Regression discontinuity design and its applications to Science of Science:A survey

Purpose:With the availability of large-scale scholarly datasets,scientists from various domains hope to understand the underlying mechanisms behind science,forming a vibrant area of inquiry in the emerging“science of science”field.As the results from the science of science often has strong policy implications,understanding the causal relationships between variables becomes prominent.However,the most credible quasi-experimental method among all causal inference methods,and a highly valuable tool in the empirical toolkit,Regression Discontinuity Design(RDD)has not been fully exploited in the field of science of science.In this paper,we provide a systematic survey of the RDD method,and its practical applications in the science of science.Design/methodology/approach:First,we introduce the basic assumptions,mathematical notations,and two types of RDD,i.e.,sharp and fuzzy RDD.Second,we use the Web of Science and the Microsoft Academic Graph datasets to study the evolution and citation patterns of RDD papers.Moreover,we provide a systematic survey of the applications of RDD methodologies in various scientific domains,as well as in the science of science.Finally,we demonstrate a case study to estimate the effect of Head Start Funding Proposals on child mortality.Findings:RDD was almost neglected for 30 years after it was first introduced in 1960.Afterward,scientists used mathematical and economic tools to develop the RDD methodology.After 2010,RDD methods showed strong applications in various domains,including medicine,psychology,political science and environmental science.However,we also notice that the RDD method has not been well developed in science of science research.Research Limitations:This work uses a keyword search to obtain RDD papers,which may neglect some related work.Additionally,our work does not aim to develop rigorous mathematical and technical details of RDD but rather focuses on its intuitions and applications.Practical implications:This work proposes how to use the RDD method in science of science research.Originality/value:This work systematically introduces the RDD,and calls for the awareness of using such a method in the field of science of science.

A Modification to the Fuzzy Regression Discontinuity Model to Settings with Fuzzy Variables

Despite the fact that fuzzy regression discontinuity designs are growing in popularity, a lot of research takes into account treatment non-compliance difficulties, specifically the fuzziness of the treatment impact. This paper took into account independent and dependent fuzzy factors when creating these designs. Additionally we took into account treatment non-compliance difficulties, specifically the fuzziness of the treatment impact, as other research does. The modified Fuzzy Regression Discontinuity model is preferable for modeling fuzzy data. It enables us to draw improved causal effects accommodating fuzzy variables, not just the fuzziness of the treatment effect as in Fuzzy Regression Discontinuity models. A fuzzy dataset is converted into crisp data by the Centroid method of defuzzification. Once the data is crisp, the traditional least squares methods of approximation are used to estimate the parameters in the model since these parameters are considered crisp whilst the error terms are fuzzy. The Alcohol Use Disorders Identification Test score(AUDIT score) can be used as a cutoff to initiate treatment in this case and can be used to predict the progression of HIV disease and/or AIDS. Counseling helps to lower the use of alcohol in people living with HIV/AIDS (PLWHA) as a result, improving the participants’ CD4 counts.

The impact of ESG on financial performance:a revisit with a regression discontinuity approach

This study revisits the question of“whether firms are doing well by doing good?”.We examine shareholders-sponsored corporate socially responsible(CSR)proposals related to Environmental,Social,and Governance(ESG)that are voted to pass or fail by a small margin.The adoption of those“close call”proposals is regarded as equivalent to a random assignment of CSR policies and,therefore,provides a quasi-experimental setting to capture the causal influence of CSR on firm performance.We apply the regression discontinuity design(RDD)and find that CSR proposals’passage leads to a significant positive abnormal return on the voting day.The results are robust with both parametric and nonparametric approaches of RDD and different polynomial orders.However,we fail to identify a significant change in financial performance in the long-term.One possible reason is that passing a CSR proposal could be symbolic,rather than substantial.

Some recent developments in modeling quantile treatment effects

This paper provides a selective review of the recent developments on econometric/statistical modeling in quantile treatment effects under both selection on observables and on unobservables.First,we discuss identification,estimation and inference of quantile treatment effects under the framework of selection on observables.Then,we consider the case where the treatment variable is endogenous or self-selected,for which an instrumental variable method provides a powerful tool to tackle this problem.Finally,some extensions are discussed to the data-rich environments,to the regression discontinuity design,and some other approaches to identify quantile treatment effects are also discussed.In particular,some future research works in this area are addressed.

Can promoting ethanol gasoline usage improve air quality? Evidence from Tianjin, China

Promoting the use of ethanol gasoline is an important approach for China to achieve sustainable and high quality development.Based on the daily air quality data of Tianjin,China,from 2013 to 2020,this paper investigates whether the implementation of the ethanol gasoline policy helped improve air quality using regression discontinuity analysis.We find that the implementation of the ethanol gasoline policy had a very limited positive effect on the overall air quality index(AQI)and no obvious effect on the reduction of particulate matter(PM_(2.5) and PM_(10)).However,the results reveal that the ethanol gasoline policy reduced SO_(2),NO_(2),and CO by about 36%,19%,and 20%,respectively.These findings provide policy insights for other cities in China and other rapidly developing cities in the world to promote the use of ethanol gasoline.

Lifestyle and Time Use: The Impact of Retirement on Health

Based on the data from the China Health and Retirement Longitudinal Study(CHARLS)in 2011 and 2013,this paper studied the impact of retirement on male and female workers’health and its impact mechanism under the mandatory retirement age system in China by using Fuzzy Regression Discontinuity Design(FRDD).The results indicated that retirement increased the probability of men assessing themselves as"healthy"by 25 percentage points and lowered the probability of suffering from chronic diseases for women by 26 percentage points.In terms of mechanism analysis,it was found that the remarkable increase in social interactions after retirement was the main reason for the improvement of health for male retirees,but not the reason for the lower probability of having chronic diseases for female retirees.The findings serve as important references for formulating policies regarding postponing retirement age and flexible retirement.

Responsible Behavior of Irresponsible Companies:Air Pollution and Charitable Donations of Polluting Companies

The relationship between air pollution and charitable donations of companies has received little attention from academia.To make up for this defect,we use a regression discontinuity design based on the spatial discontinuity in air pollution created by China's winter heating policy in the north of Qinling Mountains–Huai River line to examine whether severe air pollution may cause polluting companies to make charitable donations.Our results consistently show that air pollution has a positive impact on the donations of polluting companies,regardless of whether the absolute donations,the relative donations,or the willingness to donate are used to measure donations.A series of robustness tests confirm that this relationship is causal.Furthermore,we find that under severe air pollution,the motivations of polluting companies to implement donation behaviors are to decrease the probability of environmental penalties,reduce environmental pollution costs,and decrease the extent to which air pollution affects company reputations.

Short-Term and Long-Term Margins of International Trade： Evidence from the Canada-Chile Free Trade Agreement

We investigate the impact of the Canada-Chile Free Trade Agreement （CCFTA） on Canadian exports to Chile, particularly the dynamic effects of the agree- ment on extensive and intensive margins of trade. Consistent with the literature, we find that the extensive margin effects occurred later than the intensive margin effects and became more prominent in the long-term. Surprisingly, the intensive margin ef- fects died off in the long-term. A theoretical model is constructed to show that our results can arise in a standard setting of intra-industry trade.

The impact of transfer payments on urban-rural income gap--Based on fuzzy RD analysis of China’s midwestern counties data

In this paper,using 1054 counties data of 15 provinces in Midwestern China from 2000 to 2007,we analyze the impact of transfer payments on urban-rural income gap.By choosing Develop-the-west Strategy that is a quasi-natural experiment and using regression of discontinuity of location,the result shows that local government in western China pays more transfer payments than in the central region,however,the income gap between urban-rural residents in the western region increases by 20%.The widening effects are robust in different bandwidth situation such as distance or latitude and longitude.Meanwhile,the mechanism analyses find that urban residents benefit more than rural residents from transfer payments.Therefore,we believe that transfer payments should be more targeted to invest in rural areas,at the same time,the central government should rationalize the structure of transfer payments as soon as possible,and correct the urban bias and structure bias of local fiscal expenditure.