Researchers recently surveyed 18,000 voters in 15 European countries to find out "How Economic, Humanitarian and Religious Concerns Shape European Attitudes Toward Asylum-Seekers." Those interviewed for the study, set for publication Friday in "Science" magazine, evaluated the profiles of 180,000 applicants for asylum, clearly preferring refugees who offered economic benefit to the potential host countries. Stanford University researcher Jens Hainmueller talked to DW about the study's findings - including a heavy bias against Muslim applicants for asylum: Christians were preferred by a margin of 11 percentage points.

DW: What did you set out to find when you undertook the study? What surprised you most about the results?

Jens Hainmueller: How willing are voters to welcome asylum-seekers into their countries? The degree of backlash against governments that are providing protection to the hundreds of thousands of destitute asylum-seekers may obscure variation in attitudes across Western publics. In this light, our study is the first that examines in a systematic manner whether attitudes towards applicants are undifferentiated or dependent on specific characteristics of the applicants. If the latter, the study could help European policy makers to highlight characteristics that their voters embrace in order better to fulfill their obligations in international law and EU regulations. This is important not only for humanitarian reasons, but the continental unity of Europe is also at stake.

Our results from surveying over 18,000 citizens in 15 European countries reveal that public preferences over asylum-seekers are shaped by three main considerations: sociotropic evaluations of their potential economic contributions, humanitarian concerns about the deservingness of their claims and anti-Muslim bias. One surprise was the relative strength of humanitarian considerations in structuring attitudes toward asylum-seekers. Previous research revealed how economic factors are important in guiding voters' preferences on immigrants in general, and so we expected these factors could have similar influence in the asylum context.

Of course, we also expected our respondents would recognize that asylum-seekers are a special type of migrant facing unique struggles, and hence would also take humanitarian concerns into consideration. We did not realize, however, how central this humanitarian impulse would be, with our results showing a level of importance placed on humanitarian concerns that was comparable with that given to economic factors. So when it comes to asylum-seekers, the findings suggest that the European public has at least partially internalized the central pillars of international refugee law: Many citizens agree that asylum-seekers who face persecution, have consistent asylum testimonies and have special vulnerabilities deserve protection. These preferences are widely shared across countries and apply across all types of asylum-seekers, regardless of their religion and employability.

How did the results vary by nation? Were there countries that were particularly hostile to the idea of refugees? Countries where the division was particularly strong on religious grounds?

Asylum preferences followed a similar pattern across the 15 surveyed countries, despite the fact that these countries exhibit major differences with regard to several potentially relevant factors for shaping asylum preferences, such as the number of asylum applications per capita, the existence of an EU external border or their economic strength. Similarly, attitudes toward asylum-seekers are fairly similar across respondents of different age, education, income and political ideology.

There were two partial exceptions to this European consensus. First, the magnitude of the anti-Muslim bias varies somewhat. Anti-Muslim bias is much stronger among those who place themselves on the right of the left-right political spectrum. Second, the penalty against asylum-seekers who migrate for economic reasons is somewhat smaller in poorer countries (e.g. ,Czech Republic, Greece, Hungary, Poland) compared to richer countries (e.g., Austria, Denmark, Germany, Netherlands, Norway, Sweden, and Switzerland).

What political and social challenges does the study suggest for policy makers? More importantly, what might it mean for refugees?

This public consensus on what types of asylum-seekers to accept has important implications for policy. The results illuminate both challenges and opportunities for policymakers who are struggling to meet their legal responsibilities to protect refugees while simultaneously respecting the public will on this salient and divisive issue. While the results suggest that the principles enshrined in international refugee law play an important role in structuring asylum attitudes, we do not find public opinion to be in absolute lock step with international legal norms.

The fact that our respondents exhibited anti-Muslim bias and a preference for higher employability - even when evaluating legally legitimate asylum-seekers who face persecution - is at odds with the legal requirements that asylum not be given on the basis of religion or professional skills. Of course, we cannot expect that public opinion, as complex and multifaceted as it is, would perfectly mirror international legal ideals, but the public's strong anti-Muslim bias and preference for highly skilled asylum-seekers who can speak the language of the host country points to a mounting challenge for solving the current crisis and successfully integrating asylum-seekers, given that most asylum-seekers currently originate from Muslim-majority countries and may lack the desired professional and language skills. Yet at the same time, the fact that the European public shares common humanitarian and sociotropic concerns suggests a clear narrative to increase support for accepting refugees. If the goal is to alleviate the social tensions of the current refugee crisis and generate more public acceptance of asylum-seekers, European policy makers have an opportunity to highlight refugees' deservingness and vulnerability as well as their economic contributions to their host societies.

You have previously done research on borders and border issues. What personal interest did you have in this study? What sort of political impact would you like for it to have?

Immigration produces some of the most urgent and fundamental challenges of our time, but often policy makers and advocacy groups get so focused on ideological debates that they seemingly forget to evaluate which polices and programs are actually effective. Our interdisciplinary research team at the Immigration Policy Lab is committed to careful evaluation that should inform public debate. The Lab - partnering with community-based organizations, local, state and federal governments - supervises numerous studies to quantify the societal and economic impacts of various immigration and integration policies in Europe and North America. The important and largely unanswered research question that our lab examines is this: What can governments and communities actually do to effectively facilitate the integration of immigrants and unlock the many benefits that immigration can bring to host countries?

You have previously worked in Germany. Are there aspects of the study that are especially applicable here? How do the results compare with your experiences here?

Our study suggests that public attitudes towards asylum-seekers in Germany are not too different from public attitudes towards asylum-seekers in many other European countries, even though Germany has obviously taken on a much larger responsibility in the current crisis while other countries have closed their borders. Taking in many refugees provides tremendous challenges, but also tremendous opportunities for the country.

Policy makers face an urgent challenge to promote the integration of refugees into the German economy and society through better policies. The German economy is strong, and refugees can help make it even stronger: They bring new ideas, skills, perseverance - and they take risks. But German authorities, especially at the local but also at the federal level, need policies informed by careful research to unlock the economic potential of refugees, and realizing these gains will not happen overnight.

Last year my parents decided to come back from retirement to work as teachers for a class of refugees who have arrived in Freiburg. They work tirelessly with the refugees to help them learn the language, find jobs and navigate the bureaucracy. Efforts like these are sorely needed and can make a big difference to enable refugees to make a contribution to Germany.

Jens Hainmueller is a professor at Stanford and the faculty co-director of the university's Immigration Policy Lab.