Migration and Remittances in South Africa : the role of political factors.

This paper looks at the determinants of international remittances in the case of South-South migrations. Using micro-economic data from a survey conducted in 2006, analysis was carried out on 639 African migrants residing in Johannesburg. Besides the traditional variables (income, household’s size in the host country, age, sex, education…), political variables (regime change in the host country and conditions in the country of origin before the migration including war, and conflict) are used in the analysis. The results highlight the importance of these political variables as determinants of migrants’ probability to remit. The end of the apartheid regime in South Africa impacts positively and significantly the probability of remitting money to the home country while the fact of having fled one’s country of origin because of violence or conflict has the opposite effect. However, the political change in the host country has no influence on the amounts transferred. Once the decision to remit is taken, traditional variables have more of an explanatory power in predicting amounts transferred than political variables.International migration; political environment; South Africa; forced migration; remittance;

Time and Space Optimal Massively Parallel Algorithm for the 2-Ruling Set Problem

In this work, we present a constant-round algorithm for the $2$-ruling set problem in the Congested Clique model. As a direct consequence, we obtain a constant round algorithm in the MPC model with linear space-per-machine and optimal total space. Our results improve on the $O(\log \log \log n)$-round algorithm by [HPS, DISC'14] and the $O(\log \log \Delta)$-round algorithm by [GGKMR, PODC'18]. Our techniques can also be applied to the semi-streaming model to obtain an $O(1)$-pass algorithm. Our main technical contribution is a novel sampling procedure that returns a small subgraph such that almost all nodes in the input graph are adjacent to the sampled subgraph. An MIS on the sampled subgraph provides a $2$-ruling set for a large fraction of the input graph. As a technical challenge, we must handle the remaining part of the graph, which might still be relatively large. We overcome this challenge by showing useful structural properties of the remaining graph and show that running our process twice yields a $2$-ruling set of the original input graph with high probability

Analysis of Blood Stem Cell Activity and Cystatin Gene Expression in a Mouse Model Presenting a Chromosomal Deletion Encompassing Csta and Stfa2l1

The cystatin protein superfamily is characterized by the presence of conserved sequences that display cysteine protease inhibitory activity (e.g., towards cathepsins). Type 1 and 2 cystatins are encoded by 25 genes of which 23 are grouped in 2 clusters localized on mouse chromosomes 16 and 2. The expression and essential roles of most of these genes in mouse development and hematopoiesis remain poorly characterized. In this study, we describe a set of quantitative real-time PCR assays and a global expression profile of cystatin genes in normal mouse tissues. Benefiting from our collection of DelES embryonic stem cell clones harboring large chromosomal deletions (to be reported elsewhere), we selected a clone in which a 95-kb region of chromosome 16 is missing (Del16qB3Δ/+). In this particular clone, 2 cystatin genes, namely Csta and Stfa2l1 are absent along with 2 other genes (Fam162a, Ccdc58) and associated intergenic regions. From this line, we established a new homozygous mutant mouse model (Del16qB3Δ/16qB3Δ) to assess the in vivo biological functions of the 2 deleted cystatins. Stfa2l1 gene expression is high in wild-type fetal liver, bone marrow, and spleen, while Csta is ubiquitously expressed. Homozygous Del16qB3Δ/16qB3Δ animals are phenotypically normal, fertile, and not overtly susceptible to spontaneous or irradiation-induced tumor formation. The hematopoietic stem and progenitor cell activity in these mutant mice are also normal. Interestingly, quantitative real-time PCR expression profiling reveals a marked increase in the expression levels of Stfa2l1/Csta phylogenetically-related genes (Stfa1, Stfa2, and Stfa3) in Del16qB3Δ/16qB3Δ hematopoietic tissues, suggesting that these candidate genes might be contributing to compensatory mechanisms. Overall, this study presents an optimized approach to globally monitor cystatin gene expression as well as a new mouse model deficient in Stfa2l1/Csta genes, expanding the available tools to dissect cystatin roles under normal and pathological conditions

Determinants and uses of remittances : the case of South-South migration

Cette recherche étudie les transferts de fonds réalisés par les migrants dans le cas des migrations entre pays en développement. À l’aide de données récentes et originales portant sur divers pays d’Afrique, il cherche à i) dresser un panorama général des migrations et des transferts de fonds africains, ii) analyser l’impact des conditions de départ sur le comportement de transfert des migrants, iii) étudier les usages des transferts réalisés dans le cas de migrations forcées, et plus généralement Sud-Sud et iv) établir s’il existe des différences de comportement selon les pays de destination des migrants (pays développés ou en développement). Les résultats montrent que les conditions de départ jouent un rôle déterminant dans la décision de transférer des migrants et que les transferts de fonds Sud-Sud sont en grande partie utilisés pour financer des dépenses courantes. Ils révèlent également que les comportements de transfert des migrants Sud-Sud et Sud-Nord diffèrent légèrement.The objective of this research is to analyze South-South remittances, i.e. remittances made between developing countries. With recent and original survey data on African countries, its purpose is to i) establish an overview of African migration and remittances, ii) analyze the impact of departure conditions on the migrants’ remittance behavior, iii) study remittance used in the case of forced migration, and more generally in the case of South-South migration and iv) analyze if remittance behavior of South-South migrants differs from those of South-North migrants. Results show that departure conditions play an important role in the migrant’s decision to remit. They also highlight that South-South remittances are largely used to finance consumption expenditures. Finally, results reveal that South-South and South-North migrants behave slightly differently in terms of remittances

Migration and Remittances in South Africa: the role of political factors

This paper looks at the determinants of international remittances in the case of South-South migrations. Using micro-economic data from a survey conducted in 2006, analysis was carried out on 639 African migrants residing in Johannesburg. Because of the diversity of the reasons of migration to South Africa and the regime change in this country, the paper focuses on the impact of the conditions of departure (forced/non forced) and of the political environment in the host country on remittances. So, besides the traditional variables (income, household’s size in the host country, age, sex, education…), the conditions of departure from the country of origin (war, conflict, persecutions), the regime change in the host country and subjective variables (perception of relative wealth, attachment to the country of origin) are used in the analysis. The potential endogeneity bias of the attachment variable is corrected to obtain non biased estimations of the model. The results highlight the importance of the political factors as determinants of remittances. Both the conditions of departure and the political environment in the host country (access to democracy) influence the propensity to remit. The fact of having fled one’s country of origin because of violence or conflict has a negative effect on the propensity to remit, whereas the access to the democracy impacts positively remittances. Subjective variables also impact significantly and positively the transfers. The migrants who follow the political affairs of their country of origin or who think that they were worse off economically before coming in South Africa have a higher propensity to remit

Transferts de fonds des migrants en Afrique du Sud : les conditions de départ du pays d’origine sont-elles déterminantes?

National audienceThis paper looks at the determinants of international remittances in the context of South-South migration. We use a 2006 survey on 639 African migrants living in Johannesburg. In addition to the traditional variables (income, age and education of the migrant, etc.) we consider the impact of departure conditions from the country of origin and subjective variables (perception of relative wealth, attachment to the country of origin) on remittances. The results show that having left the country of origin due to violence has a negative effect on the propensity to remit, whereas the attachment to the country of origin and the perception of a better economic situation in the host country positively influence remittances.A l’aide d’une enquête menée en 2006 auprès de 639 migrants africains présents à Johannesburg (Afrique du Sud), cet article analyse les déterminants des transferts de fonds dans le cas des migrations Sud-Sud. En plus des variables traditionnelles (revenu, âge, éducation du migrant, etc.), l’impact des conditions de départ du pays d’origine sur les transferts est analysé, ainsi que celui de variables subjectives (perception de richesse et attachement du migrant à son pays d’origine). Les résultats montrent qu’avoir fui son pays pour des raisons de violence réduit significativement la propension à transférer tandis que l’attachement et la perception d’une situation économique meilleure dans le pays d’accueil favorisent les transferts

Transferts de fonds des migrants en Afrique du Sud : les conditions de départ du pays d’origine sont-elles déterminantes?

A l’aide d’une enquête menée en 2006 auprès de 639 migrants africains présents à Johannesburg (Afrique du Sud), cet article analyse les déterminants des transferts de fonds dans le cas des migrations Sud-Sud. En plus des variables traditionnelles (revenu, âge, éducation du migrant, etc.), l’impact des conditions de départ du pays d’origine sur les transferts est analysé, ainsi que celui de variables subjectives (perception de richesse et attachement du migrant à son pays d’origine). Les résultats montrent qu’avoir fui son pays pour des raisons de violence réduit significativement la propension à transférer tandis que l’attachement et la perception d’une situation économique meilleure dans le pays d’accueil favorisent les transferts.This paper looks at the determinants of international remittances in the context of South-South migration. We use a 2006 survey on 639 African migrants living in Johannesburg. In addition to the traditional variables (income, age and education of the migrant, etc.) we consider the impact of departure conditions from the country of origin and subjective variables (perception of relative wealth, attachment to the country of origin) on remittances. The results show that having left the country of origin due to violence has a negative effect on the propensity to remit, whereas the attachment to the country of origin and the perception of a better economic situation in the host country positively influence remittances.nonouirechercheNationa

Time and Space Optimal Massively Parallel Algorithm for the 2-Ruling Set Problem

Funding Information: Academy of Finland, Grant 334238. Publisher Copyright: © Mélanie Cambus, Fabian Kuhn, Shreyas Pai, and Jara Uitto; licensed under Creative Commons License CC-BY 4.0.In this work, we present a constant-round algorithm for the 2-ruling set problem in the Congested Clique model. As a direct consequence, we obtain a constant round algorithm in the MPC model with linear space-per-machine and optimal total space. Our results improve on the O(log log log n)-round algorithm by [HPS, DISC'14] and the O(log log ∆)-round algorithm by [GGKMR, PODC'18]. Our techniques can also be applied to the semi-streaming model to obtain an O(1)-pass algorithm. Our main technical contribution is a novel sampling procedure that returns a small subgraph such that almost all nodes in the input graph are adjacent to the sampled subgraph. An MIS on the sampled subgraph provides a 2-ruling set for a large fraction of the input graph. As a technical challenge, we must handle the remaining part of the graph, which might still be relatively large. We overcome this challenge by showing useful structural properties of the remaining graph and show that running our process twice yields a 2-ruling set of the original input graph with high probability.Peer reviewe

Remittance Behaviour of Forced Migrants in Post-Apartheid South Africa

This paper looks at the determinants of South-South remittances. An original dataset of African migrants living in Johannesburg is used. As South Africa attracts both economic and forced migrants, we focus on the impact of the reason of emigration (violence versus economic concerns) on migrants’ remittance behaviour. On the extensive margin, the results show that leaving a home country for reasons of violence decreases the probability of remitting to the home country. On the intensive margin, transferred amounts do not differ according to whether the migrant was forced to migrate or not. When the migrant has decided to remit, it is more his/her current conditions in the host country and traditional factors (income, education, sex, etc.) that determine the amounts transferred. Our results are robust when restricting the definition of forced migration