Historical Subsistence Strategies and Culture

The link between the climate and culture has been examined in a variety of contexts.  A recent post by Volha Charnysh discusses various examples, such as the relationship between seasonality and the adoption of agriculture (Matranga, 2019), climatic risk and cooperation (Buggle and Durante, 2021), and exposure to adverse natural shocks and religiosity (Bentzen, 2019). In this post I explore the related hypothesis of how the particular demands of historical subsistence strategies shape cultural outcomes and how this persists overtime. I focus on the growing literature on the effects of pastoralism, which is the reliance on animal herding for economic production and norms associated with a culture of honor, violence, restrictive gender norms, and trust.

A Culture of Honor

A well-known hypothesis is that pastoralist societies facilitated the development of a “culture of honor” (Nisbett and Cohen, 1996). In culture of honor societies, people, particularly men, feel obligated to protect their reputation by responding to insults or threats with violence and a willingness to take revenge. A reliance on animal herding may have shaped this particular bundle of cultural traits because herders constantly face a constant of others trying to steal their animals and tend to live in areas with minimal state presence. Thus, their reputation – particularly for violence and willingness to defend themselves and their herd – is an important deterrent.

Cattle, Goats, and Sheep with Three Herdsmen, one Drinking. 1654. (Nicolaas Pietersz Berchem, 1620-1683)

Pauline Grosjean (2014) empirically examines the hypothesis that a culture of honor leads to higher levels of violence in the context of the US South. In the 18th century, much of the US South was settled by Scots-Irish, herders from the Scottish Highlands. These areas were historically reliant on pastoralism and were known for high levels of lawlessness and violence. Pauline establishes a relationship between greater Scots-Irish presence and higher homicide rates in the South. Strikingly, a one percentage point increase in the share of Scots-Irish in the 1790 population is associated with a 25 percent higher homicide rate among white offenders. She suggests that this culture of honor was particularly persistent in the South, relative to the North of the US, because formal institutions remained weaker in the South, and thus the culture of honor continued to provide benefits.

Cao et al. (2020) provide broader evidence that societies that historically relied on herding activities do indeed exhibit a bundle of cultural traits associated with a culture of honor. They first examine conflict levels by matching data from the ethnographic atlas (Murdock, 1967), which has measures of historical reliance on pastoralism, with data on conflict outcomes between 1989 and 2016 from the Uppsala Conflict Data Program. They find a significant relationship between historical reliance on herding and contemporary conflict.

They then turn to the psychological and cultural factors that may support a culture of honor, such as negative reciprocity. Negative reciprocity is the willingness to punish someone who has treated others unfairly and to take revenge. Using data from the Global Preferences Survey (Falk et al. 2018), which has survey based measures of negative reciprocity, the authors find that reliance on herding is associated with greater willingness to punish others or take revenge.

Pro-longed Male Absence and Restrictive Gender Norms

Anke Becker (2019) provides evidence that historical reliance on herding affects gender norms. In pastoralist societies, men tend to be in charge of managing the herds and can be away from the home for extended periods of time. Because paternal certainty tends to be much lower than maternal certainty and investment in children is costly, pro-longed male absence may have led to the development of cultural norms that are designed to constrain women’s sexuality. Specifically, it may lead to greater use of female genital cutting and norms that prohibit women’s sexuality and mobility.

Note: This is from Becker (2019), Figure 1.

Using data from Murdock (1967) to construct a measure of reliance on animal husbandry combined with data from Demographic and Health Surveys, she finds that greater reliance on pastoralism leads to higher rates of the most extreme form of female genital cutting. Additionally, women from pastoralists groups are more likely to believe that women should wait until marriage to have sex and support norms that restrict women’s mobility – e.g. that the husband should provide permission for the wife to visit family or that domestic violence is acceptable if a woman leaves the house without telling her husband.

Mobile Pastoralism and In-Group Trust

In recent work, Etienne Le Rossignol and I (2021) explore how historical reliance on mobile pastoralism has shaped in-group relative to out-group trust. Mobile pastoralism is characterized by reliance on raising livestock in highly difficult environments, mobile settlement patterns, and threats to the animals from pests or raids from other groups.  Anthropologists had suggested that the demands of mobile pastoralism may have led tosar higher levels of in-group trust and cooperation. In their ethnographic study in Africa among pastoralists and farmers, Edgerton (1971) conclude that pastoral groups are “more independent-minded in their behavior” and “display more cohesiveness despite their greater independence of actions” than nearby farmer groups.

We modify Becker’s (2019) measure of reliance on pastoralism to account for a group’s mobility. Using data from the World Values Survey and the European Values Survey, we examine how mobile pastoralism has affected levels of trust in the in-group (e.g. family members, neighbors, other people known by respondent) relative to the out-group (i.e. people you meet for the first time, people of another religion, foreigners). We find a positive and significant relationship between reliance on pastoralism and in-group trust bias (greater in-group relative to out group trust). This pattern holds across countries, within countries, among second generation migrants, and using an IV strategy.

We also examine the economic implications of greater in-group trust bias for firm growth. Recent work on firm size has suggested that limited managerial capacity and reliance on family members to run firms may be a constraint on the development of larger firms. We find evidence in favor of this hypothesis; firms in countries with greater historical reliance on pastoralism tend to be smaller and rely on less objective criteria for promotion.

These papers all provide evidence on how the specific requirements of subsistence strategies – in this case, pastoralism – have shaped culture. They also suggest that these traits can be highly persistent, even among second generation migrants, and that they have important implications for violence, firm growth, and the well-being of women. The studies raise the interesting question of under what circumstances these cultural traits are more likely to persist.

Big and Small Gods

Religious and supernatural beliefs are nearly universal across societies. While the belief systems vary in their specific tenets, they range from belief systems that include a moralizing high God to much more decentralized belief systems that feature ancestors, witchcraft, and sorcery. Understanding the origins and effects of these various belief systems for individual and group level outcomes is of great interest in many disciplines, including increasingly in economics. I highlight a few papers in this space that explore the effects of these different religious and supernatural belief systems.

Big Gods and Cooperative Behavior

A compelling hypothesis is that monotheistic religions with moralizing high Gods – e.g. “Big God” religions like Christianity and Islam – help increase cooperation in a society (Norenzayan, 2013). Moralizing high Gods, through their ability to monitor behavior and punish those who behave badly, may have allowed for the transition from small tight-knit societies to large scale societies. Norenzayan et al. (2016) develop a cultural evolutionary model to illustrate how so-called pro-social religions can increase cooperation with co-religionists, and in the context of intergroup competition, make a group more successful. The potential downsides of this are highlighted by Skali (2017), who finds that greater belief in moralizing Gods is associated with greater conflict prevalence and causalities in Africa. He suggests that this is evidence that moralizing Gods help solve collective action problems, such as organizing to engage in intergroup conflict.

Religion, Insurance, and Risk Taking

Aside from the effects at a societal level, belief in moralizing Gods may also affect individual behavior. For example, Auriol et al. (2020) explore how religious institutions may serve as a form of insurance in the context of a Pentecostal church in Accra, Ghana. The authors randomize access to formal insurance policies to examine how access to formal insurance affects giving in a dictator game with the church, with a secular charity, and with a national-wide prayer event. The authors find that enrollment in formal insurance reduces giving in a dictator game with the church and with other recipients relative to individuals who just receive information on the insurance. The authors interpret the finding that giving to all recipients is reduced as consistent with a view that participants believe God provides insurance in response to good behavior. This is contrast to an alternative potential mechanism in which participants are less in need of access to community and Church resources once they receive formal insurance.

In a related paper, Auriol et al. (2021) examine how religious beliefs affect individual risk-taking behavior in Haiti. Participants in a lab experiment completed a series of lotteries. They are given the choice of paying to play the lotteries in the presence of a religious image (Catholic, Protestant or Vodoo). Those who choose to pay for an image take more risks in the lotteries, consistent with the individuals believing in an interventionist God who will improve their chances of winning.

Small Gods, Witchcraft, and Sorcery

While monotheistic religions tend to be the focus of much research on the effects of religion, there are many other diverse belief systems that include ancestors, witchcraft and sorcery. Often, these are characterized by amoral supernatural agents, in contrast to moralizing Big Gods. The effects of these other belief systems are relatively underexplored in economics. An exception is work by Gershman (2016), who examines the relationship between belief in witchcraft and trust in sub-Saharan Africa. He establishes a strong correlation between regional belief in witchcraft and lower levels of generalized trust. Interestingly, an individual’s personal belief in witchcraft is not predictive of generalized trust levels. See the figure below for a map of witchcraft belief and trust.

Notes. Panels (a) and (b) show the regional prevalence of generalized trust and witchcraft beliefs, respectively, based on aggregated survey responses. The breakdown into tencategories corresponds to deciles of the relevant distribution. Black and gray lines reflect national and regional boundaries, respectively.

In a subsequent paper, Gershman (2020) explores one potential explanation for prevalence of belief in witchcraft: exposure to the Atlantic slave trade. He finds that within sub-Saharan Africa greater exposure to the slave trade is associated with greater belief in witchcraft. He also finds that individuals Afro-descendants in Latin America are more likely to believe in witchcraft as are people in places that had a greater historical reliance on slave labor.

While I only highlight several papers here, there is a lot of exciting research in this area. For those who are interested, I recommend following ASREC, which regularly hosts conferences on culture and religion in economics.

Social Structures and Development

While in many Western societies kinship systems are no longer important in our everyday lives, this has not been the case historically, nor is it presently the case for many parts of the developing world. There has been growing interest in understanding how variation in social structures such as kinship systems shape a wide variety of outcomes, including individual psychology, conflict, and the well-being of women.

Kinship Systems and the Western Church

In a recent Science article, Schulz et al. (2019) explore the effects of the Western Church’s (what would eventually become the Roman Catholic Church) efforts to undermine kinship systems in Europe. The authors note that kinship systems are a primary social structure for most of the world’s societies. They determine residence, marriage patterns, alliance formation, and norms. These kin-based institutions have had important consequences for individual psychology, encouraging cooperation and in-group loyalty, at the expense of individualism and impersonal fairness and cooperation.

The Romanesque portal of the church Our-Lady in Avy, Charente-Maritime, France

The authors are interested in understanding how the Western Church’s ban on cousin marriage and related policies of marriage by choice and requiring neo-local residence affected the intensity of kin-based institutions and subsequent psychology. They find that globally, countries with longer exposure to the Western Church are more individualistic and more cooperative with strangers. Examining variation within countries in Europe, they find similar patterns. Finally, they also examine adult children of immigrants in European countries and find that greater intensity of exposure to the Western Church of the parents’ home countries is associated with more individualistic behavior and greater fairness and trust in strangers. The authors’ findings suggest that some of the so-called WEIRD – Western, Educated, Industrialized, Rich, and Democratic – psychology is a product of the policies pursued by the Church to undermine kin-based institutions.

Segmentary Lineages and Conflict

One form of organizing kinship is through segmentary lineages. Segmentary lineage societies are characterized by unilineal descent (tracing group membership through either the male or female line) and the presence of subsets of a full lineage that have political functions. Anthropologists had hypothesized that this form of social organization may lead to more conflict because it facilitates the mobilization of men to fight when there is a conflict. When there is conflict between various segments of a lineage, those within that segment and related segments are obligated to mobilize on behalf of those involved in the conflict. A Bedouin proverb illustrates the logic: “I against my brothers; my brothers and I against my cousins; my cousins, my brothers, and I against the world”. See the figure below for an illustration of various lineage segments.

This hypothesis is explored in Moscona, Nunn, and Robinson (2020) for sub-Saharan Africa. They code various ethnic groups as belonging to segmentary lineage societies or not. They pair this data geo-coded data on conflict. They find that there is a positive and significant relationship between practicing segmentary lineage and greater incidence of conflict, duration of conflict, and number of fatalities. The result is present across all types of conflicts (e.g. civil conflict, within-group conflicts). They find evidence that the effects of segmentary lineage on conflict are particularly strong for retaliatory conflicts – which suggests that segmentary lineages may facilitate the escalation of small disputes to larger-scale conflicts.

Matrilineal Kinship and the Well-Being of Women

Another form of variation in kinship structure is whether lineage and descent are traced through male or female members. In matrilineal systems, group membership is determined through women, rather than through men as in patrilineal systems. This may have important implications for the well-being of women and children. Anthropologists had highlighted how matrilineal systems may both empower women but undermine spousal cooperation. This is due to particular features of matrilineal systems. First, in matrilineal systems husbands and wives have so-called split allegiances, as they each retain strong ties with their own kin group. Women retain stronger ties with their family members, since their children are part of their kin group, and men are responsible for providing for their sisters’ children. Second, husbands have less authority over their wives, as the wife can more easily leave a spouse to return to her kin group. See the figure below for a comparison of matrilineal relative to patrilineal kinship.

In Lowes (2018), I explore the implications of matrilineal kinship relative to patrilineal kinship for spousal cooperation and the well-being of women and children. I examine this in the context of the matrilineal belt, which describes the distribution of matrilineal kinship systems across the center of Africa. I take two strategies to explore this question. First, I collect survey and experimental data from couples living in a town near the matrilineal belt border in the Democratic Republic of Congo (DRC). Couples participate in a public goods game where they are paired with a spouse or with a stranger of the opposite sex. I find that matrilineal individuals are less cooperative with their spouse when there is plausible deniability about the initial size of their endowment in the game. I do not find an equivalent effect for when spouses are paired with strangers of the opposite sex. These results are consistent with matrilineal systems leading to less spousal cooperation.

Second, I examine outcomes related to investment in children and women’s empowerment. I use the survey data from my sample in DRC as well as data from the Demographic and Health Surveys for countries along the matrilineal belt. I find that children of matrilineal women are healthier and better educated in both my sample and in the DHS. I also find that women are less likely to have experienced domestic violence and are less supportive of domestic violence. These results suggest matrilineal systems improve outcomes for women and children.

Conclusion

The papers discussed are just a few examples of the growing literature connecting variation in development outcomes to social structures. Other work, such as Enke (2019), explores how kinship tightness affects cooperation and moral systems (note, the map at the top of this post is from this paper). The papers tie social organization to variation in cooperation at various scales and highlight the importance of understanding how social structures shape incentives for cooperation.

Works Cited

Enke, Ben. “Kinship, Cooperation, and the Evolution of Moral Systems.” Quarterly Journal of Economics, 2019, vol. 134(2), pp. 953-1019.

Lowes, Sara. “Matrilineal Kinship and Spousal Cooperation: Evidence from the Matrilineal Belt”. 2018.

Moscana, Jacob, Nathan Nunn, and James A. Robinson. “Segmentary Lineage Organization and Conflict in Sub-Saharan Africa.” Econometrica. Volume 88. Number 5. September 2020, 1999-2036.

Schulz, Jonathan F., Duman Bahrami-Rad, Jonathan P. Beauchamp, and Joseph Henrich. “The Church, intensive kinship and global psychological variation.” Science. Volume 366. Number 707. November 2019.

 

Colonial Era Concessions and Present Day Development

During the colonial era, colonial powers granted concessions to private companies across Africa, Asia, and Latin America. These concessions varied in the scope of their  coercive powers, the type of natural resource being extracted, and the various investments (or lack there of) that were made in the local economy and people.

A growing literature is piecing together how the various characteristics of these concession companies continues to shape the economies of countries today.

The Mita in Peru

An influential paper in this literature is work by Melissa Dell on the effects of the mining mitain Peru (Dell, 2010). While not technically a concession to a private company, the paper explores how a system of forced labor instituted by the Spanish government over the course of several centuries affects present day development in Peru. During the mita era, individuals inside the boundaries of a particular region were required to send one-seventh of their adult male population to work in silver and mercury mines. Despite that the mitawas abolished in 1812, Dell finds that areas that were subjected to forced labor experience worse development outcomes today. Households have lower consumption and children have greater levels of childhood stunting.

To understand why the effects of the mitapersist, the author focuses on the development of haciendas – estates primarily devoted to agriculture with an attached labor force. These estates tended to develop outside of the mitaarea to avoid having their work force subjected to the forced labor requirements. The haciendasalso tended to provide public goods, such as investment in the road network. Thus, areas inside the mitacatchment area did not benefit from this provision of public goods. This work both highlighted how historical economic arrangements can shape present day development, and it suggested a particular channel – subsequent investments by other economic agents – for why negative effects persist.

The Dutch Cultivation System in Java

In a closely related paper, Dell and Olken (2020) examine how the coercive cultivation system set up by the Dutch in Java continues to affect economic production today. Between the 1830s to the 1870s, the Dutch forced peasants to cultivate sugar, which was then processed in nearby sugar plants. Prior to the cultivation system, local production was primarily focused on rice. Thus, to implement the cultivation system required a reorganization of the local economy. Ninety-four sugar factories were built, and villages in nearby catchment areas were forced to grow sugar cane (see figure at the top of the post). The authors find that households near former factories are much more likely to be engaged in manufacturing relative to agriculture, have higher per-capita consumption, and are more connected to related industries. Relatedly, areas close to the sugar factories are also more integrated into the road network. The paper suggests that exposure to this forced cultivation system had a deep impact on how the economy was organized, and that the investments made by the Dutch shaped economic production long after the end of the cultivation system.

The Congo Free State

In much of sub-Saharan Africa, colonizing powers granted concessions to private companies that were characterized by extraction of natural resources (e.g. rubber), the use of violence, and the co-option of local leaders. Within Africa, concessions existed in French, British, Belgian, German, and Portuguese colonies (e.g. Angola, Botswana, Central African Republic, Cameroon, Chad, DRC, Gabon, Malawi, Mozambique, Namibia, Nigeria, Republic of Congo, Tanzania, Zambia, Zimbabwe). One of the most extreme examples of the concession system was in the Congo Free State, where King Leopold II of Belgium granted concessions to private companies to extract rubber. Lowes and Montero (2020) examine the legacy of two of these concessions – Abir and Anversoise, which existed from 1982 to 1906. They find that areas that were part of the former concessions experience worse development outcomes today: they have lower levels of education, wealth and health than equivalent areas just outside of the former concessions.

To understand why these short lived concessions continue to negatively affect present day development, the authors collected survey and experimental data from individuals who come from inside and outside of the former concession boundaries. First, they examine the effects on local institutions. During the concession era, chiefs were required to cooperate with the concession companies and enforce rubber quotas, or they would be replaced and possibly killed by the concession company agents. Consistent with co-option of local chiefs undermining the quality of local institutions, the authors find that chiefs inside the former concessions provide fewer public goods and are less likely to be elected. Second, they examine how the exposure to the violent concession system shaped pro-social preferences. Perhaps surprisingly, the authors find evidence that greater exposure to the concessions is associated with more pro-social norms. Individuals from inside the former concession are more trusting and more supportive of sharing and redistribution. This is possibly due to the fact that local institutions were undermined, forcing individuals to rely on each other for survival. The study suggests that this coercive form of economic production that was highly prevalent across sub-Saharan Africa both continues to affect present day development and that it has had a long run negative effect on the efficacy of local institutions.

The United Fruit Company in Costa Rica

Recent work by Mendez-Chacon and van Patten (2020) explores the legacy of the United Fruit Company in Costa Rica. The United Fruit Company (UFC) was one of the largest multinationals of the 20th century. The firm was given concessions across Central America, including in Costa Rica, for the production of bananas. In contrast with Lowes and Montero (2020) and Dell (2010), the authors find that individuals living inside the UFC boundary are better off on a wide variety of development outcomes, including housing, sanitation, education and consumption. The authors are able to trace this effect to two related channels. First, the UFC invested in amenities for workers in the area, including the provision of schools and hospitals. The authors hypothesize that this incentive for investment was closely tied to the mobility of local workers: in order to keep the work force on the banana plantation, the workers required particular amenities or they would leave. Thus, greater worker mobility induced greater investment on the part of the UFC.

Concessions to Private Companies

Taken as a whole, these studies provide evidence on how concessions to private firms may shape subsequent development outcomes. In cases where firms had incentive to invest in either capital or human capital, the negative effects are attenuated (e.g. in Java or Costa Rica). In cases where extreme violence and coercion could be used – such as in the Congo Free State – the negative effects of these concessions continue to be felt. The studies highlight how the various features of the concession companies – e.g. type of product being extracted or produced, the constraints put on the company, the investments made in the local economy, and the mobility of workers – affect the long run legacy of these concessions.

References

Dell, Melissa, “The Persistent Effects of Peru’s Mining Mita,” Econometrica, 2010, 78 (6), 1863– 1903.

Dell, Melissa and Benjamin A. Olken, “The Development Effects of the Extractive Colonial Economy: The Dutch Cultivation System in Java,” The Review of Economic Studies, 2020, 87 (1), 164–203.

Lowes, Sara and Eduardo Montero, “Concessions, Violence, and Indirect Rule: Evidence from the Congo Free State,” December 2020.

Méndez-Chacón, Esteban and Diana Van Patten, “Multinationals, Monopsony, and Local Development,” July 2020.

Trust in Medicine

As the United States prepares to undertake one of the largest vaccination efforts in its history – the photo above shows an earlier such effort, the polio vaccination of the mid-to-late 1950s – approximately 60 percent of Americans report in a recent PEW survey that they are likely or very likely to take up a COVID vaccine.

In a survey of individuals from 19 countries on their willingness to be vaccinated, 71.5 percent of participants indicated they would be willing to be vaccinated – with much cross-country variation, ranging from 90 percent in China to less than 55 percent in Russia.

Thus, there is a large gap between those who are willing to be vaccinated and the target of 90 percent coverage for herd immunity recently suggested by Dr. Fauci. This large gap amidst a global pandemic highlights the importance of understanding the determinants of trust in medicine and willingness to be vaccinated. Recent work in economics has begun to explore how historical experiences shape trust in medicine and vaccination rates.

Sleeping Sickness Campaigns in Central Africa

In a paper with Eduardo Montero, we study the case of sleeping sickness campaigns undertaken by the French military in Cameroon and former French Equatorial Africa (present day Central African Republic, Chad, Republic of Congo, and Gabon). Between the 1920s and the 1950s, the French colonial governments organized extensive medical campaigns aimed at managing sleeping sickness, a lethal disease spread by the tsetse fly. Over the course of several decades, millions of individuals were forcibly injected with medications intended to either treat or prevent sleeping sickness. These medications were of dubious efficacy and has serious side effects, including blindness, gangrene infections, and death.

We digitize colonial records of campaign exposure for thirty years and match this data with present day information on vaccination rates for children and willingness to consent to a free and non-invasive blood test for HIV or anemia, which we interpret as a revealed preference measure of trust in medicine. Our results suggest that greater exposure to these historical medical campaigns characterized by lack of consent and use of harmful medications has led to lower trust in medicine. Those places with more exposure to the campaigns have lower vaccination rates for children and respondents are less likely to consent to the free blood test for HIV or anemia.

Nurse drawing blood in Cameroon.

The Tuskegee Study

Related work in the United States by Marcella Alsan and Marianne Wanamaker examines the legacy of the Tuskegee Study. Between the 1932 and 1972, hundreds of black men who were known to have syphilis were monitored by doctors to study the course of disease, despite the availability of effective treatment. In 1972, news of the study, its deception of participants, and the withholding of treatment for syphilis became public.

Alsan and Wanamaker examine how black men respond to the revelation of the study. They find that black men report greater mistrust in medicine and suffer from higher mortality. They are also less likely to interact with physicians. The authors estimate that the revelation of the Tuskegee study led to a decrease in life expectancy for black men of approximately 1.5 years – or 35 percent of the racial gap in life expectancy in 1980.

Blood is drawn from a Tuskegee study subject. (National Archives)

The CIA and Immunization in Pakistan

Monica Martinez-Bravo and Andreas Stegmann examine how a vaccine ruse organized by the CIA has affected immunization rates in Pakistan. In 2011, the CIA organized a vaccination campaign as a cover for their effort to find Osama Bin Laden. The goal of the vaccination campaign was to collect DNA samples from children living in what was suspected to be Bin Laden’s compound. Two months after the capture of Bin Laden, an article describing the vaccination ruse and the collaboration of a Pakistani doctor was published in the Guardian.

Martinez-Bravo and Stegmann find large decreases in vaccinations – particularly in those areas under the control of the Taliban where individuals where more likely to have been exposed to anti-vaccine propaganda campaigns.

A Pakistani health worker administers polio vaccine drops to a child in Quetta. (Getty)

Rebuilding Trust?

Together, these papers highlight the importance of historical experiences in shaping trust in medicine. They demonstrate how medical malpractice – either in the form of withholding treatment or forcibly treating individuals – and the use of vaccination campaigns for political purposes can lead to substantive and long-lasting negative effects in vaccination compliance and health outcomes. As the COVID pandemic has made particularly clear, rebuilding trust in medicine will be crucial to achieving effective vaccination coverage.

In an effort to understand how to improve health outcomes for black men, the group most affected by the Tuskegee study, Marcella Alsan, Owen Garrick, and Grant Graziani designed a study in which they randomly assign black men to have a black male doctor or a non-black male doctor. They examine how the identity of the doctor affects willingness to take up preventive health services, such as diabetes screening, cholesterol screening, and the flu shot. They find that black men are more likely to take up these preventative health services when they are paired with a black doctor. They find evidence that patients perceive that doctors of their own racial background were more likely to understand their health concerns.

These results suggest the importance of doctor identity in health care provision, as well as highlight one avenue for rebuilding trust in medicine among groups affected by historical medical malpractice.