Family Background, Self-Confidence and Economic Outcomes

In this paper we analyze the role played by self-confidence, modeled as beliefs about one's ability, in shaping task choices. We propose a model in which fully rational agents exploit all the available information to update their beliefs using Bayes' rule, eventually learning their true type. We show that when the learning process does not convergence quickly to the true ability level, even small differences in initial confidence can result in diverging patterns of human capital accumulation between otherwise identical individuals. As long as inital differences in the level of self-confidence are correlated with the socioeconomic background (as a large body of empirical evidence suggests), self-confidence turns out to be a channel through which education and earnings inequalities are transmitted across generations. Our theory suggests that cognitive tests should take place as early as possible, in order to avoid that systematic differences in self-confidence among equally talented people lead to the emergence of gaps in the accumulation of human capital.self-confidence, family background

Evaluating students' evaluations of professors

This paper contrasts measures of teacher effectiveness with the students’ evaluations of the same teachers using administrative data from Bocconi University (Italy). The effectiveness measures are estimated by comparing the subsequent performance in follow-on coursework of students who are randomly assigned to teachers in each of their compulsory courses. We find that, even in a setting where the syllabuses are fixed, teachers still matter substantially. Additionally, we find that our measure of teacher effectiveness is negatively correlated with the students’ evaluations of professors: in other words, teachers who are associated with better subsequent performance receive worse evaluations from their students. We rationalize these results with a simple model where teachers can either engage in real teaching or in teaching-to-the-test, the former requiring greater student effort than the latter. Teaching-to-the-test guarantees high grades in the current course but does not improve future outcomes. Hence, if students are short-sighted and give better evaluations to teachers from whom they derive higher utility in a static framework, the model is capable of predicting our empirical finding that good teachers receive bad evaluations.teacher quality, postsecondary education

Evaluating Students' Evaluations of Professors

This paper contrasts measures of teacher effectiveness with the students' evaluations for the same teachers using administrative data from Bocconi University (Italy). The effectiveness measures are estimated by comparing the subsequent performance in follow-on coursework of students who are randomly assigned to teachers in each of their compulsory courses. We find that, even in a setting where the syllabuses are fixed and all teachers in the same course present exactly the same material, teachers still matter substantially. The average difference in subsequent performance between students who were assigned to the best and worst teacher (on the effectiveness scale) is approximately 43% of a standard deviation in the distribution of exam grades, corresponding to about 5.6% of the average grade. Additionally, we find that our measure of teacher effectiveness is negatively correlated with the students' evaluations: in other words, teachers who are associated with better subsequent performance receive worst evaluations from their students. We rationalize these results with a simple model where teachers can either engage in real teaching or in teaching-to-the-test, the former requiring higher students’ effort than the latter. Teaching-to-the-test guarantees high grades in the current course but does not improve future outcomes. Hence, if students are myopic and evaluate better teachers from which they derive higher utility in a static framework, the model is capable of predicting our empirical finding that good teachers receive bad evaluations, especially when teaching-to-the-test is very effective (for example, with multiple choice tests). Consistently with the predictions of the model, we also find that classes in which high skill students are over-represented produce evaluations that are less at odds with estimated teacher effectiveness.teacher quality, postsecondary education

Literacy and Numeracy Proficiency in IALS, ALL and PIAAC

This paper analyses proficiency in literacy and numeracy in the countries that have participated in the International Adult Literacy Survey (IALS, administered between 1994 and 1998), the Adult Literacy and Life Skills Survey (ALL, administered between 2003 and 2007) and the Survey of Adult Skills (PIAAC, administered in 2012). While many countries experienced small to modest changes in literacy proficiency between IALS and PIAAC, others saw sizeable variations, mostly on the negative side. In the shorter span that separated ALL and PIAAC, numeracy proficiency clearly declined (except in Italy), while literacy moved less on average (except for the large increase registered in Italy and the large decline experienced by Norway). Changes in the composition of the population have had little impact on observed changes in scores. Larger variations took place within different socio-demographic groups, but these tended to cancel each other out on aggregate. In particular, large variations are observed by age and levels of education. Older adults in PIAAC are generally more proficient than their IALS counterparts, probably due to the increase in educational attainments that took place over recent decades. On the contrary, tertiary-educated individuals appear to be on average less proficient than in the past, which may signal that the expansion of tertiary education has been accompanied by a decline in the average quality of university graduates (or of university instruction). There is also no evidence that the change in delivery mode, with a switch to a computer-based assessment in PIAAC, had any significant effect on performance. However, the OECD is unable to ascertain how differences in implementation and technical standards affect the comparability of the data, so that a certain degree of caution should always be exercised in interpreting these results. Amongst the countries that experienced larger changes in literacy proficiency between surveys, a close inspection of IALS data (in particular through an investigation of response patterns at the item level) highlights some anomalies in Italy and Poland (and, to a lesser extent, in England and Northern Ireland), suggesting that particular caution should be exercised in interpreting the evolution of proficiency in these countries

inkjet sensors produced by consumer printers with smartphone impedance readout

Abstract Inkjet printing technology is showing a disruptive potential for low-cost optical and electrochemical biosensors fabrication. This technology is becoming affordable for every laboratory, potentially allowing every research group to implement a biosensors fabrication platform with consumer inkjet printers, commercially available inks and smartphones for readout. In the present work we developed an example of such platform testing several inks, printers, and substrates. We defined and optimized the protocols assessing the printing limits and the fabricated biosensors electrochemical properties in standard solutions. Our platform has a total cost of less than 450 Euro and a single sensor fabrication cost of 0.026 Euro. Finally, we tested the sensitivity of smartphone-performed impedance measurements with printed biosensors surface coverage by Self Assembling Monolayers (SAM), validating them with standard instruments

The strong correlation between post-starburst fraction and environment

We examine a magnitude limited (MB ≤ -18.7) sample of post-starburst (PSB) galaxies at 0.03 < z < 0.11 in the different environments from the spectroscopic data set of the Padova Millennium Galaxy Group Catalogue and compare their incidence and properties with those of passive (PAS) and emission line galaxies (EML). PSB galaxies have a quite precise lifetime (<1-1.5 Gyr), and they hold important clues for understanding galaxy evolution. While the properties (stellar mass, absolute magnitude, colour) of PSBs do not depend on environment, their frequency increases going from single galaxies to binary systems to groups, both considering the incidence with respect to the global number of galaxies and to the number of currently+recently star-forming galaxies. Including in our analysis, the sample of cluster PSBs drawn from the WIde-field Nearby Galaxy-cluster Survey presented in Paccagnella et al., we extend the halo mass range covered and present a coherent picture of the effect of the environment on galaxy transformations. We find that the PSB/(PSB + EML) fraction steadily increases with halo mass going from 1 per cent in 10^{11} M_{☉} haloes to ∼15 per cent in the most massive haloes (10^{15.5} M_{☉}). This provides evidence that processes specific to the densest environments, such as ram-pressure stripping, are responsible for a large fraction of PSB galaxies in dense environments. These processes act on a larger fraction of galaxies than alternative processes leading to PSB galaxies in the sparsest environments, such as galaxy interactions

Possible effects on avionics induced by terrestrial gamma-ray flashes

Abstract. Terrestrial gamma-ray flashes (TGFs) are impulsive (intrinsically sub-millisecond) events associated with lightning in powerful thunderstorms. TGFs turn out to be very powerful natural accelerators known to accelerate particles and generate radiation up to hundreds of MeV energies. The number ratio of TGFs over normal lightning has been measured in tropical regions to be near 10−4. We address in this Article the issue of the possible susceptibility of typical aircraft electronics exposed to TGF particle, gamma ray and neutron irradiation. We consider possible scenarios regarding the intensity, the duration, and geometry of TGFs influencing nearby aircraft, and study their effects on electronic equipment. We calculate, for different assumptions, the total dose and the dose-rate, and estimate single-event-effects. We find that in addition to the electromagnetic component (electrons/positrons, gamma rays) also secondary neutrons produced by gamma-ray photo production in the aircraft structure substantially contribute to single-event effects in critical semiconductors components. Depending on the physical characteristics and geometry, TGFs may deliver a large flux of neutrons within a few milliseconds in an aircraft. This flux is calculated to be orders of magnitude larger than the natural cosmic-ray background, and may constitute a serious hazard to aircraft electronic equipment. We present a series of numerical simulations supporting our conclusions. Our results suggest the necessity of dedicated measurement campaigns addressing the radiative and particle environment of aircraft near or within thunderstorms

VizieR Online Data Catalog: OmegaWINGS local clusters of galaxies redshifts (Moretti+, 2017)

Redshifts, magnitude/radial completeness, and memberships are given for the 17985 galaxies observed as part of the OmegaWINGS survey of local clusters of galaxies over 1 square degree. Redshifts have been measured using both absorption and emission lines features. The sample magnitude completeness is 80% at V=20. Thanks to the observing strategy, the radial completeness turned out to be relatively constant (90%) within the AAOmega field of view. The success rate in measuring redshifts is 95%, at all radii. Cluster members are flagged 1 or 2, depending on the cluster structure/secondary structure, and 0 if they are not cluster members. (1 data file)

Erratum: “GASP. I. Gas Stripping Phenomena in Galaxies with MUSE” (2017, ApJ, 844, 48)

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