Macartan Humphreys
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Conflict data from East Congo
2014 "Crowdseeding Conflict Data" (Preprint, Forthcoming Journal of Conflict Resolution) | data and more   (with P van der Windt). We set up a pilot SMS based system for documenting conflict events in East Congo in real time. In a short period the system produced tremenduosly rich data from otherwise inaccessible areas. While we document the usefulness of this type of finegrained real time data we also lament the fact that humanitarian actors on the ground have shown little interest in making use of it.

Process Tracing & Qualitative Research
2014 "Mixing Methods" (Preprint)   (with A Jacobs). In which we describe a Bayesian approach for integrating inferences from qualitative and quantitative research.

Persuasion
2014 "The Elements of Political Persuasion: Content, Charisma, and Cue" (Preprint)   (Economic Journal) (with T Dewan and D Rubenson). In which we find evidence for a strong campaign effects during a referendum in British Columbia. Both message-based and endorsement-based campaigns seemed to work but we find a surprisingly muted role for idiosyncratic features of prospective persuaders. (Replication and other material)

Not lying with statistics
2013 "Fishing, Commitment, and Communication" (Preprint)   (Political Analysis) (with P van der Windt and R Sanchez de la Sierra). Even though everyone knows it is wrong, it is common practice in empirical social science to select what results to report only after analysing data. This practice of "data fishing" can result in enormous bias and an unreliable body of published research. We argue here that it is time to put a stop to this practice by introducing norms for research registration in political science. We describe the scope for bias under weak registration systems and discuss likely effects of registration on the sort of research that gets produced and reported. (replication material)

See also:
2014: Promoting Transparency in Social Science Work (Science) (with E Miguel and others)
2013: Monkey Business (Reprinted in the APSA Comparative Politics Newsletter)

Impacts of Development Aid (Again)
2012 "Democratic Institutions and Collective Action Capacity"   (with J Fearon and J Weinstein) (Working paper). Results from a field experiment with behavioral measures in Liberia to try to work out the effects of community driven development interventions on cooperation. We find overall positive effects but strong heterogeneity suggesting that the effect of these interventions depends strongly on the nature of collective action problems facing communities.

Gerrymandering
2011 "Can compactness constrain the gerrymander?" (preprint) (gated copy). Irish Political Studies. also in Hard Questions for Democracy (2012))   Gerrymandering produces oddly shaped constituencies that result in electoral outcomes that are unrepresentative of population preferences. This note shows that no shape constraints can prevent gerrymandering and indeed odd shapes may be required to ensure minimal representativeness; this clarifies that the problem of representativeness follows from two party first past the post system, not from the shape of constituencies.

Causal Inference:
"Bounds on least squares estimates of causal effects in the presence of heterogeneous assignment probabilities "
The way most quantitative researchers "control" for confounding factors actually produces biased estimates of average causal effects if causal effects are different for different units. I provide a condition to work out when these biases might not be too severe.

Metrics and Majority Rule:
2010 "Spatial Models, Cognitive Metrics and Majority Rule Equilibria" (with M Laver) British Journal of Political Science. [Replication files (R) for Table 1 and Figure 3]
A tragedy of majority rule is that in general when you have complex policy choices to make you will find that for any proposed outcome there will always be some majority that would prefer something else. We show that there might be a solution to this problem if people calculate political distances by simply adding up differences across multiple dimensions of policy.

Ethnic politics:
2009 Coethnicity: Diversity and the Dilemmas of Collective Action   (with J Habyarimana, D Posner and J Weinstein)   New York: Russell Sage Press | Chapter 1 | Buy at Amazon
In this book we try to work out why diverse groups often have problems working together. We analyze data from a suite of experiments that we ran in Kampala, Uganda, and find that in that context at least the problem doesn't seem to lie in fundamental incompatibilities but rather with the strategies that have been adopted to regulate within group behavior.

Impacts of Development Aid:
2009 "Can Development Aid Contribute to Social Cohesion After Civil War? Evidence from a Field Experiment in Post-Conflict Liberia"   (with J Fearon and J Weinstein)   American Economic Review (replication data and code)
We couple a field experiment with behavioral measures in Liberia to try to work out whether community driven development interventions affect the ways that communities can work together. We find no evidence for adverse effects and some surprisingly strong evidence that exposure to development aid can strengthen the ability of communities to work together.

Experiments:
2009 "Field Experiments and the Political Economy of Development"  (with J Weinstein) Annual Review of Political Science
There is a lot of potential for researchers and development organizations to work together to use experimental approaches in order to learn about basic development processes. We describe the opportunities and limitations of this approach.

Rebel Recruitment:
2008 "Who Fights?" (with J Weinstein). American Journal of Political Science. Data
We use data from our survey of rebels and self defense militia to try to work out why some people take part in violent movements. We find that poverty is a strong driver, but inconsistent with the classic grievance hypothesis, we find that poverty is associated with people joining both sides of the war.

Decision-making between fragmented groups:
2008 "Existence of a Multicameral Core"   Social Choice and Welfare   | Additional Material
In formal models of majority rule we know that if a single group makes a decision an equilibrium typically exists at the "median" in one dimension but there is no clear prediction in more than one dimension. Here I show that if n groups jointly make a decision in m dimensions, outcomes lie on a "median hyperplane" if m &le n but difficulties reemerge in higher dimensions.

Game theoretic analysis of coalitions:
2008 "Coalitions." Annual Review of Political Science
I review the formal literature on coalitions and coalition formation. In recent years there has been excellent work linking cooperative to noncooperative approaches. The next frontier in this work is examining how variation in the rules governing how and which contracts are signed affects what sorts of coalitions are likely to form.

Ethnic Diversity and Collective Action:
2007 "Why Does Ethnic Diversity Undermine Public Goods Provision?" (with J Habyarimana, D Posner and J Weinstein) American Political Science Review
This is the article length version of our Coethnicity book.

Post Conflict Demobilization:
2007 "Demobilization and Reintegration"  (with J Weinstein) Journal of Conflict Resolution Data
Lots of resources are put into assisting excombatants return to civilian life. But we don't understand the reintegration process well and whether interventions to support it are effective. We find that a history of abuse is a good predictor of reintegration difficulties but we find no evidence of the effectiveness of UN programs (although we emphasize that no evidence of an effect is not the same as evidence of no effect!).

Deliberative Democracy:
2007 "The Role of Leadership in Democratic Deliberations: Results from a Field Experiment in São Tomé and Príncipe"  (with M E Sandbu and W A Masters) World Politics
We use a field experiment to work out how participatory processes really are. We examine an ambitious exercise in deliberative democracy in Sao Tome e Principe and find that outcomes of group deliberations are strongly determined by who happens to be facilitating the discussions. Participatory processes may be much more open to manipulation than we tend to think.

Bargaining:
2007 "Strategic Ratification"   Public Choice
I examine the conjecture that bargainers are much more effective when their deals are subject to ratification by third parties with different preferences to their own. By examining a general setting in which ratifiers are fully strategic I find conditions under which this conjecture holds.

Managing Natural Resources:
2007. Escaping the Resource Curse (Co-edited with J D Sachs, and J E Stiglitz) | "What Is the Problem with Natural Resource Wealth?" | "Future Directions for the Management of Natural Resources"
We gathered a group of leading scholars and practitioners to think through what strategies can be used to make sure that natural resource endowments do a country more good than harm (perversely having lots of natural resources often leads to lots of problems). The recommendations range from technical advice on contract negotiations and auction design to proposals for international institutions and norms that will support rather than exploit producing countries.
2007 "The Political Economy of Natural Resource Funds," (with M Sandbu) in Humphreys, Sachs, and Stiglitz (eds.) Escaping the Resource Curse | Formal Model | Data
In this chapter we propose a political economy model to help understand the incentives to consume natural resource wealth too quickly. A core problem we identify is that political instability reduce the incentives for politicians to spend optimally. We describe a set of design elements that could help address the credibility issues that underlie this problem.

The Treatment of Civilians in Civil War:
2006 "Handling and Manhandling Civilians in Civil War" (with J Weinstein) American Political Science Review | Formal Model
We seek to understand why some fighting factions are so much more abusive to civilian populations than others. There are many possible reasons for this; in the Sierra Leone case variation in the discipline of subfactional units appears best able to account for behavior with civilians. Within both the rebel and the militia groups abuses were significantly more limited in the more disciplined units.

Conflict Onset and Duration:
2005 "Natural Resources, Conflict, and Conflict Resolution"   Journal of Conflict Resolution | ( JCR link ) | Data
I examine what mechanisms might underpin the relationship between natural resource endowments and conflict. There are many possible culprits but overall explanations that focus on the adverse effects of resources on state structures seem more accurate than explanations that focus on rebel greed.
2005 "Senegal and Mali: A Comparative Study of Rebellions in West Africa" (with H Ag Mohamed) in Collier and Sambanis Understanding Civil War Africa: Africa Evidence And Analysis
We examine the origin and duration of two secessionist wars in West Africa. Resource endowments do not help account for the origins of the wars although they may help explain the duration of the Senegal conflict. More important factors appear to be patterns of within country inequality as well as regional neighborhood effects.

Democracy and Growth:
2005 " Political Institutions and Economic Policies: Lessons from Africa" (with Robert Bates.) British Journal of Political Science (2005) 35:403-428 | Data We examine the effects of democratic institutions on policy choices; more competitive systems we find are associated with less corruption but not with a greater propensity to adopt "Washington Consensus" policies.

Other Writing on Natural Resources
2005. "Natural Resources and Armed Conflicts: Issues and Options" in Ballentine and Nitzschke Profiting from Peace: Managing the Resource Dimensions of Civil War Boulder: Lynne Reinner
2004 Model Oil Law " | "Explanatory Notes" Developed for Sao Tome e Principe, with J Bell, T Faria, P Rosenblum, M E Sandbu.

Published Reviews, Policy Papers, and Other Working Papers
2011 "Ethnicity and the Politics of AIDS - A Discussion of Boundaries of Contagion: How Ethnic Politics Have Shaped Government Responses to AIDS" in Perspective on Politics
2011 "Ethical Challenges of Embedded Experimentation"   Some reflections of when and how it is ethical to engage in embedded field experimentation. (Comparative Democratization Article)
2009 "Community based Reintegration in Aceh" in Indonesian Social Development Papers 12 (with P Barron, L Paler, and J Weinstein)
2009 "Development Assistance, Institution Building, and Social Cohesion after Civil War: Evidence from a Field Experiment in Liberia" CGD Working Paper 194 (with J Fearon and J Weinstein)
2009 "Evaluating Community-Driven Reconstruction: Lessons from post-conflict Liberia" Development Outreach World Bank Institute (with J Fearon and J Weinstein)
2005 "Prospects and Opportunities for Achieving the MDGs in Post-conflict Countries: A Case Study of Sierra Leone and Liberia" CGSD Working Paper No. 27 (with P Richards)
2004 "Violent Conflict and the Millennium Development Goals: Diagnosis and Recommendations." CGSD Working Paper No. 19 (with A Varshney)
2004 "What the Fighters Say: A Survey of Ex-Combatants in Sierra Leone."   CGSD Working Paper No. 20, (with J Weinstein and PRIDE-Salone) | Survey
2004 Review of States and Markets: A Primer in Political Economy by Adam Przeworski.   Political Science Quarterly
2003 "Aspects économiques des guerres civiles" Revue Tiers Monde 174 (April - June 2003)
2000 African Entrepreneurship: Muslim Fula Merchants in Sierra Leone by Alusine Jalloh. H-AfrPol.

Other
2007 "Placing and Passing: Evidence from Uganda on Ethnic Identification and Ethnic Deception" (with J Habyarimana, D Posner and J Weinstein)
2006 "Social Focal Points" (with J Habyarimana, D Posner and J Weinstein)
2003 "Economics and Violent Conflict."
2001 "To Bargain or to Brawl? Political Decision-making in Institutionally Weak Environments."
2000 "Salience" (with J Garry)
2000 "Trade and Poverty: A CGE Model for South Africa"

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