Systematic analysis of the impact of label noise correction on ML Fairness

Arbitrary, inconsistent, or faulty decision-making raises serious concerns, and preventing unfair models is an increasingly important challenge in Machine Learning. Data often reflect past discriminatory behavior, and models trained on such data may reflect bias on sensitive attributes, such as gender, race, or age. One approach to developing fair models is to preprocess the training data to remove the underlying biases while preserving the relevant information, for example, by correcting biased labels. While multiple label noise correction methods are available, the information about their behavior in identifying discrimination is very limited. In this work, we develop an empirical methodology to systematically evaluate the effectiveness of label noise correction techniques in ensuring the fairness of models trained on biased datasets. Our methodology involves manipulating the amount of label noise and can be used with fairness benchmarks but also with standard ML datasets. We apply the methodology to analyze six label noise correction methods according to several fairness metrics on standard OpenML datasets. Our results suggest that the Hybrid Label Noise Correction method achieves the best trade-off between predictive performance and fairness. Clustering-Based Correction can reduce discrimination the most, however, at the cost of lower predictive performance

DO DYNAMIC TARIFFS PROMOTE INVESTMENT IN RENEWABLES? THE CASE OF A NON-REGULATED MONOPOLY

We consider a non-regulated monopolist supplier of electricity that may use renewable and/or non-renewable resources to produce electricity. Renewable resources require an ex ante investment and generate an uncertain output with fixed operating costs. Non-renewable resources are perfectly dispatchable and have variable operating costs proportional to output. We find that dynamic tariffs promote investment in renewables in all scenarios except one where output from renewables when weather conditions are favorable is so large that the monopolist prefers to curtail excess energy. Only in that scenario, dynamic tariffs decrease investment in renewables. In any case, dynamic tariffs are welfare-improving in that both the monopolist and consumers become better off

Perdas de mamão (Carica papaya L.) comercializado no Estado do Rio de Janeiro.

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The use of visible and near infrared reflectance spectroscopy to predict beef M. longissimus thoracis et lumborum quality attributes

Visible and near infrared reflectance spectroscopy was used to predict pH at 24 h (pH24) post-mortem, sarcomere length (SL), cooking loss (CL), Warner–Bratzler Shear Force (WBSF) and colour parameters (L*, a*, b*) in beef cattle samples. Samples from M. longissimus thoracis et lumborum from 30 bulls were aged at 4 C for 1, 3, 7 and 14 days and analysed for pH, SL, CL, WBSF and colour. NIRS calibrations for pH24, luminosity at 0 (L*t0) and 60 min (L*t60) showed good predictability (R2 = 0.97, 0.85 and 0.82; SECV = 0.10, 1.16, 1.36, respectively), whereas those related to the rest of the parameters were poore

On assessment of processing variables on vertical centrifugal casting technique

The aim of the present study is to investigate the influence of the vertical centrifugal casting technique over mechanical and metallurgical properties of a hypereutectic Al–18Si alloy. Due to the inherent vibration of the centrifugal casting technique, and in order to study and understand the individual effects of the equipment vibration and the centrifugal force itself (pressure or fluid dynamics), as well as the combined effect of both, three different tests were performed: gravity casting, gravity casting with vibration and centrifugal casting. It was concluded that the metallurgical and mechanical properties of castings obtained by the centrifugal casting process depend on the combined effect of the centrifugal pressure and/or fluid dynamics and on the inherent vibration of the technique itself. Correlations between the different casting techniques and obtained mechanical and metallurgical properties are presentedFCT - Fundação para a Ciência e Tecnologi

Morphogenesis of Marandu Brachiaria Under Different Nitrogen Rates in the Brazilian Savannah

Nitrogen fertilization contributes to grass growth and, for this reason, the objective was to evaluate the morphogenic characteristics of Urochloa brizantha cultivar Marandu subjected to different nitrogen rates (0, 50, 100 and 150 kg N.ha-1) in the Brazilian savannah through the variables number of leaves.tiller-1, leaf growth, leaf average size, senescent leaf.tiller-1 number and stem+pseudostem average size. The experiment was established in the Forage and Pastures Sector of Jatai Federal University (UFJ) and, after the soil correction and fertilization, the Marandu grass plots were installed in a randomized blocks experimental design, with four treatments and four replications. When the forage canopy reached the cutting height (30 cm) it was homogenized with pruning shears and four tillers per plot were identified with colored tape and a locating stake. Morphogenesis data was collected every two days, measuring the leaves size and stem+pseudostem size, and leaves were classifying according to their physiological state. Marandu cultivar showed increasing response in leaves number and in leaf growth in nitrogen doses from 50 to 100 kg N.ha-1. The number of senescent leaf.tiller-1 decrease when nitrogen fertilization increase from 0 to 100 kg N.ha-1. Marandu showed a morphogenic response to nitrogen fertilization and up to 100 kg N.ha-1 can be used

Observation of environment-induced double sudden transitions in geometric quantum correlations

Correlations in quantum systems exhibit a rich phenomenology under the effect of various sources of noise. We investigate theoretically and experimentally the dynamics of quantum correlations and their classical counterparts in two nuclear magnetic resonance setups, as measured by geometric quantifiers based on trace-norm. We consider two-qubit systems prepared in Bell diagonal states, and perform the experiments in decohering environments resulting from Bell diagonal-preserving Markovian local noise. We then report the first observation of environment-induced double sudden transitions in the geometric quantum correlations, a genuinely nonclassical effect not observable in classical correlations. The evolution of classical correlations in our physical implementation reveals in turn the finite-time relaxation to a pointer basis under nondissipative decoherence, which we characterize geometrically in full analogy with predictions based on entropic measures.Comment: 5 pages, 2 figures. v2: Minor corrections. Published versio

Early family adversity, stability and consistency of institutional care and infant cognitive, language and motor development across the first six months of institutionalization

This study extends research on the effects of institutionalization—by examining the trajectories of cognitive, language and motor development of 64 Portuguese infants and toddlers across the first six months of institutionalization, while determining whether pre-institutional adversities and the stability and consistency of institutional care predict children’s development. At time of enrollment, 23.4%, 32.8% and 31.3% of the children were moderately to severely delayed, respectively, in their cognitive, linguistic and motor functioning. Developmental problems persisted after six months of institutionalization. The accumulation of early pre-institutional adversities predicted cognitive and motor limitations at admission to the institutions, but not variation in subsequent development. The stability and consistency of institutional care also failed to predict developmental growth and change. Children who had never lived with their families of origin showed a better language development at enrollment than their counterparts who had lived with their families of origin before institutionalization. Such advantage was followed by a deceleration in language growth after six months of institutional placement. Results are discussed in terms of short- vs. longer-term effects of institutionalization.info:eu-repo/semantics/acceptedVersio