Jens Hainmueller

Stanford University | SU · Department of Political Science and Graduate School of Business

Given the global displacement crisis, the integration of refugees has emerged as a critical policy issue for many host countries. A key challenge involves supporting refugees in learning the language of their host country. While several European nations have instituted publicly funded language training for asylum seekers and refugees soon after the...

Protracted global conflicts during the past decade have led to repeated major humanitarian protection crises in Europe. During the height of the Syrian refugee crisis at the end of 2015, Europe hosted around 2.3 million people requesting asylum¹. Today, the ongoing war in Ukraine has resulted in one of the largest humanitarian emergencies in Europe...

European governments, struggling with the incorporation of diverse immigrant populations, introduced integration contracts. Through language training and compulsory civics courses, the goal is to induce immigrants to adopt host society culture and respect its values. Despite their popularity, little empirical evidence exists whether they catalyze i...

Political scientists have increasingly deployed conjoint survey experiments to understand multidimensional choices in various settings. In this paper, we show that the average marginal component effect (AMCE) constitutes an aggregation of individual-level preferences that is meaningful both theoretically and empirically. First, extending previous r...

A critical barrier to generating cumulative knowledge in political science and related disciplines is the inability of researchers to observe the results from the full set of research designs that scholars have conceptualized, implemented, and analyzed. For a variety of reasons, studies that produce null findings are especially likely to be unobser...

We develop a real-time scalable method to analyze strategic communication by political actors on salient policy issues through their tweets. Using word embeddings and supervised machine learning models, we classify legislators' tweets according to whether or not they reference policy issues as well as what positions they promote. This allows us to...

Experimental political science has changed. In two short decades, it evolved from an emergent method to an accepted method to a primary method. The challenge now is to ensure that experimentalists design sound studies and implement them in ways that illuminate cause and effect. Ethical boundaries must also be respected, results interpreted in a tra...

We introduce a constrained priority mechanism that combines outcome-based matching from machine learning with preference-based allocation schemes common in market design. Using real-world data, we illustrate how our mechanism could be applied to the assignment of refugee families to host country locations, and kindergarteners to schools. Our mechan...

This cohort study explores whether an inclusive, local health care system could serve as a buffer against adverse effects on access to health care due to actions related to immigration status in patients who are likely undocumented.

We present a method to conduct automated surveys over WhatsApp, a popular cross-platform messaging service. The method relies on a combination of the WhatsApp Business API as well as the Twilio and Google platforms to design the survey flow, send and receive survey messages automatically, and facilitate data processing. Respondents complete the sur...

Immigration legal services providers (ISPs) are a principal source of support for low-income immigrants seeking immigration benefits. Yet there is scant quantitative evidence on the prevalence and geographic distribution of ISPs in the United States. To fill this gap, we construct a comprehensive, nationwide database of 2,138 geocoded ISP offices t...

At a time of heightened anxiety surrounding immigration, state governments have increasingly sought to manage immigrant and refugee flows. Yet the factors that influence where immigrants choose to settle after arrival remain unclear. We bring evidence to this question by analyzing population-level data for refugees resettled within the United State...

A growing number of countries have established programs to attract immigrants who can contribute to their economy. Research suggests that an immigrant's initial arrival location plays a key role in shaping their economic success. Yet immigrants currently lack access to personalized information that would help them identify optimal destinations. Ins...

Conjoint experiments are popular, but there is a paucity of research on respondents’ underlying decision-making processes. We leverage eye-tracking methodology and a series of conjoint experiments, administered to university students and local community members, to examine how respondents process information in conjoint surveys. There are two main...

With international migration at a record high, a burgeoning literature has explored the drivers of public attitudes toward migrants. However, most studies to date have focused on developed countries, which have relatively fewer migrants and more capacity to absorb them. We address this sample bias by conducting a survey of public attitudes toward S...

A critical barrier to generating cumulative knowledge in political science and related disciplines is the inability of researchers to observe the results from the full set of research designs that scholars have conceptualized, implemented, and analyzed. For a variety of reasons, studies that produce null findings are especially likely to be unobser...

We provide evidence that citizenship catalyzes the long-term economic integration of immigrants. Despite the relevance of citizenship policy to immigrant integration, we lack a reliable understanding of the economic consequences of acquiring citizenship. To overcome nonrandom selection into naturalization, we exploit the quasi-random assignment of...

Importance Federal policy changes in 2002 and 2009 led some states to expand public health insurance coverage to non–US-born children and pregnant women who are lawful permanent residents during their first 5 years of residency in the United States. In other states, there were concerns that insurance expansion could attract immigrants to relocate t...

Available at: https://ssrn.com/abstract=2715746 What explains the sharp divide among European publics over the Grexit? We explore this question using original surveys from four of the largest European economies. We contend that differences in citizens' own economic interests, as well as the often-mentioned chasm between supporters of mainstream an...

Citizenship can accelerate immigrant integration and result in benefits for both local communities and the foreign-born themselves. Yet the majority of naturalization-eligible immigrants in the United States do not apply for citizenship, and we lack systematic evidence on policies specifically designed to encourage take-up. In this study, we analyz...

There is widespread concern in Europe and other refugee-receiving continents that living in an enclave of coethnics hinders refugees’ economic and social integration. Several European governments have adopted policies to geographically disperse refugees. While many theoretical arguments and descriptive studies analyze the impact of spatially concen...

We show that an information nudge increased the rate of American citizenship applications among low-income immigrants eligible for a federal fee waiver. Approximately half of the 9 million naturalization-eligible immigrants qualify for a federal programme that waives the cost of the citizenship application for low-income individuals. However, take-...

Do minorities fare worse under direct democracy than under representative democracy? We provide new evidence by studying naturalization requests of immigrants in Switzerland that were typically decided with referendums in each municipality. Using panel data from about 1,400 municipalities for the 1991–2009 period, we exploit Federal Court rulings t...

Recent years have seen a renaissance of conjoint survey designs within social science. To date, however, researchers have lacked guidance on how many attributes they can include within conjoint profiles before survey satisficing leads to unacceptable declines in response quality. This paper addresses that question using pre-registered, two-stage ex...

Citizenship can accelerate immigrant integration and result in benefits for both local communities and the foreign-born themselves. Yet, naturalization rates in the United States are lower than in other traditional immigration countries and we lack evidence on which policies are effective in raising them. In this study, we analyze the impact of a m...

How Much Should We Trust Estimates from Multiplicative Interaction Models? Simple Tools to Improve Empirical Practice – CORRIGENDUM - Jens Hainmueller, Jonathan Mummolo, Yiqing Xu

Facilitating the integration of refugees has become a major policy challenge in many host countries in the context of the global displacement crisis. One of the first policy decisions host countries make in the resettlement process is the assignment of refugees to locations within the country. We develop a mechanism to match refugees to locations i...

We provide evidence that citizenship catalyzes the long-term economic integration of immigrants. Despite the relevance of citizenship policy to immigrant integration, we lack a reliable understanding of the economic consequences of acquiring citizenship. To overcome non-random selection into naturalization, we exploit the quasi-random assignment of...

Objectives To determine whether expanding Emergency Medicaid to cover prenatal care in Oregon affected maternal health outcomes for unauthorized immigrants. Methods This study takes place in Oregon from 2003 to 2015 and includes all Emergency Medicaid and Medicaid claims for women aged 12-51 with a pregnancy related claim. To isolate the effect of...

Conjoint experiments are popular, but there is a paucity of research on respondents' underlying decision-making processes. We leverage eye-Tracking methodology and a series of conjoint experiments, administered to university students and local community members, to examine how respondents process information in conjoint surveys. There are two main...

Multiplicative interaction models are widely used in social science to examine whether the relationship between an outcome and an independent variable changes with a moderating variable. Current empirical practice tends to overlook two important problems. First, these models assume a linear interaction effect that changes at a constant rate with th...

The successful integration of immigrants into a host country’s society, economy, and polity has become a major issue for policymakers in recent decades. Scientific progress in the study of immigrant integration has been hampered by the lack of a common measure of integration, which would allow for the accumulation of knowledge through comparison ac...

Many European countries impose employment bans that prevent asylum seekers from entering the local labor market for a certain waiting period upon arrival. We provide evidence on the long-term effects of these employment bans on the subsequent economic integration of refugees. We leverage a natural experiment in Germany, where a court ruling prompte...

Significance Despite the scale of the US refugee resettlement program, policymakers and the public lack systematic information on how refugees adapt to their new environment. We focus on naturalization as a key measure of integration and draw on administrative data to provide direct estimates of the naturalization rates among refugees. Our results...

In recent years, political and social scientists have made increasing use of conjoint survey designs to study decision-making. Here, we study a consequential question which researchers confront when implementing conjoint designs: How many choice tasks can respondents perform before survey satisficing degrades response quality? To answer the questio...

Data-driven refugee assignment The continuing refugee crisis has made it necessary for governments to find ways to resettle individuals and families in host communities. Bansak et al. used a machine learning approach to develop an algorithm for geographically placing refugees to optimize their overall employment rate. The authors developed and test...

Citizenship endows legal protections and is associated with economic and social gains for immigrants and their communities. In the United States, however, naturalization rates are relatively low. Yet we lack reliable knowledge as to what constrains immigrants from applying. Drawing on data from a public/private naturalization program in New York, t...

Food retailers and manufacturers are increasingly committing to address agricultural sustainability issues in their supply chains. In place of using established eco-certifications, many companies define their own supply chain sustainability standards. Scholars remain divided on whether we should expect such company-led programs to affect change. We...

Objective: To measure the effect of access to prenatal care on unauthorized and low-income, new legal permanent resident immigrant women and their offspring. Methods: We used a difference-in-differences design that leverages the staggered rollout of Emergency Medicaid Plus by county from 2008 to 2013 as a natural experiment to estimate the effec...

Life under threat of deportation What is the effect on a child of having parents who are at risk of deportation as unauthorized immigrants? Hainmueller et al. developed a quasi-experimental protocol to address this complicated question. They selected mothers who had birthdates either just before or just after the cutoff for the United States' Defer...

The Stata package krls as well as the R package KRLS implement kernel-based regularized least squares (KRLS), a machine learning method described in Hainmueller and Hazlett (2014) that allows users to tackle regression and classification problems without strong functional form assumptions or a specification search. The flexible KRLS estimator learn...

What type of common asylum regime would Europeans support? We conducted a survey asking 18,000 citizens of 15 European countries about their preferences regarding different mechanisms for allocating asylum seekers across countries. A large majority supports an allocation that is proportional to each country’s capacity over the status quo policy of...

Financial bailouts for ailing Eurozone countries face deep and widespread opposition among voters in donor countries, casting major doubts over the political feasibility of further assistance efforts. What is the nature of the opposition and under what conditions can governments obtain broader political support for funding such large-scale, interna...

Significance Several states have experimented with more inclusive policies toward immigrants. There is little empirical evidence related to their impact. Our study examines the short-term traffic safety effects of one of the largest-scale state policies focused on the integration of unauthorized immigrants: California’s extension of driving privile...

In recent years, political and social scientists have made increasing use of conjoint survey designs to study decision-making. Here, we study a consequential question which researchers confront when implementing conjoint designs: how many choice tasks can respondents perform before survey satisficing degrades response quality? To answer the questio...

Many European countries impose employment bans that prevent asylum seekers from entering the local labor market for a certain waiting period upon arrival. We provide evidence on the long-term effects of such employment bans on the subsequent economic integration of refugees. We leverage a natural experiment in Germany, where a court ruling prompted...

A consensus in Europe about asylum seekers Violent conflicts between groups often generate large numbers of noncombatant refugees. Bansak et al. surveyed western European attitudes toward such asylum seekers. They found that voters favor applicants who will contribute to the recipient country's economy, who have suffered severe physical or mental d...

European governments are struggling with the biggest refugee crisis since World War II, but there exists little evidence regarding how the management of the asylum process affects the subsequent integration of refugees in the host country. We provide new causal evidence about how one central policy parameter, the length of time that refugees wait i...

This study tests the hypothesis that lean manufacturing improves the social performance of manufacturers in emerging markets. We analyze an intervention by Nike, Inc., to promote the adoption of lean manufacturing in its apparel supply chain across 11 developing countries. Using difference-in-differences estimates from a panel of more than 300 fact...

We study the impact of naturalization on the long-term social integration of immigrants into the host country society. Despite ongoing debates about citizenship policy, we lack reliable evidence that isolates the causal effect of naturalization from the non-random selection into naturalization. We exploit the quasi-random assignment of citizenship...

What explains the sharp divide among European publics over the Grexit? We explore this question using original surveys from four of the largest European economies. We contend that differences in citizens' own economic interests, as well as the often-mentioned chasm between supporters of mainstream and extremist parties, provide little insight into...

Multiplicative interaction models are widely used in social science to test whether the relationship between an outcome and an independent variable changes with a moderating variable. Current empirical practice overlooks two important problems. First, these models assume a linear interaction effect that changes at a constant rate with the moderator...

The caseworker-to-clients ratio is an important, but understudied, policy parameter that a_ects both the quality and cost of public employment services that help job seekers _nd employment. We exploit a large-scale pilot by Germany's employment agency that hired 490 additional caseworkers in 14 of its 779 offices. We find that lowering caseloads ca...

Significance The political integration of immigrant minorities is one of the most pressing policy issues many countries face today. Despite heated debates, there exists little rigorous evidence about whether naturalization fosters or dampens the integration of immigrants into the political fabric of the host society. Our study provides new causal e...

The regression discontinuity (RD) design is popular because it provides a design-based estimate of the incumbency advantage. However, the RD estimate is "local": It only identifies the effect in hypothetical elections with a 50-50 tie between the Democratic and Republican candidates. There is significant uncertainty and disagreement over the incumb...

We provide new evidence on consumer demand for ethical products from experiments conducted in a U.S. grocery store chain.We find that sales of the two most popular coffees rose by almost 10% when they carried a Fair Trade label as compared to a generic placebo label. Demand for the higher-priced coffee remained steady when its price was raised by 8...

Significance Little evidence exists on whether preferences about hypothetical choices measured in a survey experiment are driven by the same structural determinants of the actual choices made in the real world. This study answers this question using a natural experiment as a behavioral benchmark. Comparing the results from conjoint and vignette exp...

A large literature argues that public opinion is vulnerable to various types of framing and cue effects. However, we lack evidence on whether existing findings, which are typically based on lab experiments involving low-salience issues, travel to salient and contentious political issues in real-world voting situations. We examine the relative impor...

We study the impact of naturalization on the long-term social integration of immigrants into the host country society. Despite ongoing debates about citizenship policy, we lack reliable evidence that isolates the causal effect of naturalization from the non-random selection into naturalization. We exploit the quasi-random assignment of citizenship...

Immigrant populations in many developed democracies have grown rapidly, and so too has an extensive literature on natives’ attitudes toward immigration. This research has developed from two theoretical foundations, one grounded in political economy, the other in political psychology. These two literatures have developed largely in isolation from on...

Why do voters agree to bear the costs of bailing out other countries? Despite the prominence of public opinion in the ongoing debate over the eurozone bailouts, voters' preferences on the topic are poorly understood. We conduct the first systematic analysis of this issue using observational and experimental survey data from Germany, the country sho...

The electoral regression discontinuity (RD) design is popular because it provides an unbiased, design-based estimate of the incumbency advantage with few assumptions. However, as is well known, the RD estimate is "local": it only identifies the effect in hypothetical districts with an exactly 50-50 tie between the Democratic and Republican candidat...

The political integration of immigrant minorities is one of the most pressing policy issues many countries face today. Despite heated debates, there exists little rigorous evidence about whether naturalization fosters or dampens the integration of immigrants into the political fabric of the host society. Our study provides new causal evidence on th...

The Stata package ebalance implements entropy balancing, a multivariate reweighting method described in Hainmueller (2012 ) that allows users to reweight a dataset such that the covariate distributions in the reweighted data satisfy a set of specified moment conditions. This can be useful to create balanced samples in observational studies with a b...

Many papers use regression discontinuity (RD) designs that exploit "close" election outcomes in order to identify the effects of election results on various political and economic outcomes of interest. Several recent papers critique the use of RD designs based on close elections because of the potential for imbalance near the threshold that disting...

We propose the use of Kernel Regularized Least Squares (KRLS) for social science modeling and inference problems. KRLS borrows from machine learning methods designed to solve regression and classification problems without relying on linearity or additivity assumptions. The method constructs a flexible hypothesis space that uses kernels as radial ba...

We propose the use of Kernel Regularized Least Squares (KRLS) for social science modeling and inference problems. KRLS borrows from machine learning methods designed to solve regression and classification problems without relying on linearity or additivity assumptions. The method constructs a flexible hypothesis space that uses kernels as radial ba...