Alleviating transitory food crisis in Africa : international altruism and trade

This paper focuses on criticism about the use of emergency food aid in sub-Saharan Africa. More specifically, it examines the response of the donor community to unexpected or transitory drops in domestic food production in 26 countries. The study compares the role of food aid and commercial food imports in offsetting these shocks and covering the shortfall in food consumption. Several hypotheses that determine the tendency of donors to respond to the needs of different countries are tested. The results suggest that food aid and commercial food imports stabilize food consumption and neutralize the effects of random shocks to domestic production. Food aid compensates for up to 50 percent of the drop in food production; imports make up an additional 30 percent. This paper documents the stylized facts of food insecurity in Africa and shows the relative importance of emergency and total food aid to food production and food shortages. The paper includes an empirical framework for the estimation and analysis of the correlation between food aid and food production and presents the results. Lastly, the paper elaborates on the economic and political determinants that affect the global response to the emergency needs of countries in Africa.Food&Beverage Industry,Food&Nutrition Policy,Development Economics&Aid Effectiveness,Environmental Economics&Policies,School Health

Do Gender Stereotypes Reduce Girls' Human Capital Outcomes? Evidence from a Natural Experiment

Schools and teachers are often said to be a source of stereotypes that harm girls. This paper tests for the existence of gender stereotyping and discrimination by public high-school teachers in Israel. It uses a natural experiment based on blind and non-blind scores that students receive on matriculation exams in their senior year. Using data on test results in several subjects in the humanities and sciences, I found, contrary to expectations, that male students face discrimination in each subject. These biases widen the female male achievement gap because girls outperform boys in all subjects, except English, and at all levels of the curriculum. The bias is evident in all segments of the ability and performance distribution and is robust to various individual controls. Several explanations based on differential behavior between boys and girls are not supported empirically. However, the size of the bias is very sensitive to teachers' characteristics, suggesting that the bias against male students is the result of teachers', and not students', behavior.

Do Differences in Schools’ Instruction Time Explain International Achievement Gaps? Evidence from Developed and Developing Countries

The time that children spend in school varies across countries. Do these differences explain international gaps in pupils’ academic achievements? In this paper, I estimate the effects of instructional time on students’ achievement using PISA 2006 data, which includes data samples from over 50 countries. I find that instructional time has a positive and significant effect on test scores, and that the effect is much lower in developing countries. Evidence also suggests that the productivity of instructional time is higher in countries which implemented school accountability measures or that gave schools autonomy in budgetary decisions and in hiring/firing teachers.

Does food aid depress food production? The disincentive dilemma in the African context

Food aid averages only ten percent of total financial aid to developing countries, but in certain African countries - Botswana, Cape Verde, Mauritius, and Mauritania - it represents more than half the food available for consumption. The author applies vector auto-regression (VAR) analysis to data for sub-Saharan Africa to test these hypotheses. The issue is not whether food aid is good or bad but how it can be used to promote economic development and improve the nutrition of the food-insecure. The author found that food aid has a significant positive effect on food production. Any disincentive induced by the additional supply of food is offset by the positive effects. Food aid is also more likely to have a positive effect in countries that use fertilizer intensively. One possible explanation for this is that countries that enjoy a relative abundance of regular food aid can use the resources made available through reduced food imports to invest more in the agricultural sector - which is more likely when such an investment is a condition imposed by the aid donors.Food&Beverage Industry,Food&Nutrition Policy,Development Economics&Aid Effectiveness,Environmental Economics&Policies,School Health

How responsive is investment in schooling to changes in redistributive policies and in returns?

This paper uses an unusual pay reform to test the responsiveness of investment in schooling to changes in redistribution schemes that increase the rate of return to education. We exploit an episode where different Israeli kibbutzim shifted from equal sharing to productivity-based wages in different years and find that students in kibbutzim that reformed earlier invested more in high school education. This effect is stronger for males and is largely driven by students whose parents have lower levels of education. We also show that, in the long run, students in kibbutzim that reformed earlier were more likely to complete post-high school academic colleges. Our findings support the prediction that education is highly responsive to changes in the redistribution policy, especially for students from weaker backgrounds

Fixed-point spectrum for group actions by affine isometries on Lp-spaces

The fixed-point spectrum of a locally compact second countable group G on lp is defined to be the set of real numbers p such that every action by affine isometries of G on lp admits a fixed-point. We show that this set is either empty, or is equal to a set of one of the following forms : [1,\pc[, [1,\pc[\{2} for some \pc<\infty or \pc=\infty, or [1,\pc], [1,\pc]\{2} for some pc<infty. This answers a question closely related to a conjecture of C. Drutu which asserts that the fixed-point spectrum is connected for isometric actions on Lp(0,1). We also study the topological properties of the fixed-point spectrum on Lp(X,\mu) for general measure spaces (X,\mu), and show partial results toward the conjecture for actions on Lp(0,1). In particular, we prove that the spectrum F_{L^{\infty}(X,\mu)(G,\pi) of actions with linear part \pi is either empty, or an interval of the form [1,\pc] or [1,\infty[, whenever \pi is an orthogonal representation associated to a measure-preserving ergodic action on a finite measure space (X,\mu).Comment: 25 page

Mechanisms and Impacts of Gender Peer Effects at School

The consequences of gender social and learning interactions in the classroom are of interest to parents, policy makers, and researchers. However, little is known about gender peer effects in schools and their operational channels. In this paper, we estimate the effects of classroom gender composition on scholastic achievements of boys and girls in Israeli primary, middle, and high schools and identify the mechanisms through which these peer effects are enacted. In particular, we examine whether gender peer effects work through changes in classroom learning and social environment, teaching methods and pedagogy, and teacher burnout and work satisfaction. In assessing these mechanisms, we distinguish between the effects generated by changes in the classroom gender composition and those generated by changes in the behavior of students. To control for potentially confounding unobserved characteristics of schools and students that might be correlated with peer gender composition, we rely on idiosyncratic variations in gender composition across adjacent cohorts within the same schools. Our results suggest that an increase in the proportion of girls leads to a significant improvement in students' cognitive outcomes. The estimated effects are of similar magnitude for boys and girls. As important mechanisms, we find that a higher proportion of female peers lowers the level of classroom disruption and violence, improves inter-student and student-teacher relationships as well as students' overall satisfaction in school, and lessens teachers' fatigue. We find, however, no effect on individual behavior of boys or girls, which suggests that the positive peer effects of girls on classroom environment are due mostly to compositional change, namely due to having more girls in the classroom and not due to improved behavior of peers.

Targeted Remedial Education for Under-Performing Teenagers: Costs and Benefits

There is renewed interest in ways to enhance secondary education, especially among disadvantaged students. This study evaluates the short-term effects of a remedial-education program that provided additional instruction to under-performing high-school students in Israel. The program targeted 10th twelfth graders who needed additional help to pass the matriculation exams. Using a comparison group of schools that enrolled in the program later and implementing a differences-in-differences estimation strategy, we found that the program raised the school mean matriculation rate by 3.3 percentage points. This gain reflects mainly an effect on targeted participants and the absence of externalities on their untreated peers. The program was found to be less cost-effective than two alternative interventions based on incentives for teachers and students.

Influence of Rice Production on the Quality of Water in Tailwater Collection Reservoirs

Since maintaining high water quality standards in the state remains a high priority, monitoring for pesticides in water sources must continue. Determining the type, concentration, and characteristics of any pesticides present in water supplies are essential to the overall assessment of water quality. Five independent locations, implementing contained water management systems and recyclable water, were monitored in 1995 and 1996. Irrigation, runoff, and pond water samples were collected every 10 to 14 days between permanent flood establishment and draining. Water samples were transported to the laboratory and extracted for 16 pesticides using solid phase extraction (SPE) techniques. Quantification and confirmation of pesticide residues were obta1ned by HPLC and GC/MS analysis. The lower limit of quantitation for all pesticides was between 1.0 -1.3 pg L-1 in water. Pesticides selected for monitoring were determined after assessing state recommendations and our analytical capabilities. Pesticides included: benomyl, bensulfuron methyl, carbaryl, carbofuran, 2,4-D, fenoxaprop ethyl, propiconazole, malathion, MCPA, methyl parathion, molinate, pendimethalin, propanil, iprodione, quinclorac, triclopyr, and thiobencarb. Since each field location was independently managed, individual results are site specific. 2,4-D, benomyl, molinate, propanil, quinclorac, thiobencarb, and pendimethalin were the pesticides actually applied during the seasons. These pesticides were detected, usually at trace levels, in tailwaters shortly after application but did not appear to buildup in the reservoirs. Quinclorac residues in the tailwaters were more persistent (up to 8 weeks) than the other detected compounds (less than 2 weeks)