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Articles 481 - 510 of 1733
Full-Text Articles in Economics
Illusion Of Gender Parity In Education: Intrahousehold Resource Allocation In Bangladesh, Sijia Xu, Abu S. Shonchoy, Tomoki Fujii
Illusion Of Gender Parity In Education: Intrahousehold Resource Allocation In Bangladesh, Sijia Xu, Abu S. Shonchoy, Tomoki Fujii
Research Collection School Of Economics
A target in the Millennium Development Goals—gender parity in all levels of education—is widely considered to have been attained. However, measuring gender parity only through school enrollment is misleading, as girls may lag behind boys in other educational measures. We investigate this with four rounds of surveys from Bangladesh by decomposing households’ education decisions into enrollment, education expenditure, and share of the education expenditure allocated for the quality of education like private tutoring. We find a strong profemale bias in school enrollment but promale bias in the other two decisions. This contradirectional gender bias is unique to Bangladesh and partly …
Robustly Optimal Reserve Price, Wei He, Jiangtao Li
Robustly Optimal Reserve Price, Wei He, Jiangtao Li
Research Collection School Of Economics
We study a robust version of the single-unit auction problem. The auctioneer has confidence in her estimate of the marginal distribution of a generic bidder's valuation, but does not have reliable information about the joint distribution. In this setting, we analyze the performance of second-price auctions with reserve prices in terms of revenue guarantee, that is, the greatest lower bound of revenue across all joint distributions that are consistent with the marginals. For any finite number of bidders, we solve for the robustly optimal reserve price that generates the highest revenue guarantee. Our analysis has interesting implications in large markets. …
Weak Σ-Convergence: Theory And Applications, Jianning Kong, Peter C. B. Phillips, Donggyu Sul
Weak Σ-Convergence: Theory And Applications, Jianning Kong, Peter C. B. Phillips, Donggyu Sul
Research Collection School Of Economics
The concept of relative convergence, which requires the ratio of two time series to converge to unity in the long run, explains convergent behavior when series share commonly divergent stochastic or deterministic trend components. Relative convergence of this type does not necessarily hold when series share common time decay patterns measured by evaporating rather than divergent trend behavior. To capture convergent behavior in panel data that do not involve stochastic or divergent deterministic trends, we introduce the notion of weak σ-convergence, whereby cross section variation in the panel decreases over time. The paper formalizes this concept and proposes a simple-to-implement …
Inference In Partially Identified Panel Data Models With Interactive Fixed Effects, Shengjie Hong, Liangjun Su, Yaqi Wang
Inference In Partially Identified Panel Data Models With Interactive Fixed Effects, Shengjie Hong, Liangjun Su, Yaqi Wang
Research Collection School Of Economics
This paper develops methods for statistical inferences in a partially identified nonparametric panel data model with endogeneity and interactive fixed effects. We consider the case where the number of cross-sectional units (N) is large and the number of time series periods (T).as well as the number of unobserved common factors (R) are fixed. Under some normalization rules, wecan concentrateout thelarge dimen-sional parameter vector of factor loadings and specify a set of conditional moment restriction that are involved with only the finite dimensional factor parameters along with the infinite dimensional nonpara-metric component. For a conjectured restriction on the parameter, we consider …
M-Estimators Of U-Processes With A Change-Point Due To A Covariate Threshold, Lili Tan, Yichong Zhang
M-Estimators Of U-Processes With A Change-Point Due To A Covariate Threshold, Lili Tan, Yichong Zhang
Research Collection School Of Economics
Economic theory often predicts a “tipping point” effect due to multiple equilibria. Linear threshold regressions estimate the “tipping point” by assuming at the same time that the response variable is linear in an index of covariates. However, economic theory rarely imposes a specific functional form, but rather predicts a monotonic relationship between the response variable and the index. We propose new, rank-based, estimators for both the “tipping point” and other regression coefficients, exploiting only the monotonicity condition. We derive the asymptotic properties of these estimators by establishing a more general result for M-estimators of U-processes with a change-point due to …
Optimal Social Insurance With Informal Child Care, Christine Ho
Optimal Social Insurance With Informal Child Care, Christine Ho
Research Collection School Of Economics
The possibility of engaging in household child care may exacerbate the incentives of parents and grandparents to falsely claim disability benefits as households also get to save on formal child care costs. This paper considers a multi-generational family model with persistence in privately observed shocks and presents an efficient implementation case for subsidizing formal child care costs of the disabled. An implementation of the optimal scheme that consists of capped formal day care subsidies, non-linear income taxation and asset-testing is proposed. Simulations based on a parametrization that targets key features of the US labor and child care markets suggest that …
Maximum Likelihood Estimation For The Fractional Vasicek Model, Katsuto Tanaka, Weilin Xiao, Jun Yu
Maximum Likelihood Estimation For The Fractional Vasicek Model, Katsuto Tanaka, Weilin Xiao, Jun Yu
Research Collection School Of Economics
This paper is concerned about the problem of estimating the drift parameters in the fractional Vasicek model from a continuous record of observations. Based on the Girsanov theorem for the fractional Brownian motion, the maximum likelihood (ML) method is used. The asymptotic theory for the ML estimates (MLE) is established in the stationary case, the explosive case, and the null recurrent case for the entire range of the Hurst parameter, providing a complete treatment of asymptotic analysis. It is shown that changing the sign of the persistence parameter will change the asymptotic theory for the MLE, including the rate of …
Forecasting Equity Index Volatility By Measuring The Linkage Among Component Stocks, Yue Qiu, Tian Xie, Jun Yu, Qiankun Zhou
Forecasting Equity Index Volatility By Measuring The Linkage Among Component Stocks, Yue Qiu, Tian Xie, Jun Yu, Qiankun Zhou
Research Collection School Of Economics
The linkage among the realized volatilities across component stocks are important when modeling and forecasting the relevant index volatility. In this paper, the linkage is measured via an extended Common Correlated Effects (CCE) approach under a panel heterogeneous autoregression model where unobserved common factors in errors are assumed. Consistency of the CCE estimator is obtained. The common factors are extracted using the principal component analysis. Empirical studies show that realized volatility models exploiting the linkage effects lead to significantly better out-of-sample forecast performance, for example, an up to 32% increase in the pseudo R2. We also conduct various forecasting exercises …
Limit Theory For Moderate Deviations From Integrated Garch Processes, Yubo Tao
Limit Theory For Moderate Deviations From Integrated Garch Processes, Yubo Tao
Research Collection School Of Economics
This paper develops the limit theory of the GARCH(1,1) process that moderately deviates from IGARCH process towards both stationary and explosive regimes. The asymptotic theory extends Berkes et al. (2005) by allowing the parameters to have a slower rate of convergence. The results can be applied to unit root test for processes with mildly-integrated GARCH innovations (e.g. Boswijk (2001), Cavaliere and Taylor (2007, 2009)) and deriving limit theory of estimators for models involving mildly-integrated GARCH processes (e.g. Jensen and Rahbek (2004), Francq and Zakoïan (2012, 2013).
Central Place Theory And The Power Law For Cities, Wen-Tai Hsu, Zou Xin
Central Place Theory And The Power Law For Cities, Wen-Tai Hsu, Zou Xin
Research Collection School Of Economics
This chapter provides a review of the link between central place theory and the power laws for cities. A theory of city size distribution is proposed via a central place hierarchy a la Christaller (1933) either as an equilibrium results or an optimal allocation. Under a central place hierarchy, it is shown that a power law for cities emerges if the underlying heterogeneity in economies of scale across good is regularly varying. Furthermore, we show that an optimal allocation of cities conforms with a central place hierarchy if the underlying heterogeneity in economies of scale across good is a power …
Actuarial Modeling And Analysis Of The Hong Kong Life Annuity Scheme, Koon Shing Kwong, Wai-Sum Chan, Johnny Siu-Hang Li
Actuarial Modeling And Analysis Of The Hong Kong Life Annuity Scheme, Koon Shing Kwong, Wai-Sum Chan, Johnny Siu-Hang Li
Research Collection School Of Economics
The Hong Kong Mortgage Corporation (HKMC) Limited, which was established in March 1997 and is wholly owned by the government of the Hong Kong Special Administrative Region, has a major mission to develop and provide different financial retirement instruments to Hong Kong residents to help address the income poverty of retirees. In June 2017, HKMC Annuity Limited, a wholly-owned subsidiary of the HKMC was incorporated to implement a new life annuity scheme which would be launched by mid-2018 to cater for the needs of cash-rich Hong Kong old age residents. The objective of the scheme is to provide an additional …
Does Foreign Direct Investment Lead To Industrial Agglomeration?, Wen-Tai Hsu, Yi Lu, Xuan Luo, Lianming Zhu
Does Foreign Direct Investment Lead To Industrial Agglomeration?, Wen-Tai Hsu, Yi Lu, Xuan Luo, Lianming Zhu
Research Collection School Of Economics
This paper studies the effect of foreign direct investment (FDI) on industrial agglomeration.Using the differential effects of FDI deregulation in 2002 in China on different industries, we find that FDI actually affects industrial agglomeration negatively. This result is somewhat counter-intuitive, as the conventional wisdom tends to suggest that FDI attracts domestic firms to cluster for various agglomeration benefits, in particular technology spillovers. To reconcile our empirical findings and the conventional wisdom, we develop a theory of FDI and agglomeration based on two counter-veiling forces. Technology diffusion from FDI attracts domestic firms to cluster, but fiercer competition drives firms away. Which …
Social Policy Reform And Rigidity In Singapore's Authoritarian Developmental State, Lily Zubaidah Rahim, Lam Keong Yeoh
Social Policy Reform And Rigidity In Singapore's Authoritarian Developmental State, Lily Zubaidah Rahim, Lam Keong Yeoh
Research Collection School Of Economics
Singapore’s economic achievements have been widely applauded as a model worthy of emulation, particularly by authoritarian and rapidly industrialising economies. Yet, the city-state retains the dubious distinction of being one of the most inequitable countries in the world—in income inequality terms. Singapore is the only developed economy where workers are not entitled to a minimum wage or compulsory retrenchment benefits. However, following the 2011 electoral backlash against the long-serving People’s Action Party (PAP) government, numerous social policy reforms were introduced. But have these social policy reforms been effective in qualitatively addressing income and socio-economic inequality? To address this question, the …
Regional Prevalence Of Health Worker Absenteeism In Tanzania, Tomoki Fujii
Regional Prevalence Of Health Worker Absenteeism In Tanzania, Tomoki Fujii
Research Collection School Of Economics
Absenteeism of health workers in developing countries is common and can severely undermine the reliability of the health system. Therefore, it is important to understand where the prevalence of absenteeism is high. We develop a simple imputation method that combines a Service Delivery Indicators survey and a Service Provision Assessment survey to estimate the prevalence of absenteeism of health workers at the level of regions in Tanzania. The resulting estimates allow one to identify the regions in which the prevalence of absenteeism is significantly higher or lower than the national average and help policymakers determine priority areas for intervention.
Refusal Bias In Hiv Data From The Demographic And Health Surveys: Evaluation, Critique And Recommendations, Oyelola A. Adegboye, Tomoki Fujii, Denis H. Y. Leung
Refusal Bias In Hiv Data From The Demographic And Health Surveys: Evaluation, Critique And Recommendations, Oyelola A. Adegboye, Tomoki Fujii, Denis H. Y. Leung
Research Collection School Of Economics
Non-response is a commonly encountered problem in many population-based surveys. Broadly speaking, non-response can be due to refusal or failure to contact the sample units. Although both types of non-response may lead to bias, there is much evidence to indicate that it is much easier to reduce the proportion of non-contacts than to do the same with refusals. In this article, we use data collected from a nationally-representative survey under the Demographic and Health Surveys program to study non-response due to refusals to HIV testing in Malawi. We review existing estimation methods and propose novel approaches to the estimation of …
Efficient Estimation Of Integrated Volatility Functionals Via Multi-Scale Jackknife, Jia Li, Yunxiao Liu, Dacheng. Xiu
Efficient Estimation Of Integrated Volatility Functionals Via Multi-Scale Jackknife, Jia Li, Yunxiao Liu, Dacheng. Xiu
Research Collection School Of Economics
We propose semiparametrically efficient estimators for general integrated volatility functionals of multivariate semimartingale processes. A plug-in method that uses nonparametric estimates of spot volatilities is known to induce high-order biases that need to be corrected to obey a central limit theorem. Such bias terms arise from boundary effects, the diffusive and jump movements of stochastic volatility and the sampling error from the nonparametric spot volatility estimation. We propose a novel jackknife method for bias correction. The jackknife estimator is simply formed as a linear combination of a few uncorrected estimators associated with different local window sizes used in the estimation …
Asymptotic Theory For Estimating Drift Parameters In The Fractional Vasicek Model, Weilin Xiao, Jun Yu
Asymptotic Theory For Estimating Drift Parameters In The Fractional Vasicek Model, Weilin Xiao, Jun Yu
Research Collection School Of Economics
This article develops an asymptotic theory for estimators of two parameters in the drift function in the fractional Vasicek model when a continuous record of observations is available. The fractional Vasicek model with long-range dependence is assumed to be driven by a fractional Brownian motion with the Hurst parameter greater than or equal to one half. It is shown that, when the Hurst parameter is known, the asymptotic theory for the persistence parameter depends critically on its sign, corresponding asymptotically to the stationary case, the explosive case, and the null recurrent case. In all three cases, the least squares method …
A Two-Round In-Class Trading Game On The Principle Of Comparative Advantage And The Theory Of Reciprocal Demand, Bei Hong
Research Collection School Of Economics
This paper outlines a classroom trading game that explores equilibrium terms of trade using the principle of comparative advantage and theory of reciprocal demand. Students are divided into eight groups. Each group is assigned a country with hypothetical productivity and each country seeks its trading partner based on comparative advantage. Students simulate the trading of goods between countries with the objective of achieving the best possible terms of trade. The game encourages students to reflect on their learning of the principle of comparative advantage, consider improvements in trade terms through negotiation, and summarize the conditions for mutually beneficial terms of …
Nonstationary Panel Models With Latent Group Structures And Cross-Section Dependence, Wenxin Huang, Sainan Jin, Peter C. B. Phillips, Liangjun Su
Nonstationary Panel Models With Latent Group Structures And Cross-Section Dependence, Wenxin Huang, Sainan Jin, Peter C. B. Phillips, Liangjun Su
Research Collection School Of Economics
This paper proposes a novel Lasso-based approach to handle unobserved parameter heterogeneity and cross-section dependence in nonstationary panel models. In particular, a penalized principal component (PPC) method is developed to estimate group-specific long-run relationships and unobserved common factors and jointly to identify the unknown group membership. The PPC estimators are shown to be consistent under weakly dependent innovation processes. But they suffer an asymptotically non-negligible bias from correlations between the nonstationary regressors and unobserved stationary common factors and/or the equation errors. To remedy these shortcomings we provide three bias-correction procedures under which the estimators are re-centered about zero as both …
Competition, Markups, And Gains From Trade: A Quantitative Analysis Of China Between 1995 And 2004, Wen-Tai Hsu, Yi Lu, Guiying Laura Wu
Competition, Markups, And Gains From Trade: A Quantitative Analysis Of China Between 1995 And 2004, Wen-Tai Hsu, Yi Lu, Guiying Laura Wu
Research Collection School Of Economics
This paper provides a quantitative analysis of gains from trade in a model with head-to-head competition using Chinese firm-level data from Economic Censuses in 1995 and 2004. We find a significant reduction in trade cost during this period, and total gains from such improved openness during this period is 7:1%. The gains are decomposed into a Ricardian component and two pro-competitive ones. The procompetitive effects account for 20% of the total gains. Moreover, the total gains from trade are 13 31% larger than what would result from the formula provided by ACR (Arkolakis, Costinot, and Rodríguez-Clare 2012), which nests a …
On Factor Models With Random Missing: Em Estimation, Inference, And Cross Validation, Liangjun Su, Ke Miao, Sainan Jin
On Factor Models With Random Missing: Em Estimation, Inference, And Cross Validation, Liangjun Su, Ke Miao, Sainan Jin
Research Collection School Of Economics
We consider the estimation and inference in approximate factor models with random missing values. We show that with the low rank structure of the common component, we can estimate the factors and factor loadings consistently with the missing values replaced by zeros. We establish the asymptotic distributions of the resulting estimators and those based on the EM algorithm. We also propose a cross validation-based method to determine the number of factors in factor models with or without missing values and justify its consistency. Simulations demonstrate that our cross validation method is robust to fat tails in the error distribution and …
Made In Singapore, Pao-Li Chang, Phuong T. B. Nguyen
Made In Singapore, Pao-Li Chang, Phuong T. B. Nguyen
Research Collection School Of Economics
In this paper, we characterize the position of Singapore in global value chains and identify Singapore's key upstream and downstream trade partners. We trace how the position of Singapore in global value chains has changed in the past two decades: whether it has moved upstream or downstream, how involved it is in global value chains, how its trend compares with other major Asian exporting countries (China, Japan, Korea and Taiwan), and which key sectors of Singapore play a major role in these global trade networks.
Monthly Spending Dynamics Of The Elderly Following A Health Shock: Evidence From Singapore, Terence C. Cheng, Jing Li, Rhema Vaithianathan
Monthly Spending Dynamics Of The Elderly Following A Health Shock: Evidence From Singapore, Terence C. Cheng, Jing Li, Rhema Vaithianathan
Research Collection School Of Economics
We use novel longitudinal data from 19 monthly waves of the Singapore Life Panel to examine the short-term dynamics of the effects health shocks have on household health and non-health spending and income by the elderly. The health shocks we study are the occurrence of new major conditions such as cancer, heart problems, and minor conditions (e.g. diabetes, and hypertension). Our empirical strategy exploits unanticipated changes in health status through the diagnosis of new health conditions, combined with an individual fixed effect framework. We find that major shocks have large and persistent effects while minor shocks have small and mainly …
Financial Sector In Singapore, Hwee Kwan Chow, Sai Fan Pei
Financial Sector In Singapore, Hwee Kwan Chow, Sai Fan Pei
Research Collection School Of Economics
This chapter reviews the financial development strategies adopted by the Singapore government as it navigates internal and external changes to build a vibrant center of finance in the Asia Pacific region. Sections 2 and 3 provide an overview of the structure of the financial system and the financial governance framework respectively. This is followed by a discussion, in Section 4, on the outward looking development strategy that underpinned the successful development of Singapore’s financial sector. Section 5 highlights the reforms undertaken in the aftermath of the Asian financial crisis that led to the building of a well-diversified and thriving international …
Specification Tests For Temporal Heterogeneity In Spatial Panel Models With Fixed Effects, Yuhong Xu, Zhenlin Yang
Specification Tests For Temporal Heterogeneity In Spatial Panel Models With Fixed Effects, Yuhong Xu, Zhenlin Yang
Research Collection School Of Economics
We propose score type tests for testing the existence of temporal heterogeneity in slope and spatial parameters in spatial panel data (SPD) models, allowing for the presence of individual-specific and/or time-specific fixed effects (or in general intercept heterogeneity). The SPD model with spatial lag effect is treated in detail by first considering the model with individual-specific effects only, and then extending it to the model with both individual and time specific effects. Two types of tests (naive and robust) are proposed, and their asymptotic properties are presented. These tests are then fully extended to an SPD model with both spatial …
Econometric Estimates Of Earth's Transient Climate Sensitivity, Peter C. B. Phillips, Thomas Leirvik, Trude Storelvmo
Econometric Estimates Of Earth's Transient Climate Sensitivity, Peter C. B. Phillips, Thomas Leirvik, Trude Storelvmo
Research Collection School Of Economics
How sensitive is Earth's climate to a given increase in atmospheric greenhouse gas (GHG) concentrations? This long-standing question in climate science was recently analyzed by dynamic panel data methods using extensive spatio-temporal data of global surface temperatures, solar radiation, and GHG concentrations over the last half century to 2010 (Storelvmo et al, 2016). Those methods revealed that atmospheric aerosol effects masked approximately one-third of the continental warming due to increasing GHG concentrations over this period, thereby implying greater climate sensitivity to GHGs than previously thought. The present study provides regularity conditions and asymptotic theory justifying the use of time series …
Semiparametric Maximum Likelihood Inference For Nonignorable Nonresponse With Callbacks, Zhong Guan, Denis H. Y. Leung, Jing Qin
Semiparametric Maximum Likelihood Inference For Nonignorable Nonresponse With Callbacks, Zhong Guan, Denis H. Y. Leung, Jing Qin
Research Collection School Of Economics
We model the nonresponse probabilities as logistic functions ofthe outcome variable and other covariates in the survey sampling study withcallback. The identification aspect of this callback model is investigated. Semiparametricmaximum likelihood estimators of the parameters in the responseprobabilities are proposed and studied. As a result, an efficient estimator ofthe mean of the outcome variable is constructed using the estimated responseprobabilities. Moreover, if a regression model for conditional mean of the outcomevariable given some covariate is available, then we can obtain an evenmore efficient estimate of the mean of the outcome variable by fitting the regressionmodel using an adjusted least squares …
Mild-Explosive And Local-To-Mild-Explosive Autoregressions With Serially Correlated Errors, Yiu Lim Lui, Weilin Xiao, Jun Yu
Mild-Explosive And Local-To-Mild-Explosive Autoregressions With Serially Correlated Errors, Yiu Lim Lui, Weilin Xiao, Jun Yu
Research Collection School Of Economics
This paper firstly extends the results of Phillips and Magdalinos (2007a) by allowing for anti-persistent errors in mildly explosive autoregressive models. It is shown that the Cauchy asymptotic theory remains valid for the least squares (LS) estimator. The paper then extends the results of Phillips, Magdalinos and Giraitis (2010) by allowing for serially correlated errors of various forms in local-to-mild-explosive autoregressive models. It is shown that the result of smooth transition in the limit theory between local-to-unity and mild-explosiveness remains valid for the LS estimator. Finally, the limit theory for autoregression with intercept is developed.
Coarse Revealed Preference, Gaoji Hu, Jiangtao Li, John K. Quah, Rui Tang
Coarse Revealed Preference, Gaoji Hu, Jiangtao Li, John K. Quah, Rui Tang
Research Collection School Of Economics
We identify necessary and sufficient conditions under which a coarse data set canbe coarsely rationalized by a linear order (or weak order). The conditions are easy tocheck, and efficient algorithms are provided. We apply our theory to investigate theobservable restrictions of several economic models including (1) rational choice withimperfect observation; (2) multiple preferences; (3) monotone multiple preferences; and(4) minimax regret.
Root-N Consistency Of Intercept Estimators In A Binary Response Model Under Tail Restrictions, Lili Tan, Yichong Zhang
Root-N Consistency Of Intercept Estimators In A Binary Response Model Under Tail Restrictions, Lili Tan, Yichong Zhang
Research Collection School Of Economics
The intercept of the binary response model is irregularly identified when the supports of both the special regressor V and the error term ε are the whole real line. This leads to the estimator of the intercept having potentially a slower than √n convergence rate, which can result in a large estimation error in practice. This paper imposes addition tail restrictions which guarantee the regular identification of the intercept and thus the √n-consistency of its estimator. We then propose an estimator that achieves the √n rate. Finally, we extend our tail restrictions to a full-blown model with endogenous regressors.