College Education and Wages in the U.K.: Estimating Conditional Average Structural Functions in Nonadditive Models with Binary Endogenous Variables

Recent studies debate how the unobserved dependence between the monetary return to college education and selection into college can be characterized. This paper examines this question using British data. We develop a semiparametric local instrumental variables estimator for identified features of a flexible correlated random coefficient model. These identified features are directly related to the marginal and average treatment effect in policy evaluation. Our results indicate that returns to college systematically differ between actual college graduates and actual college non-graduates. They are on average higher for college graduates and positively related to selection into college for 96 percent of the individuals. The dependence between selection into college and returns to college education is strongest for individuals with low math test scores at the age of 7, individuals with less educated mothers, and for working-class individuals.Returns to college education;correlated random coefficient model;local instrumental variables estimation

Returns to Type or Tenure?

A regression of wages on firm tenure is likely to yield biased estimates of the returns to tenure because tenure and wages are confounded by unobserved attributes of the job and the unobserved quality of the match between the firm and the employee. Previously, the within-job variation in tenure has been used as an instrument to estimate the average returns to tenure. In this paper, we propose to use instead an easy-to-implement control function estimator for the returns to tenure and their dependence on unobserved heterogeneity. The obtained results for Germany indicate that there is a substantial amount of unobserved heterogeneity in the returns to tenure and that good job matches are characterized by higher returns to tenure in the first five years and lower returns thereafter.Wage growth;returns to tenure;selection on unobservables;control function approach;nonseparable model

Assessing Unilateral Merger Effects in a Two-Sided Market: An Application to the Dutch Daily Newspaper Market

We compare different methods to assess unilateral merger effects in a two-sided market by applying them to a hypothetical merger in the Dutch newspaper industry. For this, we first specify and estimate a structural model of demand for differentiated products on both the readership and the advertising side of the market. This allows us to recover price elasticities and indirect network effects. Following Filistrucchi, Klein, and Michielsen (2010) marginal costs are then recovered from an oligopoly model of the supply side. We use these estimates of price elasticities, network effects and marginal costs to compare different methods that can be used to evaluate merger effects: We perform a concentration analysis based on the Herfindahl Hirschmann Index, a Small Significant Non-Transitory Increase in Price test, measure Upward Pricing Pressure, and conduct a full merger simulation.Two-sided markets;newspapers;advertising;network effects;merger simulation;SSNIP;UPP;HHI

FISH mapping and molecular organization of the major repetitive sequences of tomato

This paper presents a bird's-eye view of the major repeats and chromatin types of tomato. Using fluorescence in-situ hybridization (FISH) with Cot-1, Cot-10 and Cot-100 DNA as probes we mapped repetitive sequences of different complexity on pachytene complements. Cot-100 was found to cover all heterochromatin regions, and could be used to identify repeat-rich clones in BAC filter hybridization. Next we established the chromosomal locations of the tandem and dispersed repeats with respect to euchromatin, nucleolar organizer regions (NORs), heterochromatin, and centromeres. The tomato genomic repeats TGRII and TGRIII appeared to be major components of the pericentromeres, whereas the newly discovered TGRIV repeat was found mainly in the structural centromeres. The highly methylated NOR of chromosome 2 is rich in [GACA](4), a microsatellite that also forms part of the pericentromeres, together with [GA](8), [GATA](4) and Ty1-copia. Based on the morphology of pachytene chromosomes and the distribution of repeats studied so far, we now propose six different chromatin classes for tomato: (1) euchromatin, (2) chromomeres, (3) distal heterochromatin and interstitial heterochromatic knobs, (4) pericentromere heterochromatin, (5) functional centromere heterochromatin and (6) nucleolar organizer regio

Characterization of a Li-6 loaded liquid organic scintillator for fast neutron spectrometry and thermal neutron detection

The characterization of a liquid scintillator incorporating an aqueous solution of enriched lithium chloride to produce a scintillator with 0.40% Li-6 is presented, including the performance of the scintillator in terms of its optical properties and neutron response. The scintillator was incorporated into a fast neutron spectrometer, and the light output spectra from 2.5 MeV, 14.1 MeV, and Cf-252 neutrons were measured using capture-gated coincidence techniques. The spectrometer was operated without coincidence to perform thermal neutron measurements. Possible improvements in spectrometer performance are discussed.Comment: Submitted to Applied Radiation and Isotopes. 11 pages, 7 figures, 3 tables. Revision addresses reviewers' comment

Statistical analysis of nitrous oxide emission factors from pastoral agriculture field trials conducted in New Zealand

AbstractBetween 11 May 2000 and 31 January 2013, 185 field trials were conducted across New Zealand to measure the direct nitrous oxide (N2O) emission factors (EF) from nitrogen (N) sources applied to pastoral soils. The log(EF) data were analysed statistically using a restricted maximum likelihood (REML) method. To estimate mean EF values for each N source, best linear unbiased predictors (BLUPs) were calculated. For lowland soils, mean EFs for dairy cattle urine and dung, sheep urine and dung and urea fertiliser were 1.16 ± 0.19% and 0.23 ± 0.05%, 0.55 ± 0.19% and 0.08 ± 0.02% and 0.48 ± 0.13%, respectively, each significantly different from one another (p < 0.05), except for sheep urine and urea fertiliser. For soils in terrain with slopes >12°, mean EFs were significantly lower. Thus, urine and dung EFs should be disaggregated for sheep and cattle as well as accounting for terrain

A MapReduce Framework for Analysing Portfolios of Catastrophic Risk with Secondary Uncertainty

AbstractThe design and implementation of an extensible framework for performing exploratory analysis of complex property portfolios of catastrophe insurance treaties on the Map-Reduce model is presented in this paper. The framework implements Aggregate Risk Analysis, a Monte Carlo simulation technique, which is at the heart of the analytical pipeline of the modern quantitative insurance/reinsurance pipeline. A key feature of the framework is the support for layering advanced types of analysis, such as portfolio or program level aggregate risk analysis with secondary uncertainty (i.e. computing Probable Maximum Loss (PML) based on a distribution rather than mean values). Such in-depth analysis is not supported by production-based risk management systems since they are constrained by hard response time requirements placed on them. On the other hand, this paper reports preliminary experimental results to demonstrate that in-depth aggregate risk analysis can be realized using a framework based on the MapReduce model