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How Transparent Are Central Banks?
Central bank transparency has become the topic of a lively public and academic debate on monetary policy. Unfortunately, it has been complicated by the fact that transparency is a qualitative concept that is hard to measure. This paper proposes a comprehensive index for central bank transparency that comprises the political, economic, procedural, policy and operational aspects of central banking. The index is compiled for nine major central banks. It is based on a detailed analysis of actual information disclosure and reveals a rich variety in the degree and dynamics of central bank transparency
Subresultants in multiple roots: an extremal case
We provide explicit formulae for the coefficients of the order-d polynomial
subresultant of (x-\alpha)^m and (x-\beta)^n with respect to the set of
Bernstein polynomials \{(x-\alpha)^j(x-\beta)^{d-j}, \, 0\le j\le d\}. They are
given by hypergeometric expressions arising from determinants of binomial
Hankel matrices.Comment: 18 pages, uses elsart. Revised version accepted for publication at
Linear Algebra and its Application
Combining quantitative narrative analysis and predictive modeling - an eye tracking study
As a part of a larger interdisciplinary project on Shakespeare sonnets’ reception (Jacobs et al., 2017; Xue et al., 2017), the present study analyzed the eye movement behavior of participants reading three of the 154 sonnets as a function of seven lexical features extracted via Quantitative Narrative Analysis (QNA). Using a machine learning- based predictive modeling approach five ‘surface’ features (word length, orthographic neighborhood density, word frequency, orthographic dissimilarity and sonority score) were detected as important predictors of total reading time and fixation probability in poetry reading. The fact that one phonological feature, i.e., sonority score, also played a role is in line with current theorizing on poetry reading. Our approach opens new ways for future eye movement research on reading poetic texts and other complex literary materials (cf. Jacobs, 2015c)
The Impact of Investments in Maize Research and Dissemination in Zambia Part I: Main Report
Michigan State University (MSU) is currently assessing the impact of agricultural research on various commodities in seven African countries: Cameroon (maize, cowpea, sorghum), Kenya (maize, wheat), Malawi (maize), Mali (maize), Niger (sorghum, cowpea, millet), Uganda (oilseeds), and Zambia (maize). These countries were selected because they represent a variety of agro-ecological regions, and because their research systems have received significant levels of funding from USAID. The country studies undertaken by MSU are part of a series of research works recently commissioned to help USAID and the U.S. Congress analyze the effectiveness of aid given to strengthen national agricultural research systems in Africa. In Zambia, MSU collaborated with the Ministry of Agriculture, Food and Fisheries (MAFF) and the University of Zambia's Rural Development Studies Bureau (RDSB) to assess the impact of investments in maize research and dissemination made during the late 1970s and early 1980s. This research resulted in the release of ten new hybrids and open-pollinated varieties between 1984-88. Major support for maize research and dissemination came from the Government of Zambia (GRZ), the Centro Internaciónal de Mejoramiento de Maiz y Trigo (CIMMYT), the Food and Agriculture Organization/United Nations Development Program (FAO/UNDP), the Swedish International Development Authority (SIDA) and the United States Agency for International Development (USAID).food security, food policy, maize, Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies, Downloads July 2008 - June 2009: 19, Q18,
Fetal-maternal outcomes of induction of labour among women delivered at regional referral hospitals in Dar es Salaam Tanzania
Purpose: Africa has a very low rate of induction of labour with high maternal and perinatal morbidity and mortality. However fetal-maternal outcomes following induction of labour are not well documented in Tanzania. This study aimed to assess fetal-maternal outcomes following induction of labour among women delivered at Dar es Salaam regional referral hospitals in Tanzania.Design/methodology/Approach: A total of 301 expectant mothers were recruited in a prospective observational study conducted at all regional referral hospitals in Dar es Salaam, Tanzania. Data on fetal-maternal outcomes were collected using a pre-designed clinical sheet. Demographic data, obstetric history, methods as well as outcomes of labour induction were recorded. The continuous variables were summarized using the median and corresponding interquartile range. Categorical variables were summarized using frequency and proportions and the significance of differences were assessed using Chi-square at P<0.05.Results: The leading methods for induction of labour were Oxytocin (48.5%) and a combination of Folley’s catheter with Oxytocin (28.4%). Induction of labour significantly improved fetal outcomes at birth P<0.05. Induction of labour associated with improved Apgar scores in newborn babies. Failure of induction of labour was the largest contributor to the increased Caesarean Section rate observed in this study.Research limitation/Implication: This study has therefore explored the fetal-maternal outcomes following induction of labour in Tanzanian regional referral hospitals.Practical implication: Induction of labour improves and minimizes neonatal complications in referral regional hospitals in Dar es Salaam.Originality/Value: These findings fill a gap of information which was missing on the fetalmaternal outcomes following induction of labour among expectant mothers in Dar es Salaam regional referral hospitals
System Identification of an on Orbit Spacecraft\u27s Antenna Dynamics
As a result of previous efforts [Pachter, Barba, 2007] a tight control loop was designed to meet performance specifications while minimizing the feedback control system’s gains of a spacecraft mounted flexible antenna. Emphasis is now shifted to on orbit system identification of the antenna dynamics in order to increase nominal plant knowledge, estimate plant uncertainty bounds, as well as determine the disturbance band. Non-parametric system identification is undertaken. Knowledge of the plant dynamics along with the corresponding uncertainty bounds will provide for the design of a control system which meets the specifications (tracking and disturbance rejection) while at the same time employing the lowest possible gain. This in turn is conducive to sensor noise disturbance rejection, avoidance of actuator saturation, and excitation of high frequency modes
Lexical Borrowing in the Middle English period: A multi-domain analysis of semantic outcomes
The Middle English period is well known as one of widespread lexical borrowing from French and Latin, and scholarly accounts traditionally assume that this influx of loanwords caused many native terms to shift in sense or to drop out of use entirely. The study analyses an extensive dataset, tracking patterns in lexical retention, replacement and semantic change, and comparing long-term outcomes for both native and non-native words. Our results challenge the conventional view of competition between existing terms and foreign incomers. They show that there were far fewer instances of relexification, and far more of synonymy, during the Middle English period than might have been expected. When retention rates for words first attested between 1100-1500 are compared, it is loanwords, not native terms, which are more likely to become obsolete at any point up to the nineteenth century. Furthermore, proportions of outcomes involving narrowing and broadening (often considered common outcomes following the arrival of a co-hyponym in a semantic space) were low in the Middle English period, regardless of language of origin
Applying Landscape-scale Modeling to Everglades Restoration
In this dissertation I describe the implementation and application of three spatially-explicit, landscape-scale models designed to address specific aspects of Everglades restoration. The first is a model of vegetation succession for the Everglades. The second is a fire model for the Everglades. The third is a model of the spread and optimal spatial control of an invasive, non-native plant.
I developed the succession and fire models as part of the Across Trophic Level System Simulation (ATLSS). These models are used to assess the relative effects of alternative hydrology scenarios on the distribution of vegetation and fires. In addition to the effect of hydrology, I also included the effects of fires and nutrients in the succession model. It is the first model to include the effects of multiple interacting environmental processes on landscape-scale patterns of vegetation succession. I based the fire model on a percolation process including the effects of hydrology, fire history and dynamic vegetation patterns. These two models are linked to each other and incorporate both direct and indirect effects of hydrology and feedbacks between fires and succession. The fire model is the first such model to be linked to a dynamic vegetation model. I present model results for three hydrology scenarios. Results indicate that the differences in the management of hydrology under these scenarios are small. I describe a sensitivity analysis of major fire model parameters and compare the fire model outputs to historical fire data.
The third model addresses the optimal spatial control of the invasive fern, Lygodium microphyllum, in the Arthur R. Marshall Loxahatchee National Wildlife Refuge. The model is the first to examine the spatial optimal control of an invasive species at the landscape-scale. I applied a genetic algorithm to search for optimal treatment plans. I compare results of the optimization to a standard treatment approach for a range of budgets. Results from this model indicate that the genetic algorithm implemented is not capable of carrying out a landscape-scale optimization. However, results from the standard treatment approach provide insights into the potential funding levels required to control and eliminate L. microphyllum from Loxahatchee
Geometric approach to non-relativistic Quantum Dynamics of mixed states
In this paper we propose a geometrization of the non-relativistic quantum
mechanics for mixed states. Our geometric approach makes use of the Uhlmann's
principal fibre bundle to describe the space of mixed states and as a novelty
tool, to define a dynamic-dependent metric tensor on the principal manifold,
such that the projection of the geodesic flow to the base manifold gives the
temporal evolution predicted by the von Neumann equation. Using that approach
we can describe every conserved quantum observable as a Killing vector field,
and provide a geometric proof for the Poincare quantum recurrence in a physical
system with finite energy levels.Comment: 19 pages, 1 figure. Minor corrections. Accepted to Journal of
Mathematical Physic
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