Judicial Risk and Credit Market Performance: Micro Evidence from Brazil Payroll Loans

A large body of literature has stressed the institution-development nexus as critical in explaining differences in countries' economic performance. The empirical evidence, however, has been mainly at the aggregate level, associating macro performance with measures of quality of institutions. This paper, by relating a judicial decision on the legality of payroll debit loans in Brazil to bank-level decision variables, provides micro evidence on how creditor legal protection affects market performance. Payroll loans are personal loans with principal and interests payments directly deducted from the borrowers' payroll check, which, in practice, makes a collateral out of future income. In June 2004, a high-level federal court upheld a regional court ruling that had declared payroll deduction illegal. Using personal loans without payroll deduction as a control group, we assess whether the ruling had an impact on market performance. Evidence indicates that it had an adverse impact on risk perception, interest rates, and amount lent.

The effect of the availability of student credit on tuition: testing the Bennett hypothesis using evidence from a large-scale student loan program in Brazil

Exploring the expansion of FIES—a large student lending program in Brazil— we test whether eligibility for subsidized student lending causes tuition to rise, in accordance with the Bennett hypothesis. FIES rules created arguably exogenous variation in eligibility across different majors and higher education institutions, which we exploit in a difference-indifferences framework. Using unique information on tuition, we document that FIES eligibility caused tuition to rise. We then estimate a structural demand model to explore whether a reduction in the sensitivity of demand to price increases is one of the possible mechanisms behind this credit-driven tuition rise. Our results show that FIES expansion is associated with a reduction in the tuition elasticity of demand

AdS_4/CFT_3 Construction from Collective Fields

We pursue the construction of higher-spin theory in AdS_4 from CFT_3 of the O(N) vector model in terms of canonical collective fields. In null plane quantization an exact map is established between the two spaces. The coordinates of the AdS_4 space-time are generated from the collective coordinates of the bi-local field. This, in the light cone gauge, provides an exact one to one reconstruction of bulk AdS_4 space-time and higher-spin fields.Comment: 17 pages, no figures; v2: references added; v3: minor change

Solving Four Dimensional Field Theories with the Dirichlet Fivebrane

The realization of ${\cal N}=2$ four dimensional super Yang-Mills theories in terms of a single Dirichlet fivebrane in type IIB string theory is considered. A classical brane computation reproduces the full quantum low energy effective action. This result has a simple explanation in terms of mirror symmetry.Comment: Final version to appear in Phys. Rev.

Evaluation Of Glueball Masses From Supergravity

In the framework of the conjectured duality relation between large $N$ gauge theory and supergravity the spectra of masses in large $N$ gauge theory can be determined by solving certain eigenvalue problems in supergravity. In this paper we study the eigenmass problem given by Witten as a possible approximation for masses in QCD without supersymmetry. We place a particular emphasis on the treatment of the horizon and related boundary conditions. We construct exact expressions for the analytic expansions of the wave functions both at the horizon and at infinity and show that requiring smoothness at the horizon and normalizability gives a well defined eigenvalue problem. We show for example that there are no smooth solutions with vanishing derivative at the horizon. The mass eigenvalues up to $m^{2}=1000$ corresponding to smooth normalizable wave functions are presented. We comment on the relation of our work with the results found in a recent paper by Cs\'aki et al., hep-th/9806021, which addresses the same problem.Comment: 20 pages,Latex,3 figs,psfig.tex, added refs., minor change

The impact of polymorphic variations in the 5p15, 6p12, 6p21 and 15q25 loci on the risk and prognosis of Portuguese patients with non-small cell lung cancer

Polymorphic variants in the 5p15, 6p12, 6p21, and 15q25 loci were demonstrated to potentially contribute to lung cancer carcinogenesis. Therefore, this study was performed to assess the role of those variants in non-small cell lung cancer (NSCLC) risk and prognosis in a Portuguese population. MATERIALS AND METHODS: Blood from patients with NSCLC was prospectively collected. To perform an association study, DNA from these patients and healthy controls were genotyped for a panel of 19 SNPs using a Sequenom® MassARRAY platform. Kaplan-Meier curves were used to assess the overall survival (OS) and progression-free survival (PFS). RESULTS: One hundred and forty-four patients with NSCLC were successfully consecutively genotyped for the 19 SNPs. One SNP was associated with NSCLC risk: rs9295740 G/A. Two SNPs were associated with non-squamous histology: rs3024994 (VEGF intron 2) T/C and rs401681 C/T. Three SNPs were associated with response rate: rs3025035 (VEGF intron 7) C/T, rs833061 (VEGF -460) C/T and rs9295740 G/A. One SNP demonstrated an influence on PFS: rs401681 C/T at 5p15, p?=?0.021. Four SNPs demonstrated an influence on OS: rs2010963 (VEGF +405 G/C), p?=?0.042; rs3025010 (VEGF intron 5 C/T), p?=?0.047; rs401681 C/T at 5p15, p?=?0.046; and rs31489 C/A at 5p15, p?=?0.029. CONCLUSIONS: Our study suggests that SNPs in the 6p12, 6p21, and 5p15 loci may serve as risk, predictive and prognostic NSCLC biomarkers. In the future, SNPs identified in the genomes of patients may improve NSCLC screening strategies and therapeutic management as well.This project was supported by Programa Doutoral em Medicina e Oncologia Molecular, University of Porto, Porto, Portugal and University of Minho, Braga, Portugal. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Systematic 1/N1/N corrections for bosonic and fermionic vector models without auxiliary fields

In this paper, colorless bilocal fields are employed to study the large $N$ limit of both fermionic and bosonic vector models. The Jacobian associated with the change of variables from the original fields to the bilocals is computed exactly, thereby providing an exact effective action. This effective action is shown to reproduce the familiar perturbative expansion for the two and four point functions. In particular, in the case of fermionic vector models, the effective action correctly accounts for the Fermi statistics. The theory is also studied non-perturbatively. The stationary points of the effective action are shown to provide the usual large $N$ gap equations. The homogeneous equation associated with the quadratic (in the bilocals) action is simply the two particle Bethe Salpeter equation. Finally, the leading correction in $1\over N$ is shown to be in agreement with the exact $S$ matrix of the model.Comment: 24 pages, uses REVTEX macros. Replaced with final version to appear in Phys. Rev.

Non-holomorphic Corrections from Threebranes in F Theory

We construct solutions of type IIB supergravity dual to N=2 super Yang-Mills theories. By considering a probe moving in a background with constant coupling and an AdS_{5} component in its geometry, we are able to reproduce the exact low energy effective action for the theory with gauge group SU(2) and N_{f}=4 massless flavors. After turning on a mass for the flavors we find corrections to the AdS_{5} geometry. In addition, the coupling shows a power law dependence on the energy scale of the theory. The origin of the power law behaviour of the coupling is traced back to instanton corrections. Instanton corrections to the four derivative terms in the low energy effective action are correctly obtained from a probe analysis. By considering a Wilson loop in this geometry we are also able to compute the instanton effects on the quark-antiquark potential. Finally we consider a solution corresponding to an asymptotically free field theory. Again, the leading form of the four derivative terms in the low energy effective action are in complete agreement with field theory expectations.Comment: 23 pages, uses harvmac, References added, typos corrected and minor improvements to discussion of N dependence, to appear in Phys. Rev.