The Effect of High School Matriculation Awards: Evidence from Randomized Trials

In Israel, as in many other countries, a high school matriculation certificate is required by universities and some jobs. In spite of the certificate's value, Israeli society is marked by vast differences in matriculation rates by region and socioeconomic status. We attempted to increase the likelihood of matriculation among low-achieving students by offering substantial cash incentives in two demonstration programs. As a theoretical matter, cash incentives may be helpful if low-achieving students reduce investment in schooling because of high discount rates, part-time work, or face peer pressure not to study. A small pilot program selected individual students within schools for treatment, with treatment status determined by previous test scores and a partially randomized cutoff for low socioeconomic status. In a larger follow-up program, entire schools were randomly selected for treatment and the program operated with the cooperation of principals and teachers. The results suggest the Achievement Awards program that randomized treatment at the school level raised matriculation rates, while the student-based program did not.

Determining Pesticide and Nitrate Levels in Spring Water in Northwest Arkansas

Occurrences of pesticides in our nations ground water are on the rise. As states become aware of this problem and begin monitoring programs, incidence of contamination will probably increase. Since the problem of pesticides in groundwater is relatively new, little research has centered on the fate of pesticides after they reach the groundwater environment. In Northwest Arkansas efforts to monitor groundwater for pesticides have been small. Twenty-five springs in Northwest Arkansas were sampled in the fall of 1988, and spring of 1989. Analysis for atrazine, alachlor, metolachlor, diuron, and simazine in spring water was preformed using gas liquid chromatography and high performance liquid chromatography. No detectable residues of any of the selected pesticides were found. Northwest Arkansas is a leader in poultry production. Much of the manure from poultry houses is spread on the sourounding pastures. As this litter decomposes nitrates and phosphates are released. Nitrate and phosphate concentrations were also determined on water from the spring samples. No spring exceeded the EPA\u27s limit of 45 mg/L for nitrate in drinking water. The highest concentration for phosphate in any spring was 1.05 mg/L

Minimizing the Potential for Groundwater Contamination from Agricultural Point Sources

An activated charcoal filtration unit was designed to remove pesticides from leftover pesticide solutions and rinsates generated under farm-like conditions. The system, fabricated for less than $1400 using readily available components, effectively removed the pesticides atrazine, benomyl, carbaryl, fluometuron, metolachlor, and trifluralin from wastewater generated on the University of Arkansas Agronomy Farm located in Fayetteville, AR. A total of 2253 L of wastewater were treated using the system. Of these 1768 L were generated from washing out the spray tank (rinsates) while 485 L stemmed from leftover pesticide solutions that were mixed, but not applied. Typical initial pesticide concentrations in the wastewater were on the order of 500 to 1000 parts per million (ppm). The final pesticide concentrations remaining after charcoal filtration were generally less than 10 ppm. Approximately 1514 L of wastewater was treated with 23 kg of charcoal before the charcoal was replaced. This resulted in an estimated pesticide loading rate on the charcoal of 0.05 to 0.10 kg pesticide active ingredient per kg activated charcoal. Incubation of alachlor-treated charcoal with a mixed culture of microorganisms resulted in approximately a 30% loss of alachlor after 21 d. These results suggest that on-site degradation of spent charcoal may be a feasible alternative to incineration, however more research is needed to fully determine its potential. A reduced adsorption of methylene blue dye with increasing amounts of trifluralin sorbed to charcoal occurred. Activated charcoal treated with 222 mg/g trifluralin sorbed only 19% of the amount sorbed by the control with no trifluralin present. These results suggest that methylene blue or other dyes might be used to indicate the remaining adsorptive capacity of a charcoal used for removing pesticides from wastewater

Does Immigration Affect the Long-Term Educational Outcomes of Natives? Quasi-Experimental Evidence

This paper uses the mass migration wave to Israel in the 1990s to examine the impact of immigrant concentration in elementary school on the long-term academic outcomes of native students in high school. To identify the causal effect of immigrant children on their peers, we exploit random variation in the number of immigrants across grades within the same school. The results suggest that the overall presence of immigrants had essentially no effect on the quality of the high school attended by native Israelis and on dropout rates, and at most a mild negative effect on high school matriculation rates. However, when we break up the sample by parents' education and by ethnic origin, we find that disadvantaged children were more likely to have been adversely affected by a higher immigrant concentration in elementary school. Focusing on the impact of Ethiopian immigrants who are from a much lower socio-economic background, we find stronger evidence of adverse effects, especially for disadvantaged students and in classes where immigrant concentration was particularly high.

The Effect of High Stakes High School Achievement Awards : Evidence from a School-Centered Randomized Trial

In many countries, college-bound high school seniors must pass a test or series of tests. In Israel, this requirement is known as the ?Bagrut?, or matriculation certificate, obtained by passing a series of subject tests. In spite of the Bagrut?s value, Israeli society is marked by vast differences in Bagrut rates by region and socioeconomic status. We attempted to increase the likelihood of Bagrut certification among low-achieving students by offering substantial cash incentives to high school seniors in an experimental demonstration program. As a theoretical matter, such incentives may be helpful if low-achieving students reduce investment in schooling because of high discount rates, part-time work, or face peer pressure not to study. The experiment studied here used a school-based randomization design offering awards to all students in treated schools who passed their exams. Randomization was imperfect because of the clustered design. We discuss alternative strategies for dealing with clustering in research of this type. On balance, the estimates point to a substantial and statistically significant treatment effect for students close to the margin for certification. We also look at a number of mediating outcomes in an effort to determine how students responded to incentives. These results show students took more tests and were more likely to accumulate the number of credit units required for Bagrut success

New evidence on the causal link between the quantity and quality of children

A longstanding question in the economics of the family is the relationship between sibship size and subsequent human capital formation and economic welfare. If there is a causal quantity-quality tradeoff, then policies that discourage large families should lead to increased human capital, higher earnings, and, at the macro level, promote economic development. Ordinary least squares regression estimates and a large theoretical literature suggest that this is indeed the case. This paper presents new evidence on the child-quantity/child-quality trade-off. Our empirical strategy exploits exogenous variation in family size due to twin births and preferences for a mixed sibling-sex composition, as well as ethnic differences in the effects of these variables and preferences for male births in some ethnic groups. We use these sources of variation to look at the causal effect of family size on completed educational attainment, fertility, and earnings. For the purposes of this analysis, we constructed a unique matched data set linking Israeli Census data with information on the demographic structure of families drawn from a population registry. Our results show no evidence of a quantity-quality trade-off, though some estimates from one subsample suggest that first-born girls from large families marry sooner

Maimonides rule redux

We use Maimonides' rule as an instrument for class size in large Israeli samples from 2002–2011. In contrast with Angrist and Lavy (1999), newer estimates show no evidence of class size effects. The new data also reveal enrollment manipulation near Maimonides cutoffs. A modified rule that uses birthdays to impute enrollment circumvents manipulation while still generating precisely estimated zeros. In both old and new data, Maimonides' rule is unrelated to socioeconomic characteristics conditional on a few controls. Enrollment manipulation therefore appears to be innocuous. We briefly discuss possible explanations for the disappearance of Israeli class size effects since the early 1990s

Does immigration affect the long-term educational outcomes of natives? Quasi-experimental evidence

This paper uses the mass migration wave to Israel in the 1990s to examine the impact of immigrant concentration during elementary school on the long-term academic outcomes of native students in high school. To identify the causal effect of immigrant children on their native peers, the empirical strategy must address two sources of bias: the endogenous sorting of immigrants across schools, and the endogenous grade placement of immigrants within schools. We control for the endogeneity of immigrant placement across schools by conditioning on the total number of immigrants in a school and exploit random variation in the number of immigrants across grades within the same school. To address the endogenous grade placement of immigrants within schools, we use the immigrants' dates of birth as an instrument for their actual grade placement. The results suggest that the overall presence of immigrants in a grade had a significant and large adverse effect on two important outcomes for Israeli natives: the dropout rate and the chances of passing the high school matriculation exam which is necessary to attend college

A simple method to assess the oxidative susceptibility of low density lipoproteins

BACKGROUND: Oxidative modification of low density lipoproteins (LDL) is recognized as one of the major processes involved in atherogenesis. The in vitro standardized measurement of LDL oxidative susceptibility could thus be of clinical significance. The aim of the present study was to establish a method which would allow the evaluation of oxidative susceptibility of LDL in the general clinical laboratory. RESULTS: LDL was isolated from human plasma by selective precipitation with amphipathic polymers. The ability of LDL to form peroxides was assessed by measuring thiobarbituric acid reactive substances (TBARS) after incubation with Cu(2+) and H(2)O(2). Reaction kinetics showed a three-phase pattern (latency, propagation and decomposition phases) which allowed us to select 150 min as the time point to stop the incubation by cooling and EDTA addition. The mixture Cu(2+)/H(2)O(2) yielded more lipoperoxides than each one on its own at the same time end-point. Induced peroxidation was measured in normal subjects and in type 2 diabetic patients. In the control group, results were 21.7 ± 1.5 nmol MDA/mg LDL protein, while in the diabetic group results were significantly increased (39.0 ± 3.0 nmol MDA/mg LDL protein; p < 0.001). CONCLUSION: a simple and useful method is presented for the routine determination of LDL susceptibility to peroxidation in a clinical laboratory

Paradoxical effects of Worrisome Thoughts Suppression: the influence of depressive mood

Thought suppression increases the persistence of unwanted idiosyncratic worries thoughts when individuals try to suppress them. The failure of suppression may contribute to the development and maintenance of emotional disorders. Depressive people seem particulary prone to engage in unsuccessful mental control strategies such as thought suppression. Worry has been reported to be elevated in depressed individuals and a dysphoric mood may also contribute for the failure of suppression. No studies examine, however, the suppression of worisome thoughts in individuals with depressive symptoms. To investigate the suppression effects of worrisome thoughts, 46 participants were selected according to the cut-off score of a depressive symptomatology scale and they were divided in two groups (subclinical and nonclinical group). All the individuals took part in an experimental paradigm of thought suppression. The results of the mixed factorial analysis of variance revealed an increased frequency of worrisome thoughts during the suppression phase on depending of the depressive symptoms. These findings confirm that depressive mood can reduce the success of suppression.info:eu-repo/semantics/publishedVersio