of the adolescents (41.1%) reported having authoritative parents followed by authoritarian parents (34.6%) and only (24.3%) of the respondents viewed their parents as permissive. The results of the factor analysis revealed family environmental dimensions similar to those described by Moos and Moos. These dimensions were labelled as factor 1: supportive dimension, factor 2: growth dimension and factor 3: organized dimension. Correlations between perceived family environmental factors, parenting styles and adolescents’ well-being were investigated. The results indicated positive correlation between permissive and authoritarian parenting styles with FES conflict (r=.11) and intellectual-orientation (r=.10) subscales respectively. Authoritative parenting style did not correlate with any dimension of the family environment despite being the main style used by parents as perceived by the adolescents. Authoritarian parenting style positively correlated with adolescents’ school self-esteem (r=.14) and general level of functioning(r=.14). Permissive parenting correlated with the three domains of adolescents’ self-esteem: home(r=.20), school(r=.21) and peer(r=.22) and their general level of functioning(r=.17). General functioning correlated with measures of self-esteem. There was negative correlation between authoritarian and authoritative parenting styles (r= -.20, p.05, level of functioning, R2 = .22, F (3, 334) = 2.47, p<0.5 and academic achievement, R2 = .029, F (3, 334) = 4.305, p<.005. Finally the FES organized dimension did not predict adolescents’ well-being. As for the parenting styles, the regression model which included parenting styles predicted peer self-esteem, R2 = .048, F (3, 334) = 5.65, p<.001, home self-esteem, R2 = .040, F (3, 334) = 4.58, p<.005, school self-esteem, R2 = .052, F (3, 334) = 6.15, p<.0005 and level of functioning, R2 = .045, F (3, 334) = 5.25, p<.001. The regression model did not show the effects of parenting styles on academic achievement. Moderator regression analyses were performed to test the moderating effects of family socioeconomic status and adolescents’ sex, age on the relation between family environment, parenting styles and adolescents’ well-being. The interactions of these moderator variables with FES supportive, growth, and organized dimensions and authoritative, authoritarian and permissive parenting styles were partially significant. Two sub scales of FES factor 2 with income were significant for adolescents’ level of functioning but not for the other two measures of well-being. Moderator regression of family income with FES factors 1 and 3 was not significant for adolescents’ well-being. Family income moderated the relation between authoritative and adolescents’ peer self-esteem. Authoritarian (β =.50) and permissive (β =-.63) parenting styles were the best predictors of adolescents’ academic achievement as compared to authoritative and their interactions with family income were statistically significant; authoritarian t(338) = 2.35, p<0.05, permissive t(338) = -2.22, p< 0.05. Parents’ education and occupation partially moderated the relation between the predicted variables and outcome variables. The interactions between the type of family structure and parenting styles and their relation with adolescents’ well-being were not statistically significant. As for adolescents’ sex and age, their interactions with FES (growth, supportive, organized) were not significant. Sex however, did not fully moderate the relation between parenting styles and adolescents’ well-being. Overall, the study has shown the validity of the ecological perspective in that certain factors contribute to adolescents’ well-being in Cameroon and the moderating effects of certain family SES on the relationship between family environment, parenting styles and adolescents’ well-being. Future studies should include both parents and adolescents’ views in assessing the social climate of the environment, parenting styles with a more rigorous hypotheses testing

Demand for livestock products in developing countries with a focus on quality and safety attributes: Evidence from case studies

The case studies and the synthesis papers were presented at a mini-symposium at the International Association of Agricultural Economists conference held in Beijing, Peoples Republic of China, on 18–24 August 2009.demand, livestock products, quality, safety, developing countries, Consumer/Household Economics, Livestock Production/Industries,

Robust optimization based energy dispatch in smart grids considering demand uncertainty

In this study we discuss the application of robust optimization to the problem of economic energy dispatch in smart grids. Robust optimization based MPC strategies for tackling uncertain load demands are developed. Unexpected additive disturbances are modelled by defining an affine dependence between the control inputs and the uncertain load demands. The developed strategies were applied to a hybrid power system connected to an electrical power grid. Furthermore, to demonstrate the superiority of the standard Economic MPC over the MPC tracking, a comparison (e.g average daily cost) between the standard MPC tracking, the standard Economic MPC, and the integration of both in one-layer and two-layer approaches was carried out. The goal of this research is to design a controller based on Economic MPC strategies, that tackles uncertainties, in order to minimise economic costs and guarantee service reliability of the system.Postprint (author's final draft

PRICE DYNAMICS IN THE U.S. FIBER MARKETS:ITS IMPLICATIONS FOR COTTON INDUSTRY

The paper examines the price dynamics in the U.S. fiber market using error correction version of Granger causality test. Monthly prices are used to examine short-run and long-run price relationships simultaneously. Before specifying causal equations, time series properties of the prices are tested and are found to be first difference stationary and cointegrated. The causality results suggest weak lead-lag relationship between cotton and polyester prices in either direction. However, strongest relation is instantaneous feedback (within a month) between cotton and polyester prices. It may be interpreted from these results that any shock to the equilibrium relationships is mostly restored within a month. In addition, highly significant error correction terms in cotton and polyester equations also suggest the absence of distinct price leader which means both prices respond to restore equilibrium relationships.Production Economics,