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acreg: Arbitrary correlation regression acreg:任意相关回归
IF 4.8 2区 数学 Q1 Mathematics Pub Date : 2023-03-01 DOI: 10.1177/1536867X231162031
Fabrizio Colella, R. Lalive, S. Sakalli, Mathias Thoenig
We present acreg, a new command that implements the arbitrary clustering correction of standard errors proposed in Colella et al. (2019, IZA discussion paper 12584). Arbitrary here refers to the way observational units are correlated with each other: we impose no restrictions so that our approach can be used with a wide range of data. The command accommodates both cross-sectional and panel databases and allows the estimation of ordinary least-squares and two-stage least-squares coefficients, correcting standard errors in three environments: in a spatial setting using units’ coordinates or distance between units, in a network setting starting from the adjacency matrix, and in a multiway clustering framework taking multiple clustering variables as input. Distance and time cutoffs can be specified by the user, and linear decays in time and space are also optional.
我们提出了一种新的命令acreg,它实现了Colella等人提出的标准误差的任意聚类校正。(2019,IZA讨论论文12584)。这里的任意性指的是观测单位之间的相互关联方式:我们不施加任何限制,这样我们的方法就可以用于广泛的数据。该命令同时容纳横截面和面板数据库,并允许估计普通最小二乘和两阶段最小二乘系数,纠正三种环境中的标准误差:在使用单位坐标或单位之间距离的空间设置中,在从邻接矩阵开始的网络设置中,以及在以多个聚类变量作为输入的多路聚类框架中。用户可以指定距离和时间截止,时间和空间中的线性衰减也是可选的。
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引用次数: 1
Two-tier stochastic frontier analysis using Stata 基于Stata的两层随机前沿分析
IF 4.8 2区 数学 Q1 Mathematics Pub Date : 2023-03-01 DOI: 10.1177/1536867X231162033
Yujun Lian, Chang Liu, Christopher F. Parmeter
In this article, we introduce the sftt command, which fits two-tier stochastic frontier (2TSF) models with cross-sectional data. Like most frontier models, a 2TSF model consists of a linear frontier model and a composite error term. The error term is assumed to be a mixture of three components: two onesided inefficiency terms—strictly nonnegative and nonpositive, respectively—and a symmetric noise term. When providing appropriate distributional assumptions, sftt can fit models with exponential and half-normal specifications. sftt also fits 2TSF models with the scaling property to mitigate concerns over distributional specifications. In addition, we provide two subcommands, sftt sigs and sftt eff, to assist in postestimation efficiency analysis. We provide an overview of the 2TSF literature, a description of the sftt command and its options, and examples using simulated and actual data.
在本文中,我们介绍了sftt命令,它适用于具有横截面数据的双层随机前沿(2TSF)模型。与大多数前沿模型一样,2TSF模型由线性前沿模型和复合误差项组成。误差项被假设为三个分量的混合物:两个单边低效项——分别是严格非负和非正的——和一个对称噪声项。当提供适当的分布假设时,sftt可以拟合具有指数和半正态规范的模型。sftt还适用于具有缩放特性的2TSF模型,以减轻对分布式规范的担忧。此外,我们还提供了两个子命令,sftt-sigs和sftt-eff,以帮助进行后估计效率分析。我们提供了2TSF文献的概述、sftt命令及其选项的描述,以及使用模拟和实际数据的示例。
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引用次数: 1
Announcement of the Stata Journal Editors’ Prize 2023 Stata期刊编辑奖公告2023
IF 4.8 2区 数学 Q1 Mathematics Pub Date : 2023-03-01 DOI: 10.1177/1536867X231160122
N. Cox, S. Jenkins
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引用次数: 0
Stata tip 150: When is it appropriate to xtset a panel dataset with panelvar only? Stata提示150:什么时候只使用panelvar来xtset面板数据集是合适的?
IF 4.8 2区 数学 Q1 Mathematics Pub Date : 2023-03-01 DOI: 10.1177/1536867X231162020
Carlo Lazzaro
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引用次数: 0
Stata tip 151: Puzzling out some logical operators Stata提示151:搞懂一些逻辑运算符
IF 4.8 2区 数学 Q1 Mathematics Pub Date : 2023-03-01 DOI: 10.1177/1536867x231162009
N. Cox
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引用次数: 0
portfolio: A command for conducting portfolio analysis in Stata portfolio:在Stata中执行投资组合分析的命令
IF 4.8 2区 数学 Q1 Mathematics Pub Date : 2022-12-01 DOI: 10.1177/1536867X221141021
Hongbing Zhu, Lihua Yang
Portfolio analysis is widely used in empirical asset pricing to explore the cross-sectional relation between two or more variables. In this article, we introduce the methodology of portfolio analysis and describe a new command, portfolio, that provides a one-step solution for portfolio analysis. portfolio calculates the equal- or value-weighted returns with a t statistic for the portfolio and tests the significance of a long-short strategy in portfolios. portfolio also provides the Newey–West standard-error adjustment option for alleviating the impact of potential autocorrelation and heteroskedasticity in financial time series.
在实证资产定价中,投资组合分析被广泛用于探索两个或多个变量之间的横截面关系。在本文中,我们介绍了投资组合分析的方法,并描述了一个新的命令portfolio,它为投资组合分析提供了一步解决方案。Portfolio用t统计量计算投资组合的等额或价值加权收益,并检验多空策略在投资组合中的重要性。投资组合还提供了新西标准误差调整选项,以减轻金融时间序列中潜在的自相关和异方差的影响。
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引用次数: 0
Estimating the risk of events with stprisk 评估突发事件的风险
IF 4.8 2区 数学 Q1 Mathematics Pub Date : 2022-12-01 DOI: 10.1177/1536867X221141057
M. Bottai
Incidence rates are popular summary measures of the occurrence over time of events of interest. They are also called mortality rates or failure rates, depending on the context. The incidence rate is defined as the ratio between the total number of events and total follow-up time and can be estimated with the strate command. When the event of interest can occur multiple times on any given subject over a time period, like infections, the incidence rate represents an average count per unit of time, such as the average number of infections per year. When the event of interest can occur only once, such as death, an alternative summary measure is the risk, or probability, of occurrence per unit time, such as the risk of dying in one year. In this article, I present the stprisk command, which estimates risks, and illustrate its use and interpretation through a data example.
发病率是衡量感兴趣事件发生时间的常用汇总指标。根据具体情况,它们也被称为死亡率或失败率。发病率定义为事件总数与总随访时间之间的比率,可以使用strate命令进行估计。当感兴趣的事件在一段时间内可能在任何给定的受试者身上发生多次时,如感染,发病率表示每单位时间的平均计数,如每年的平均感染人数。当感兴趣的事件只能发生一次,例如死亡时,另一种汇总指标是单位时间内发生的风险或概率,例如一年内死亡的风险。在本文中,我介绍了用于估计风险的stprisk命令,并通过一个数据示例说明了它的使用和解释。
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引用次数: 0
Stata tip 147: Porting downloaded packages between machines Stata技巧147:在机器之间移植下载的包
IF 4.8 2区 数学 Q1 Mathematics Pub Date : 2022-12-01 DOI: 10.1177/1536867X221141067
R. Newson
Stata, like R and Genstat, is a statistical language with potentially as many dialects as users. These dialects are defined by the optional packages that each user has downloaded; the number may be hundreds for a high-power user. This is a major advantage of a statistical language (such as Stata) over a statistical package (such as SPSS). And Stata users would like to continue to have that advantage on web-disabled machines.
与R和Genstat一样,Stata是一种统计语言,其方言可能与用户一样多。这些方言是由每个用户下载的可选包定义的;对于高功率用户来说,该数字可以是数百。这是统计语言(如Stata)相对于统计软件包(如SPSS)的主要优势。Stata用户希望在禁用网络的机器上继续拥有这一优势。
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引用次数: 0
Software Updates 软件更新
IF 4.8 2区 数学 Q1 Mathematics Pub Date : 2022-12-01 DOI: 10.1177/1536867x221141069
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引用次数: 0
Conditional evaluation of predictive models: The cspa command 预测模型的条件求值:cspa命令
IF 4.8 2区 数学 Q1 Mathematics Pub Date : 2022-12-01 DOI: 10.1177/1536867X221141014
Z. Liao, R. Quaedvlieg, W. Zhou
In this article, we introduce a new command, cspa, that implements the conditional superior predictive ability test developed in Li, Liao, and Quaedvlieg (2022, Review of Economic Studies 89: 843–875). With the conditional performance of predictive methods measured nonparametrically by the conditional expectation functions of their predictive losses, we test the null hypothesis that a benchmark model weakly outperforms a collection of competitors uniformly across the conditioning space. The proposed command can implement this test for both independent cross-sectional data and serially dependent time-series data. Confidence sets for the most superior model can be obtained by inverting the test, for which the cspa command also offers a convenient implementation.
在本文中,我们介绍了一种新的命令cspa,它实现了李、廖和Quaedvlieg(2022,经济研究综述89:843–875)开发的条件优越预测能力测试。利用预测方法的条件性能,通过其预测损失的条件期望函数进行非框架测量,我们检验了零假设,即基准模型在条件空间上均匀地弱于竞争对手的集合。所提出的命令可以对独立的横截面数据和序列相关的时间序列数据执行此测试。最高级模型的置信集可以通过反转测试来获得,cspa命令也为其提供了方便的实现。
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引用次数: 0
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