Partial Identification of Economic Mobility: With an Application to the United States

Abstract

The economic mobility of individuals and households is of fundamental interest. While many measures of economic mobility exist, reliance on transition matrices remains pervasive due to simplicity and ease of interpretation. However, estimation of transition matrices is complicated by the well-acknowledged problem of measurement error in self-reported and even administrative data. Existing methods of addressing measurement error are complex, rely on numerous strong assumptions, and often require data from more than two periods. In this article, we investigate what can be learned about economic mobility as measured via transition matrices while formally accounting for measurement error in a reasonably transparent manner. To do so, we develop a nonparametric partial identification approach to bound transition probabilities under various assumptions on the measurement error and mobility processes. This approach is applied to panel data from the United States to explore short-run mobility before and after the Great Recession.     

脊波导宽频带电磁参数测试技术

针对高损耗介质材料电磁参数的宽频带测试问题,提出了利用脊波导进行测试的新方法,建立了电磁参数测试系统,并采用TRL技术进行了系统校准。该方法仅用3个波段的脊波导即可覆盖2.0～18.0GHz宽频带范围内的电磁参数测试,具有频带宽、体积小、测试精确度高等优点。     

无理数e在电路基本理论中出现的物理意义

对无理数e在电路分析中出现的几个典型例子作了分析讨论，明确指出：由1／e决定的特征常数可以在时间分布上和空间分布上，把一个按指数规律非均匀变化的问题，用一个等效的均匀变化的问题来表示；可以反映初始变化率与最终稳定值之间的联系；可以更深刻地反映某些物理过程的本质特征。     

非英语专业学生英语学习策略使用频率的研究

本调查以内蒙古工业大学非英语专业二年级的109名学生为样本,采取观察和问卷形式,考察非英语专业学生使用何种学习策略以及学习策略的使用频率.结果表明六种学习策略中,非英语专业学生最常用的策略是补偿策略,最不常用的策略是记忆策略.最后,作者指出本文的教学实践意义:即学习策略的培训应融于课堂教学中,其应用应体现于课堂教学活动中     

Projective Identification as a Contributor to Domestic Violence

Many explanations have been given as to why men batter. Rarely are deep unconscious intrapsychic processes identified as contributing reasons. One way that violent men may use their partner to fill emotional needs is through the primitive defense of projective identification. Projective identification may be invoked by men to induce the other partner to carry split off threatening parts of the self that are too anxiety provoking to retain. The occurrence of projective identification could therefore be an important intrapsychic and interpersonal dynamic that contributes to the escalation of tension prior to the violent episode.     

凯瑟琳爱情悲剧动因解析

凯瑟琳是《呼啸山庄》的女主角,凯瑟琳的爱是灵魂与肉体相脱离的情爱,充满不可调和的矛盾与冲突。她对希克厉的爱是精神之爱、灵魂之爱、自恋之爱,而对林敦的爱是肉体之爱、物化之爱、补偿之爱。凯瑟琳接受并爱着两个性格迥异的痴心汉,其对情爱的贪欲超过其心理承受的载荷,令其心理冲突绵延不辍。在两极爱欲的矛盾悖谬中,她忍受着精神的自我摧残,不只酿就了爱情悲剧,而且最终招致肉体的过早销亡。     

日本都道府县防灾无线网的建设及借鉴

日本是世界上灾害管理通信系统建设领先的国家,相关经验对我国灾害管理通信系统的建设有着重要的借鉴意义。都道府县防灾无线网是日本灾害管理通信系统的重要组成部分,已具备了较为成熟的建设模式和应用经验。本文介绍了日本灾害管理通信系统的框架、都道府县防灾无线网的体系架构及其通信系统组成,选择了神奈川县、长野县和三重县作为典型案例,对这三个县的防灾无线网的建设和应用情况作了分析,并借鉴日本的经验,结合我国的实际,提出了五个方面的建设建议。     

分析Chiral分层媒质特性的一般方法(英文)

提出了一套系统方法用于求解任意导体片位于界面的Chiral分层媒质的谐振频率,衰减因子和电磁场分布。文中的分析是在Fourier变换域的并矢格林函数和矩阵分析的基础上来进行的,给出的公式的最大价值在于它提供了求解Chiral分层媒质问题的方法论。     

Estimation of Metabolic Rate Constants in PBPK‐Models from Liver Slice Experiments: What Are the Experimental Needs?

A mechanistic model is presented describing the clearance of a compound in a precision-cut liver slice that is incubated in a culture medium. The problem of estimating metabolic rate constants in PBPK models from liver slice experiments is discussed using identifiability analysis. From the identifiability problem analysis, it appears that in addition to the clearance, the compound's free fraction in the slice and the diffusion rate of the exchange of the compound between culture medium and liver slice should be identified. In addition, knowledge of the culture medium volume, the slice volume, the compound's free fraction, and octanol-water-based partition between medium and slice is presupposed. The formal solution for identification is discussed from the perspective of experimental practice. A formally necessary condition for identification is the sampling of parent compound in liver slice or culture medium. However, due to experimental limitations and errors, sampling the parent compound in the slice together with additional sampling of metabolite pooled from the medium and the slice is required for identification in practice. Moreover, it appears that identification results are unreliable when the value of the intrinsic clearance exceeds the value of the diffusion coefficient, a condition to be verified a posteriori.     

A-H键振动频率与原子价层轨道能

本文研究了原子价层轨道能与共价型分子氢化物中A-H键的振动频率v_(A-H)的关系,结果表明二者间有良好的线性关系,其计算式为: v_(A-H)=-a∑n_1E_1/∑n_1(A)+b (1) V_(A-H)=-c∑n_1E_1/∑n~(B)+d (2)利用上式计算的振动频率V_(A-H)值接近于文献值。从而验证了用韩长日方法计算电负性的合理性。