Ruofan Ma

Hi! I am a PhD candidate in the Department of Government at Harvard University. My research interest lies at the intersection of international institutions, international political economy, and labor politics.

My dissertation project investigates how global governance affects the cross-national implementation of labor rights. I study how international labor institutions, such as the International Labor Organization, drive up domestic labor standards through international monitoring, norm diffusion, and regulatory deference. I also study the cause and effect of international policy diffusion, including sanctions, tariffs, and foreign investments. Methodologically, I have developed novel methods in causal mechanism design and Bayesian networks, which I further apply in my own substantive research. My work leverages a range of research designs and data sources, including natural experiments, administrative data, and archival documents.

I am currently a Graduate Fellow at the Institute for Quantitative Social Science, the Weatherhead Center for International Affairs, and the Asia Center. I received my A.M. degrees in Statistics and Regional Studies East Asia from Harvard University, as well as my Bachelor of Law in Political Science from Peking University.

I'm on the job market during the 2025-26 Academic Year.

1. International Monitoring and Labor Rights: Third Party Participation Deepens Compliance (Job Market Paper). Under Review.
   [Abstract]

   Issuing monitoring reports is one of the key mechanisms through which international organizations provide information to facilitate compliance. Yet, there is great variation in whether such monitoring leads to compliance. This paper argues that a critical design feature that determines this effectiveness is its accessibility to third parties. These actors provide information that allows international organizations to verify states' self-claim of compliance and give more tailored advice on resolving noncompliance. Consequently, reporting processes that allow third-party participation are more likely to affect deeper compliance. To test this argument, I adopt a mixed-method approach under the institutional context of the International Labor Organization (ILO). The ILO sets a wide range of labor standards and adopts various reporting mechanisms to monitor member states' compliance with labor rights. I compare two reporting mechanisms employed by the ILO using difference-in-differences and two-way fixed-effects models. I collect 177 member states' convention-ratification records and ILO reports on their collective labor-rights compliance between 1985 – 2012. ILO reports significantly improve institutional compliance, and reports that involve third-party participation further improve behavioral compliance. Two case studies—Cambodia and China—show that deeper compliance follows from dynamic monitoring in the report-compilation process, where the ILO leverages the reported information to engage international audiences and encourage compliance.
2. BIT by BIT: How Bilateral Investment Treaty Network Shapes Foreign Direct Investment (with Licheng Liu). Under Review.
   [Abstract]

   Do bilateral investment treaties (BITs) have broader effects beyond the signatory states? We posit that the network formed by the collection of BITs transmits information about countries' domestic investment environment, such as the quality of their legal institutions, to other states within the network, which shapes the flow of foreign direct investment (FDI) and facilitates new treaty negotiations. To test this claim, we formalize a novel causal network estimator and tailor its application to a comprehensive dataset of dyadic investment flows between states from 1975 to 2012. We find that when two countries become indirectly connected by BITs through an intermediate country, the FDI flow between the pair increases by an additional 4-6% relative to the unconnected country pairs. Additionally, indirectly connected country pairs become 1-2% more likely to form a new BIT between them. To examine whether the information transmission mechanism facilitates this process, we further investigate heterogeneous treatment effects based on the quality of domestic legal institutions. As country pairs' legal differences widen, treatment effects decrease for FDI flows. Our findings highlight network spillover as a substantial component of the overall effect of BITs: For states within the BIT network, ratifying investment treaties not only strengthens economic ties with its new partner, but also helps transmit investment information to many others.
3. Assumption Smuggling in Intermediate Outcome Tests of Causal Mechanisms (with Matthew Blackwell and Aleksei Opacic). Under Review.
   [Abstract]

   Political scientists are increasingly interested in assessing causal mechanisms, or determining not just if a causal effect exists but also why it occurs. Even so, many researchers avoid formal causal mediation analyses due to their stringent assumptions, instead opting to explore causal mechanisms through what we call intermediate outcome tests. These tests estimate the effect of the treatment on one or more mediators and view such effects as suggestive evidence of a causal mechanism. In this paper, we use nonparametric bounding analysis to show that, without further assumptions, these tests can neither establish nor rule out the existence of a causal mechanism. To use intermediate outcome tests as a falsification test of causal mechanisms, researchers must make a very strong but rarely discussed monotonicity assumption. We develop a way to assess the plausibility of this monotonicity assumption and estimate our bounds for two recent experiments that use these tests.
4. Sanction Spillover and Trade Diversification (with Christina L. Davis). Prepared for submission.
   [Abstract]

   How do sanctions affect third-party states? While much research has focused on the direct impact of sanctions on the countries imposing and receiving them, less is known about their effects on the broader trade network. We propose a theory that states respond to the systemic risks caused by sanctions by diversifying their trade portfolios. We test this theory in two ways: First, we examine how sanctions affect the global trade system, where states learn about trade uncertainty through sanctions on their trading partners. Using trade concentration and sanction data from 1990 to 2020, we find that states diversify their trading partners when sanctions disrupt their networks. Second, we analyze the 2018 announcement by President Trump under Section 232, which imposed unilateral tariffs on steel and aluminum imports based on national security concerns. Through a difference-in-differences approach, we study monthly data on steel and aluminum trade and find that countries with strong trade ties to the U.S. have limited flexibility, while others reduce their reliance on the U.S. by expanding their trade partnerships. These findings highlight the spillover effects of sanctions and the dynamics of trade interdependence.
5. Uncertain Signals: Partisan Cues, Attitudes, and Trade Policy Preferences (with Ethan Miles). Prepared for Submission.
   [Abstract]

   How do individuals evaluate specific trade policies? While a rich literature exists regarding individuals’ perceptions of trade, current research predominantly focuses on abstract attitudes about trade, without assessing the exact mechanisms for how it is expanded or restricted. This project seeks to flesh out the path through which abstract attitudes map into concrete preferences over trade policy and assess the impact of partisan cues on those preferences. We devise two survey experiments that randomizes parties’ stances on a hypothetical US free trade agreement. Evidence from both survey experiments suggests that respondents who receive negative partisan cues—opposition from their own party, or support from their opposing party—have a significantly reduced level of support for the FTA, and are more likely to seek out additional information on trade agreements. In comparison, respondents who receive positive partisan cues demonstrate few behavioral changes. We theorize that instead of serving as information shortcuts, partisan cues on trade policies trigger economic anxiety over the distributive consequences of trade.

1. Domestic Judicialization: Tariffs, Courts, and the Future of International Trade (with Mengyi Wang).
   [Abstract]

   U.S. federal courts are emerging as the new arbiters of international trade, displacing international tribunals. Drawing on two-level game theory, we argue that tariff rulings during the second Trump administration reflect a broader shift in where and how trade policy is judicialized and negotiated. As a result, foreign counterparts have quickly internalized U.S. courts as endogenous constraints in two-level bargaining: escalating retaliation threats, amplifying international complaints with domestic-law arguments, or conditioning any market-access deal on statutory provisions sticky enough to withstand domestic judicial review. Paradoxically, the stabilizing force of domestic rule-of-law—judicial checks on presidential trade power—adds a layer of uncertainty that raises the cost of international cooperation. We conclude by outlining a new research agenda that treats domestic courts as independent veto players shaping credibility, limiting discretion, and restructuring bargaining environments.
2. Multilateral Labor Standards in Bilateral Labor Agreements
3. Adaptation Across International Organizations (with Averell Schmidt).
4. Dynamic Bipartite Stochastic Blockmodel Regression for Network Data: Application to State and Intergovernmental Organization Networks (with Qi Liu, Santiago Olivella, and Kosuke Imai). Poster for 2025 PolMeth