The Application of Sparse Clustering Algorithm in Chinese Stock Market

随着中国人日常生活水平的提高，人们已不再满足于拿固定的工资，越来越多的公民选择将自己手中的资金投资到股票市场，希望能够钱生钱。但并非所有股民都是金融专业人员，如何进行股票种类的选择与资金的分配已经成为越来越多的中国人所希望知道的问题。选择股票的两个基本原则就是低风险、高收益，那么如何在上万只股票中选择最适合自己的股票，如何缩小选择范围，如在某个行业内选择股票是本文所希望解决的问题。 众所周知，股票数据是动态的，随时间的推移而不断变化，因此传统分析股票的方法为时间序列分析法，基于随机过程理论和数理统计学方法，找出股票数据的内在规律，以解决实际应用的问题。时间序列分析最大的优点是实际数据的时间序...With the development of quality of lives among Chinese people, more and more citizens are no longer satisfied with the mere salaries, many of them choose to turn to the stock market to make their money derive larger amount of money. However, not everyone is professional in finance, most of them need advice on how to choose stocks and how to allocate their capital. Two basic principles of choosing ...学位：经济学硕士院系专业：经济学院_统计学学号：1542013115203

Reflections on Conventional Statistics in the Big Data Era

本文在大数据时代背景下,将统计学与大数据有机结合,剖析了大数据时代给统计学带来的变革,阐述了大数据为传统统计学带来的发展机遇。为了保持统计学旺盛的生命力,本文对统计学的发展提出了几点思考。In this paper,statistics and big data are integrated based on the operation of conventional statistics. We analyze the changes and development opportunities brought by big data to statistics. Also,in order to keep active,we propose some suggestions on the development of statistics.国家社会科学基金项目重大项目“大数据与统计学理论的发展研究”(13&ZD148);; 国家统计局统计科学研究所研究基地项目“网络舆情分析的统计方法及其应用”(201407)资

Geographical identification of Larimichthys crocea based on analysis of elements and stable isotope ratios(基于元素及稳定同位素分析的大黄鱼产地区分技术)

为实现对4种大黄鱼（Larimichthys crocea）产地（分别来自福建宁德养殖、浙江温州养殖、浙江舟山养殖和舟山渔场自然海域捕捞）的区分，应用电感耦合等离子体质谱仪（inductively coupled plasma mass spectrometry，ICP-MS）及元素分析-同位素质谱仪对大黄鱼肌肉中19种矿物元素及δ13C、δ15N和C、N元素的质量分数进行了测定，基于质量分数差异并结合主成分分析（principal component analysis，PCA）、聚类分析（cluster analysis，CA）和Fisher判别分析对4种不同产地大黄鱼进行区分。单因素方差分析（ANOVA）及事后多重比较（LSD和Tamhane T2检验）结果表明，12种元素（C、N、Mg、Al、K、Ti、Cr、Cu、Zn、Se、Sn、Ba）及δ13C、δ15N在不同产地大黄鱼中具有较明显的地域特征差异。PCA结果表明，前2个主成分（累计方差贡献率为64.1%）的得分散点图分成了4个相对集中的区域，4种不同产地大黄鱼彼此无重叠，能被有效区分。CA结果表明，4种不同产地大黄鱼中除温州养殖大黄鱼样本被分为两类，其他3种大黄鱼样本均各自聚为一类。Fisher判别分析结果显示，原始分类结果的判别准确率为100%，“留一法”交叉验证分类结果显示，有85.7%的舟山养殖大黄鱼样本被正确分类，14.3%的被误判为温州养殖大黄鱼，其余3种大黄鱼样本分类准确率均为100%。研究结果表明，利用元素及稳定同位素比值差异结合化学计量学分析手段，可有效实现大黄鱼的产地区分，为大黄鱼产地鉴别提供参考

Systematic Korea Microlensing Telescope Network planetary anomaly search – III. One wide-orbit planet and two stellar binaries

ABSTRACT Only a few wide-orbit planets around old stars have been detected, which limits our statistical understanding of this planet population. Following the systematic search for planetary anomalies in microlensing events found by the Korea Microlensing Telescope Network, we present the discovery and analysis of three events that were initially thought to contain wide-orbit planets. The anomalous feature in the light curve of OGLE-2018-BLG-0383 is caused by a planet with mass ratio q = 2.1 × 10−4 and a projected separation s = 2.45. This makes it the lowest mass-ratio microlensing planet at such wide orbits. The other two events, KMT-2018-BLG-0998 and OGLE-2018-BLG-0271, are shown to be stellar binaries (q &amp;gt; 0.1) with rather close (s &amp;lt; 1) separations. We briefly discuss the properties of known wide-orbit microlensing planets and show that the survey observations are crucial in discovering and further statistically constraining such a planet population.</jats:p

Determination of the number of ψ(3686) events taken at BESIII

The number of ψ(3686) events collected by the BESIII detector during the 2021 run period is determined to be (2259.3±11.1)×106 by counting inclusive ψ(3686) hadronic events. The uncertainty is systematic and the statistical uncertainty is negligible. Meanwhile, the numbers of ψ(3686) events collected during the 2009 and 2012 run periods are updated to be (107.7±0.6)×106 and (345.4±2.6)×106, respectively. Both numbers are consistent with the previous measurements within one standard deviation. The total number of ψ(3686) events in the three data samples is (2712.4±14.3)×10^