David Hume's no-miracles argument begets a valid No-Miracles Argument

Hume's essay ‘Of Miracles’ has been a focus of controversy ever since its publication. The challenge to Christian orthodoxy was only too evident, but the balance-of-probabilities criterion advanced by Hume for determining when testimony justifies belief in miracles has also been a subject of contention among philosophers. The temptation for those familiar with Bayesian methodology to show that Hume's criterion determines a corresponding balance-of-posterior probabilities in favour of miracles is understandable, but I will argue that their attempts fail. However, I show that his criterion generates a valid form of the so-called No-Miracles Argument appealed to by modern realist philosophers, whose own presentation of it, despite their possession of the probabilistic machinery Hume himself lacked, is invalid.     

The problem of confirmation in the Everett interpretation

I argue that the Oxford school Everett interpretation is internally incoherent, because we cannot claim that in an Everettian universe the kinds of reasoning we have used to arrive at our beliefs about quantum mechanics would lead us to form true beliefs. I show that in an Everettian context, the experimental evidence that we have available could not provide empirical confirmation for quantum mechanics, and moreover that we would not even be able to establish reference to the theoretical entities of quantum mechanics. I then consider a range of existing Everettian approaches to the probability problem and show that they do not succeed in overcoming this incoherence.     

取有限个离散型随机变量似然估计的两种表达形式

对于离散型随机变量X来说,为了得到它的似然估计,就必须求得概率函数.该文对取得有限个值的离散型随机变量,给出了概率函数的两种表达形式.     

PM—空间中序结构及不动点定理

本文在概率度量空间(X,F)中引入半序结构“≤”、讨论了(X,≤)成为半序空间的条件,并证明了几个不动点定理。     

A comparative evaluation of objective and subjective weather forecasts in the united states

This paper is concerned primarily with the evaluation and comparison of objective and subjective weather forecasts. Operational forecasts of three weather elements are considered: (1) probability forecasts of precipitation occurrence, (2) categorical (i.e. non-probabilistic) forecasts of maximum and minimum temperatures and (3) categorical forecasts of cloud amount. The objective forecasts are prepared by numerical-statistical procedures, whereas the subjective forecasts are based on the judgements of individual forecasters. In formulating the latter, the forecasters consult information from a variety of sources, including the objective forecasts themselves. The precipitation probability forecasts are found to be both reliable and skilful, and evaluation of the temperature/cloud amount forecasts reveals that they are quite accurate/skilful. Comparison of the objective and subjective forecasts of precipitation occurrence indicates that the latter are generally more skilful than the former for shorter lead times (e.g. 12–24 hours), whereas the two types of forecasts are of approximately equal skill for longer lead times (e.g. 36–48 hours). Similar results are obtained for the maximum and minimum temperature forecasts. Objective cloud amount forecasts are more skilful than subjective cloud amount forecasts for all lead times. Examination of trends in performance over the last decade reveals that both types of forecasts for all three elements increased in skill (or accuracy) over the period, with improvements in objective forecasts equalling or exceeding improvements in subjective forecasts. The role and impact of the objective forecasts in the subjective weather forecasting process are discussed in some detail. The need to conduct controlled experiments and other studies of this process, with particular reference to the assimilation of information from different sources, is emphasized. Important characteristics of the forecasting system in meteorology are identified, and they are used to describe similarities and differences between weather forecasting and forecasting in other fields. Acquisition of some of these characteristics may be beneficial to other forecasting systems.     

运用概率论研究笔迹同一认定理论

笔迹的同一认定就是人身的同一认定，它在司法鉴定学中占有极其重要的地位。本文运用概率论中求随机事件交（或积）的概率的方法，建立了笔迹同一认定的一个判别式，从而定量地、系统地解决了司法鉴定学中笔迹同一认定这一难题。     

双基地雷达天线方向图损失分析

分析了双基地雷达目标回波的概率密度分布与接收角的关系 ,并推导了发射机工作在电扫和机械扫描方式下的双基地雷达天线方向图损失公式。对不同的双基地几何配置条件下的双基地天线方向图损失曲线进行了仿真。仿真结果显示 ,双基地雷达的天线方向图损失比单基地的要小。     

基于复合神经网络的数据分布模式仿真识别

采用复合结构神经网络对数据概率分布模式进行了仿真识别。首先提取数据的样本峰度、偏度、分位数和累积概率等数字特征 ,构建数据概率分布模式和仿真识别训练样本 ,然后采用Kohonen网络对概率分布进行聚类 ,接着运用BP网络对各聚类分别进行分类识别 ,最后对任意数据流进行了仿真识别。仿真识别结果表明 ,同其它模式识别方法相比 ,该方法更能够反映数据流概率分布的特征 ,从而得到了满意的模式识别效果。     

导弹射程和准备时间指标估值精度的计算方法

针对导弹射程和准备时间类指标的估值方法精度的描述及研究不足的现状 ,对导弹射程和准备时间指标估值精度进行了研究。在对估值方法分析研究的基础上 ,给出了满足正态分布随机变量容许限的非中心t -分布估值的精度要求。在估值精度要求条件下 ,推导出了满足估值精度要求的概率计算公式及计算方法 ,给出了计算用表。对导弹武器系统定型和部队作战使用具有参考价值     

对工科学生进行概率统计教学之我见

对工科学生进行概率统计的教学,教师首先要有一颗真正关爱学生的心,其次要有丰富充足的储备知识,最后要有多样的教学方法。本文针对工科学生的特点,通过理论陈述与生动实例相结合的方法,逐步讨论了如何才能在概率课上充分调动学生对概率的学习兴趣,激发学生的学习热情,利用学生的主观能动性,获得良好的教学效果。