Probabilistic prediction with constant change of success

1989 ◽  
Vol 136 (4-5) ◽  
pp. 183-187 ◽  
Author(s):  
Johann Summhammer
2019 ◽  
Vol 10 (7) ◽  
pp. 585-605
Author(s):  
Terrence Thomas ◽  
◽  
Befikadu Legesse ◽  
Cihat Gunden ◽  
◽  
...  

The failure of top-down categorical approaches for generating solutions to many local problems has led to the adoption of alternate approaches. Many scholars believe that a confluence of local and global forces have generated complex problems, which call for new approaches to problem solving. Previously, the top-down approach relied entirely on the knowledgeable elite. Communities were seen as passive study subjects and information flow was one way only- from knowledgeable elites to the less knowledgeable community agents or community-based organization acting on behalf of communities. The objectives of this study are to provide a review of governance as a means of organizing community action to address community problems in the Black Belt Region (BBR) of the Southeastern United States, and an assessment of community problems in the BBR from the perspectives of community-based organizations (CBOs). Data was collected from CBOs via a telephone survey in eleven Southeastern states and via listening sessions conducted with CBOs in 9 Southeastern states. The study provides valuable insight regarding the challenges faced by these organizations and strategies they employ in adapting to serve their communities.


Author(s):  
Steven Howlett

Volunteering extends into almost every facet of life but the circumstances in which it takes place are subject to almost constant change. Historical roots of altruistic, charitable, and campaigning behaviours are still evident, but the importance of different motivations maybe be altering. Organizations involving volunteers seek to understand volunteer motivations and to find better ways to manage volunteers. And yet there is still disagreement as to how far management techniques from paid work are suitable for volunteers. Meanwhile, the reach of government seems ever stronger as volunteering continues to offer ways to affirm what it means to be a participatory citizen and to provide a considerable resource to stretched welfare budgets. This chapter looks at these points with a view to introducing how these challenges shape the chapters that follow.


Oxford Studies in Ancient Philosophy provides, twice each year, a collection of the best current work in the field of ancient philosophy. Each volume features original essays that contribute to an understanding of a wide range of themes and problems in all periods of ancient Greek and Roman philosophy, from the beginnings to the threshold of the Middle Ages. From its first volume in 1983, OSAP has been a highly influential venue for work in the field, and has often featured essays of substantial length as well as critical essays on books of distinctive importance. Volume LV contains: a methodological examination on how the evidence for Presocratic thought is shaped through its reception by later thinkers, using discussions of a world soul as a case study; an article on Plato’s conception of flux and the way in which sensible particulars maintain a kind of continuity while undergoing constant change; a discussion of J. L. Austin’s unpublished lecture notes on Aristotle’s Nicomachean Ethics and his treatment of loss of control (akrasia); an article on the Stoics’ theory of time and in particular Chrysippus’ conception of the present and of events; and two articles on Plotinus, one that identifies a distinct argument to show that there is a single, ultimate metaphysical principle; and a review essay discussing E. K. Emilsson’s recent book, Plotinus.


2020 ◽  
Vol 10 (10) ◽  
pp. 275
Author(s):  
Ernesto Colomo-Magaña ◽  
Roberto Soto-Varela ◽  
Julio Ruiz-Palmero ◽  
Melchor Gómez-García

In a digital and interconnected context, where educational processes are in constant change, active methodologies take on a relevant role by making students the protagonists of their learning. Among the different possibilities, the flipped classroom stands out for its time optimization, the incorporation of technological resources, and the personalization of the processes. The aim of this research is to analyze the perception of higher education students about the usefulness of the flipped classroom as a methodology. The information was collected with a validated instrument, which was applied to a sample of 123 students from the Faculty of Educational Sciences of the University of Málaga (Spain). A positive evaluation of the usefulness of the flipped classroom as a learning methodology was reflected in the results, highlighting its instrumental dimension. Significant differences were perceived regarding the usefulness of the flipped classroom for the promotion of autonomous learning, which had a superior valuation according to women. In conclusion, the flipped classroom stands as a methodological alternative to promote learning that has a positive evaluation from the students that made up the sample.


Aerospace ◽  
2021 ◽  
Vol 8 (2) ◽  
pp. 29
Author(s):  
Stanley Förster ◽  
Michael Schultz ◽  
Hartmut Fricke

The air traffic is mainly divided into en-route flight segments, arrival and departure segments inside the terminal maneuvering area, and ground operations at the airport. To support utilizing available capacity more efficiently, in our contribution we focus on the prediction of arrival procedures, in particular, the time-to-fly from the turn onto the final approach course to the threshold. The predictions are then used to determine advice for the controller regarding time-to-lose or time-to-gain for optimizing the separation within a sequence of aircraft. Most prediction methods developed so far provide only a point estimate for the time-to-fly. Complementary, we see the need to further account for the uncertain nature of aircraft movement based on a probabilistic prediction approach. This becomes very important in cases where the air traffic system is operated at its limits to prevent safety-critical incidents, e.g., separation infringements due to very tight separation. Our approach is based on the Quantile Regression Forest technique that can provide a measure of uncertainty of the prediction not only in form of a prediction interval but also by generating a probability distribution over the dependent variable. While the data preparation, model training, and tuning steps are identical to classic Random Forest methods, in the prediction phase, Quantile Regression Forests provide a quantile function to express the uncertainty of the prediction. After developing the model, we further investigate the interpretation of the results and provide a way for deriving advice to the controller from it. With this contribution, there is now a tool available that allows a more sophisticated prediction of time-to-fly, depending on the specific needs of the use case and which helps to separate arriving aircraft more efficiently.


2020 ◽  
Vol 2020 ◽  
pp. 1-18 ◽  
Author(s):  
Guozhu Cheng ◽  
Rui Cheng ◽  
Yulong Pei ◽  
Liang Xu

To predict the probability of roadside accidents for curved sections on highways, we chose eight risk factors that may contribute to the probability of roadside accidents to conduct simulation tests and collected a total of 12,800 data obtained from the PC-crash software. The chi-squared automatic interaction detection (CHAID) decision tree technique was employed to identify significant risk factors and explore the influence of different combinations of significant risk factors on roadside accidents according to the generated decision rules, so as to propose specific improved countermeasures as the reference for the revision of the Design Specification for Highway Alignment (JTG D20-2017) of China. Considering the effects of related interactions among different risk factors on roadside accidents, path analysis was applied to investigate the importance of the significant risk factors. The results showed that the significant risk factors were in decreasing order of importance, vehicle speed, horizontal curve radius, vehicle type, adhesion coefficient, hard shoulder width, and longitudinal slope. The first five important factors were chosen as predictors of the probability of roadside accidents in the Bayesian network analysis to establish the probability prediction model of roadside accidents. Eventually, the thresholds of the various factors for roadside accident blackspot identification were given according to probabilistic prediction results.


1911 ◽  
Vol 14 (3) ◽  
pp. 217-234 ◽  
Author(s):  
G. Canby Robinson ◽  
George Draper

In hearts showing auricular fibrillation mechanical stimulation of the right vagus nerve causes, as a rule, marked slowing or stoppage of ventricular rhythm, without producing any appreciable effect in the electrocardiographic record of the auricular fibrillation. The ventricular pauses are apparently due to the blocking of stimuli from the auricles. The force of ventricular systole is distinctly weakened for several beats after vagus stimulation, and ectopic ventricular systoles have been seen in several instances, apparently the result of the vagus action. There may, in some cases, be lowered excitability of the ventricles, while no constant change is seen in the size of the electrical complexes representing ventricular systole.


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