Jordan Loper, Alberto Prati

phd seminar

Jordan Loper, Alberto Prati


IBD Salle 16

Îlot Bernard du Bois - Salle 16

5-9 boulevard Maurice Bourdet
13001 Marseille

Mardi 26 février 2019| 12:30 - 14:00

Océane Piétri : oceane.pietri[at]
Morgan Raux : morgan.raux[at]
Laura Sénécal : laura.senecal[at]


Jordan Loper
Women's position in ancestral societies and female HIV: the long-term effect of matrilineality in Sub-Saharan Africa

While 80 percent of all HIV-positive women in the world live in sub-Saharan Africa, there is substantial variation in infection rates across the continent. This paper traces current variation in female HIV rates within Sub-Saharan Africa to women's position in pre-colonial ethnic group's kinship organizations. In matrilineal kinship systems, lineage and inheritance are traced through female members. The structure of matrilineal kinship systems implies that, relative to patrilineal kinship systems, women have greater support from their own kin groups, and husbands have less authority over their wives. Using within-country variation across about 280,000 individuals in their ethnic group's ancestral kinship organization, in 18 countries, I show that females originating from ancestrally matrilineal ethnic groups are today more likely to be infected by HIV. I show that this result is robust to the inclusion of subnational fixed effects, as well as a large set of cultural, historical, geographical, and environmental factors that could be confounding the estimates. Further, I underline that my result is not driven by differential selection into HIV testing, nor by differences in general health status, but is specific to sexually transmitted diseases. I provide several mechanisms to this result: first, benefiting from more sexual autonomy, matrilineal women adopt riskier sexual practices which are more conducive to HIV. Second, despite a better ability to impose safe sexual practices to their husbands, matrilineal women are less likely to use protective contraception methods such as male condom. I provide evidences that behavioural mechanisms are driving this counterintuitive result: I find that, relative to their patrilineal counterparts, matrilineal women are more likely to (1) perceive condom as an ex-post protective method against HIV transmission rather than an ex-ante preventive method against HIV infection; (2) underestimate their husband's propensity to be unfaithful. I conjecture that this latter result is an adverse effect of matrilineal women's overestimation of the efficiency of their intrahousehold threatening strategy against male infidelity.

Alberto Prati
Asymmetric feedback recall: the role of affect, co-écrit avec Charlotte Saucet

Self-relevant feedback is one of the main sources of information about oneself: it may help individuals filling an informational gap, updating beliefs, making better subsequent choices and thus leading to superior outcomes. However, feedback retrieval is known to depend on the valence of the feedback, positive feedback being more likely to be recalled than negative one. The reason for this asymmetry is still unclear: do people prioritize positive information to enhance their self-image (self-enhancement effect), or is positive information easier to recall for subjects in non-negative mood (mood-congruent effect)? In a laboratory experiment, we investigate whether mood induction before retrieval can turn off this asymmetry in feedback recall. We manipulate participant's mood (positive, negative and neutral) before asking them to recall past feedback on their relative performance in an intelligence task.