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We study, from the standpoint of coherence, comparative probabilities on an arbitrary familyE of conditional events. Given a binary relation ·, coherence conditions on · are related to de Finetti's coherent betting system: we consider their connections to the usual properties of comparative probability and to the possibility of numerical representations of ·. In this context, the numerical reference frame is that of de Finetti's coherent subjective conditional probability, which is not introduced (as in Kolmogoroff's approach) through a ratio between probability measures.Another relevant feature of our approach is that the family & need not have any particular algebraic structure, so that the ordering can be initially given for a few conditional events of interest and then possibly extended by a step-by-step procedure, preserving coherence.  相似文献   
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Industrial statistics plays a major role in the areas of both quality management and innovation. However, existing methodologies must be integrated with the latest tools from the field of Artificial Intelligence. To this end, a background on the joint application of Design of Experiments (DOE) and Machine Learning (ML) methodologies in industrial settings is presented here, along with a case study from the chemical industry. A DOE study is used to collect data, and two ML models are applied to predict responses which performance show an advantage over the traditional modeling approach. Emphasis is placed on causal investigation and quantification of prediction uncertainty, as these are crucial for an assessment of the goodness and robustness of the models developed. Within the scope of the case study, the models learned can be implemented in a semi-automatic system that can assist practitioners who are inexperienced in data analysis in the process of new product development.  相似文献   
4.
We formulate and investigate experimentally a model of how individuals choose between time sequences of monetary outcomes. The model assumes that a decision maker uses, sequentially, two criteria to screen options. Each criterion only permits a decision between some pairs of options, while the other options are incomparable according to that criterion. When the first criterion is not decisive, the decision maker resorts to the second criterion to select an alternative. We find that: (1) traditional economic models based on discounting alone cannot explain a significant (almost 30%) proportion of the data no matter how much variability in the discount functions is allowed; (2) our model, despite considering only a specific (exponential) form of discounting, can explain the data much better solely thanks to the use of the secondary criterion; (3) our model explains certain specific patterns in the choices of the “irrational” people. We reject the hypothesis that anomalous behavior is due simply to random “mistakes” around the basic predictions of discounting theories: deviations are not random and there are clear systematic patterns of association between “irrational” choices.  相似文献   
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Most studies of quality improvement deal with ordered categorical data from industrial experiments. Accounting for the ordering of such data plays an important role in effectively determining the optimal factor level of combination. This paper utilizes the correspondence analysis to develop a procedure to improve the ordered categorical response in a multifactor state system based on Taguchi's statistic. Users may find the proposed procedure in this paper to be attractive because we suggest a simple and also popular statistical tool for graphically identifying the really important factors and determining the levels to improve process quality. A case study for optimizing the polysilicon deposition process in a very large-scale integrated circuit is provided to demonstrate the effectiveness of the proposed procedure.  相似文献   
7.

Under the pressure of population aging the Italian pension system has undergone reforms to increase labor force participation and retirement age, and, thus, the length of working life. However, how the duration of working life has developed in recent years is not well understood. This paper is the first to analyze trends in working life expectancy in Italy. We use data from a nationally representative longitudinal sample of 880,000 individuals from 2003 to 2013 and estimate working life expectancy by gender, occupational category, and region of residence using a Markov chain approach. We document large and increasing heterogeneity in the length of working life. From 2003–2004 to 2012–2013, working life expectancy for men declined from 35.2 to 27.2 years and for women from 34.7 to 23.7 years, increasing the gender gap to 3.5 years. Both young and old were hit, as roughly half of the decline was attributable to ages below 40, half above 40. Working life expectancy declined for all occupational groups, but those in manual occupations lost most, 8.5 years (men) and 10.5 years (women). The North–South economic gradient widened such that men living in the North were expected to work 8 years longer than women living in the South. The fraction of working life of total life expectancy at age 15 declined to record lows at 40% for men and 34% for women in 2012–2013. Policies aiming at increasing total population working life expectancy need to take into consideration the socio-demographic disparities highlighted by our results.

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ABSTRACT

Residential care is one of the most restrictive out-of-home care settings; however, this is a temporary placement and youth eventually reintegrate into the home and community setting. Reintegration presents many challenges, and aftercare becomes critical for maintaining youth gains and promoting family stability. Aftercare programs and supports should align to individual family needs that entail understanding individual and familial characteristics. Previous studies have explored characteristics related to family functioning, mental health, behavior, and perceptions of need during reintegration; yet little is known regarding how affective characteristics (i.e., self-efficacy, empowerment) factor into reintegration, or the implications this may have for providers. The purpose of this study was to address this gap by exploring empowerment and self-efficacy in caregivers (= 120) who had a child return home within 1 month of departing residential care. Overall, caregivers reported high levels of empowerment and self-efficacy during the initial transition period. Significant differences for empowerment and self-efficacy were present in characteristics such as race, income, number of children in the home, and free/reduced lunch status.  相似文献   
9.
The psycho-physical stress is a risk to all intents and purposes,finally acknowledged, it requires increasing attention. Measures forits protection are reflected in the appropriate application of organizational policies on a human scale, or in respect of the"macro-ergonomics". This work consists on several inter-disciplinary tools available to the proper prevention, outbreaks of work-related stress.During work, adequate rests are important to prevent work related physical and mental fatigue. The strategies for maintaining a healthy balance between work rate and work breaks, may differ depending on the individual, subjective habits and peculiarities related to the work environment. Resting does not necessarily mean "going to break". The break-time is important as the work-time. While the latter is regulated, the first is not always clearly defined, though necessary. Knowing the employment contract is the first step towards the implementation of their rights relating to periods of suspension from the activity of work is also essential for high performance working. Breathing exercises, massage therapy, biofeedback, role-playing are some of the tools used during work breaks to prevent mental and physical fatigue. At the end music has a rhythm by alternating strong and weak accents. If the musical notes represent the "vertical" trend of music (melody), figures and pauses, inserted into the rhythmic structure of the measure, regulate the duration of sounds over time and determine the "horizontal" trend of a song. Transferring this concept on work, is meant to understand, using a metaphor, the importance of respect of changes in both vertical and horizontal trends inside a cycle.  相似文献   
10.
A reference method to estimate Feral Pigeon (C. livia) population size in urban areas is missing: results of different surveys are difficult to compare due to the wide heterogeneity of approaches. A combined technique, the Superimposed Urban Strata (SUS) method, especially designed to estimate pigeon population size in urban areas, is proposed. SUS implements methods based on stratified sampling layers: its reliability was tested with a pilot study in Padua (Italy). The survey area was split into two superimposed strata and a different survey technique was applied to each stratum. The first stratum consisted of twelve topographic sampling units, identified as critical ornithic-density loci. The second stratum was obtained by selecting 10 % of the survey area with systematic sampling. In the estimate of the population size, different detection probabilities were assigned to the two strata. The SUS method was first applied in 2007, when three-year growth projections for the C. livia population were calculated, with a density-dependent model. In 2010, the survey was repeated to countercheck previous data. Estimated C. livia population size was of 2340 ±93 units in 2007, whereas in 2010 it was of 3679 ±161 units. The 2010 estimated population size resulted in fair accordance with the three-year projections, showing less than a 4 % mismatch. SUS proved to be an adequate estimate method for urban areas: so far it has been tested only in an average Italian urban area, but it could be easily adapted to other cities by calibrating parameters linked to the peculiar urban background.  相似文献   
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