Inequality and a Repeated Joint Project

Agents voluntarily contribute to an infinitely repeated joint project. We investigate the conditions for cooperation to be a renegotiation-proof and coalition-proof equilibrium before examining the influence of output share inequality on the sustainability of cooperation. When shares are not equally distributed, cooperation requires agents to be more patient than under perfect equality. Beyond a certain degree of share inequality, full efficiency cannot be reached without redistribution. This model also explains the coexistence of one cooperating and one free-riding coalition. In this case, increasing inequality can have a positive or negative impact on the aggregate level of effort.

Life and Death of Roscas : If Power Corrupts, Does Powerlessness Make One Blameless ?

We have very few ideas as to what factors can influence the duration of roscas and reduce their failure risk. In this research, we bring new light on these empirical questions using an original data set containing information on living and dead roscas from Cotonou, Benin. We notice that the groups run by a president alone are more likely to fall apart. We also present evidence that individuals attracted to this type of groups have a lower social capital and therefore might be more likely to default.ROSCA ; Survival Analysis ; Governance structure ; Benin

Rosca Participation in Benin : a Commitment Issue

In the light of first-hand data from a Beninese urban household survey in Cotonou, we investigate several motives aiming to explain participation in Rotating Savings and Credit ASsociations. We provide empirical findings which indicate that individuals use their participation in a rosca as a device to discipline themselves to save money and commit against problems of self-control.ROSCA, self-control, Benin, Intra-Household Allocation, Saving, Household Survey, Development Finance

Rosca Participation in Benin: a Commitment Issue

In the light of first-hand data from a Beninese urban household survey in Cotonou, we investigate several motives aiming to explain participation in Rotating Savings and Credit ASsociations. We provide anecdotal pieces of evidence, descriptive statistics, FIML regressions and matching estimates which tend to indicate that most individuals use their participation in a rosca as a device to commit themselves to save money and to deal with self-control problems.ROSCA, self-control, commitment device, Benin

Inequality and Inefficiency in Joint Projects

A group of agents voluntarily participates in a joint project, in which efforts are not perfectly substitutable. The output is divided according to some given vector of shares. A share vector is unimprovable if no other share vector yields a higher sum of payoffs. When the elasticity of substitution across efforts is two or lower, only the perfectly equal share vector is unimprovable, and all other vectors can be improved via Lorenz domination. For higher elasticities of substitution, perfect equality is no longer unimprovable. Our results throw light on the connections between inequality and collective action.Inequality, Collective Action, Substitutability

Is it all about Money? A Randomized Evaluations of the Impact of Insurance Literacy and Marketing Treatments on the Demand for Health Microinsurance in Senegal

In Senegal mutual health organizations (MHOs) have been present in the greater region of Thiès for years. Despite their benefits, in some areas there remain low take-up rates. We offer an insurance literacy module, communicating the benefits from health microinsurance and the functioning of MHOs, to a randomly selected sample of households in the city of Thiès. The effects of this training, and three cross-cutting marketing treatments, are evaluated using a randomized control trial. We find that the insurance literacy module has no impact, but that our marketing treatment has a significant effect on the take up decisions of households.community based health insurance scheme; Randomized control trials; Africa; Senegal

Is it all about Money? A Randomized Evaluation of the Impact of Insurance Literacy and Marketing Treatments on the Demand for Health Microinsurance in Senegal

In Senegal mutual health organizations (MHOs) have been present in the greater region of Thiès for years. Despite their benefits, in some areas there remain low take-up rates. We offer an insurance literacy module, communicating the benefits from health microinsurance and the functioning of MHOs, to a randomly selected sample of households in the city of Thiès. The effects of this training, and three cross-cutting marketing treatments, are evaluated using a randomized control trial. We find that the insurance literacy module has no impact, but that our marketing treatment has a significant effect on the take up decisions of households.Community based health insurance scheme, Randomized control trials, Africa, Senegal

Long-term strict raw food diet is associated with favourable plasma b-carotene and low plasma lycopene concentrations in Germans

Dietary carotenoids are associated with a reduced risk of chronic diseases. Raw food diets are predominantly plant-based diets that are practised with the intention of preventing chronic diseases by virtue of their high content of beneficial nutritive substances such as carotenoids. However, the benefit of a long-term adherence to these diets is controversial since little is known about their adequacy. Therefore, we investigated vitamin A and carotenoid status and related food sources in raw food diet adherents in Germany. Dietary vitamin A, carotenoid intake, plasma retinol and plasma carotenoids were determined in 198 (ninety-two male and 106 female) strict raw food diet adherents in a cross-sectional study. Raw food diet adherents consumed on average 95 weight% of their total food intake as raw food (approximately 1800 g/d), mainly fruits. Raw food diet adherents had an intake of 1301 retinol activity equivalents/d and 16·7 mg/d carotenoids. Plasma vitamin A status was normal in 82% of the subjects ($1·05mmol/l) and 63$0·88 mmol/l). In 77% of subjects the lycopene status was below the reference values for average healthy populations (,0·45mmol/l). Fat contained in fruits, vegetables and nuts and oil consumption was a significant dietary determinant of plasma carotenoid concentrations (b-carotene r 0·284; P,0·05; lycopene r 0·168; P¼0·024). Long-term raw food diet adherents showed normal vitamin A status and achieve favourable plasma b-carotene concentrations as recommended for chronic disease prevention, but showed low plasma lycopene levels. Plasma carotenoids in raw food adherents are predicted mainly by fat intake

Selecting informative food items for compiling food-frequency questionnaires: comparison of procedures

The authors automated the selection of foods in a computer system that compiles and processes tailored FFQ. For the selection of food items, several methods are available. The aim of the present study was to compare food lists made by MOM2, which identifies food items with highest between-person variance in intake of the nutrients of interest without taking other items into account, with food lists made by forward regression. The name MOM2 refers to the variance, which is the second moment of the nutrient intake distribution. Food items were selected for the nutrients of interest from 2 d of recorded intake in 3524 adults aged 25–65 years. Food lists by 80 % MOM2 were compared to those by 80 % explained variance for regression on differences between the number and type of food items, and were evaluated on (1) the percentage of explained variance and (2) percentage contribution to population intake computed for the selected items on the food list. MOM2 selected the same food items for Ca, a few more for fat and vitamin C, and a few less for carbohydrates and dietary fibre than forward regression. Food lists by MOM2 based on 80 % of variance in intake covered 75–87 % of explained variance for different nutrients by regression and contributed 53–75 % to total population intake. Concluding, for developing food lists of FFQ, it appears sufficient to select food items based on the contribution to variance in nutrient intake without taking covariance into accoun

Reliability of Semiautomated Kinetic Perimetry (SKP) and Goldmann Kinetic Perimetry in Children and Adults With Retinal Dystrophies.

PurposeTo investigate the precision of visual fields (VFs) from semiautomated kinetic perimetry (SKP) on Octopus 900 perimeters, for children and adults with inherited retinal degenerations (IRDs). Goldmann manual kinetic perimetry has long been used in the diagnosis and follow-up of these patients, but SKP is becoming increasingly common. Octopus VFs (OVFs) and Goldmann VFs (GVFs) were both mapped on two occasions.MethodsNineteen females and 10 males with IRDs were tested on OVFs and GVFs, with two targets per test (V4e and one smaller target). Tests were performed in the same (randomized) order at two visits about 1 week apart. The VFs were digitized to derive isopter solid angles. Comparisons, within and between visits, were performed with paired t-tests and Bland-Altman plots.ResultsMedian age was 20 years (range, 7-70; 10 participants aged ≤17 years old). There were no significant differences in solid angles between OVFs and GVFs (P ≥ 0.06) or between the two visits' solid angles on either perimeter (P ≥ 0.30). Between-visit test-retest variability for GVFs and OVFs was similar (P ≥ 0.73), with median values of approximately 9% to 13%. Overall variability was lower for children than adults (medians of 7.5% and 12.8%, respectively).ConclusionsOctopus SKP and Goldmann perimetry produced VFs of similar size and variability.Translational relevanceOur study indicates that SKP provides a viable alternative to traditional Goldmann perimetry in clinical trials or care involving both children and adults with IRDs