The formation of community based organizations in sub-Saharan Africa: An analysis of a quasi-experiment.

Previous analyses of the formation and comparison of community based organizations (CBOs) have used cross section data. So, causal inference has been compromised. We obviate this problem by using data from a quai-experiment in which villages were formed by government officials selecting and clustering households. Our findings are as follow: CBO co-memberships are more likely between geographically proximate households and less likely between early and late settlers, members of female headed households are not excluded, in poorer villages CBO co-membership networks are denser and, while wealthier households may have been instrumental in setting up CBOs, poorer households engage shortly afterwards.Community Based Organizations; quasi-experiment; social networks

Who shares risk with whom under different enforcement mechanisms?

We investigate whether available enforcement mechanisms affects who shares risk with whom in sub-Saharan Africa by applying dyadic regression analysis to data from a lab-type experiment, surveys and a genealogical mapping exercise. During the experiment participants were invited to form risk sharing groups under three enforcement mechanisms: external, intrinsic, and extrinsic, i.e., social sanctioning. Dyads similar in age and gender or who belong to the same economic communitybased organizations (CBOs) are more likely to share risk. However, when social sanctioning is possible, co-members in economic CBOs withdraw from group formation and co-religion and marriage ties come to the fore.Barr, A. et al. (2010) Who shares risk with whom under different enforcement mechanisms? ESRC Working Paper, London: ESRC

Who shares risk with whom under different enforcement mechanisms?

We investigate whether available enforcement mechanisms affect who shares risk with whom in sub-Saharan Africa, by applying dyadic regression analysis to data from a lab-type experiment, surveys, and a genealogical-mapping exercise. During the experiment, participants were invited to form risk-sharing groups under three enforcement mechanisms: external, intrinsic, and extrinsic (i.e., social sanctioning). Same-sex dyads and dyads who belong to the same economic community-based organizations (CBOs) are more likely to share risk. However, when social sanctioning is possible, comembers in economic CBOs withdraw from group formation and coreligion, and marriage ties come to the fore

Bridging the gender divide: An experimental analysis of group formation in African villages

Assortative matching occurs in many social contexts. We experimentally investigate gender assorting in sub-Saharan villages. In the experiment, co-villagers could form groups to share winnings in a gamble choice game. The extent to which grouping arrangements were or could be enforced and, hence, the distribution of interaction costs were exogenously varied. Thus, we can distinguish between the effects of homophily and interaction costs on the extent of observed gender assorting. We find that interaction costs matter - there is less gender assorting when grouping depends on trust. In part, this is due to trust based on co-memberships in gender-mixed religions.

Cooperation in polygynous households

Using a carefully designed series of public goods games, we compare, across monogamous and polygynous households, the willingness of husbands and wives to cooperate to maximize household gains. Compared to monogamous husbands and wives, polygynous husbands and wives are less cooperative, one with another, and co-wives are least cooperative, one with another. The husbands’ and wives’ behavior in a corresponding series of inter-household games indicates that these differences cannot be attributed to selection of less cooperative people into polygyny. Finally, behavior in polygynous households is more reciprocal and less apparently altruistic

DELTA-MRI: Direct deformation Estimation from LongiTudinally Acquired k-space data

Longitudinal MRI is an important diagnostic imaging tool for evaluating the effects of treatment and monitoring disease progression. However, MRI, and particularly longitudinal MRI, is known to be time consuming. To accelerate imaging, compressed sensing (CS) theory has been applied to exploit sparsity, both on single image as on image sequence level. State-of-the-art CS methods however, are generally focused on image reconstruction, and consider analysis (e.g., alignment, change detection) as a post-processing step. In this study, we propose DELTA-MRI, a novel framework to estimate longitudinal image changes {\it directly} from a reference image and subsequently acquired, strongly sub-sampled MRI k-space data. In contrast to state-of-the-art longitudinal CS based imaging, our method avoids the conventional multi-step process of image reconstruction of subsequent images, image alignment, and deformation vector field computation. Instead, the set of follow-up images, along with motion and deformation vector fields that describe their relation to the reference image, are estimated in one go. Experiments show that DELTA-MRI performs significantly better than the state-of-the-art in terms of the normalized reconstruction error.Comment: 5 pages, 4 figures, Submitted to ISBI 202

Impact of Ethiopia’s Community Based Health Insurance on household economic welfare

In 2011, the Government of Ethiopia launched a pilot Community-Based Health Insurance (CBHI) scheme. This paper uses three rounds of household survey data, collected before and after the introduction of the CBHI pilot, to assess the impact of the scheme on household consumption, income, indebtedness and livestock holdings. We find that enrolment leads to a 5 percentage point – or 13 percent – decline in the probability of borrowing and is associated with an increase in household income. There is no evidence that enrolling in the scheme affects consumption or livestock holdings. Our results show that the scheme reduces reliance on potentially harmful coping responses such as borrowing. This paper adds to the relatively small body of work which rigorously evaluates the impact of CBHI schemes on economic welfare

Cooperation in polygynous households

Using a carefully designed series of public goods games, we compare, across monogamous and polygynous households, the willingness of husbands and wives to cooperate to maximize household gains. Compared to monogamous husbands and wives, polygynous husbands and wives are less cooperative, one with another, and co-wives are least cooperative, one with another. The husbands’ and wives’ behavior in a corresponding series of inter-household games indicates that these differences cannot be attributed to selection of less cooperative people into polygyny. Finally, behavior in polygynous households is more reciprocal and less apparently altruistic