Undesirable biases in NLP: Averting a crisis of measurement

As Natural Language Processing (NLP) technology rapidly develops and spreads into daily life, it becomes crucial to anticipate how its use could harm people. However, our ways of assessing the biases of NLP models have not kept up. While especially the detection of English gender bias in such models has enjoyed increasing research attention, many of the measures face serious problems, as it is often unclear what they actually measure and how much they are subject to measurement error. In this paper, we provide an interdisciplinary approach to discussing the issue of NLP model bias by adopting the lens of psychometrics -- a field specialized in the measurement of concepts like bias that are not directly observable. We pair an introduction of relevant psychometric concepts with a discussion of how they could be used to evaluate and improve bias measures. We also argue that adopting psychometric vocabulary and methodology can make NLP bias research more efficient and transparent

Multidifferential study of identified charged hadron distributions in ZZ-tagged jets in proton-proton collisions at s=\sqrt{s}=13 TeV

Jet fragmentation functions are measured for the first time in proton-proton collisions for charged pions, kaons, and protons within jets recoiling against a $Z$ boson. The charged-hadron distributions are studied longitudinally and transversely to the jet direction for jets with transverse momentum 20 $< p_{\textrm{T}} < 100$ GeV and in the pseudorapidity range $2.5 < \eta < 4$. The data sample was collected with the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 1.64 fb$^{-1}$. Triple differential distributions as a function of the hadron longitudinal momentum fraction, hadron transverse momentum, and jet transverse momentum are also measured for the first time. This helps constrain transverse-momentum-dependent fragmentation functions. Differences in the shapes and magnitudes of the measured distributions for the different hadron species provide insights into the hadronization process for jets predominantly initiated by light quarks.Comment: All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-013.html (LHCb public pages

Study of the B−→Λc+Λˉc−K−B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-} decay

The decay $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ is studied in proton-proton collisions at a center-of-mass energy of $\sqrt{s}=13$ TeV using data corresponding to an integrated luminosity of 5 $\mathrm{fb}^{-1}$ collected by the LHCb experiment. In the $\Lambda_{c}^+ K^{-}$ system, the $\Xi_{c}(2930)^{0}$ state observed at the BaBar and Belle experiments is resolved into two narrower states, $\Xi_{c}(2923)^{0}$ and $\Xi_{c}(2939)^{0}$, whose masses and widths are measured to be $$m(\Xi_{c}(2923)^{0}) = 2924.5 \pm 0.4 \pm 1.1 \,\mathrm{MeV}, \\ m(\Xi_{c}(2939)^{0}) = 2938.5 \pm 0.9 \pm 2.3 \,\mathrm{MeV}, \\ \Gamma(\Xi_{c}(2923)^{0}) = \phantom{000}4.8 \pm 0.9 \pm 1.5 \,\mathrm{MeV},\\ \Gamma(\Xi_{c}(2939)^{0}) = \phantom{00}11.0 \pm 1.9 \pm 7.5 \,\mathrm{MeV},$$ where the first uncertainties are statistical and the second systematic. The results are consistent with a previous LHCb measurement using a prompt $\Lambda_{c}^{+} K^{-}$ sample. Evidence of a new $\Xi_{c}(2880)^{0}$ state is found with a local significance of $3.8\,\sigma$, whose mass and width are measured to be $2881.8 \pm 3.1 \pm 8.5\,\mathrm{MeV}$ and $12.4 \pm 5.3 \pm 5.8 \,\mathrm{MeV}$, respectively. In addition, evidence of a new decay mode $\Xi_{c}(2790)^{0} \to \Lambda_{c}^{+} K^{-}$ is found with a significance of $3.7\,\sigma$. The relative branching fraction of $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ with respect to the $B^{-} \to D^{+} D^{-} K^{-}$ decay is measured to be $2.36 \pm 0.11 \pm 0.22 \pm 0.25$, where the first uncertainty is statistical, the second systematic and the third originates from the branching fractions of charm hadron decays.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-028.html (LHCb public pages

Measurement of the ratios of branching fractions R(D∗)\mathcal{R}(D^{*}) and R(D0)\mathcal{R}(D^{0})

The ratios of branching fractions $\mathcal{R}(D^{*})\equiv\mathcal{B}(\bar{B}\to D^{*}\tau^{-}\bar{\nu}_{\tau})/\mathcal{B}(\bar{B}\to D^{*}\mu^{-}\bar{\nu}_{\mu})$ and $\mathcal{R}(D^{0})\equiv\mathcal{B}(B^{-}\to D^{0}\tau^{-}\bar{\nu}_{\tau})/\mathcal{B}(B^{-}\to D^{0}\mu^{-}\bar{\nu}_{\mu})$ are measured, assuming isospin symmetry, using a sample of proton-proton collision data corresponding to 3.0 fb${ }^{-1}$ of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode $\tau^{-}\to\mu^{-}\nu_{\tau}\bar{\nu}_{\mu}$. The measured values are $\mathcal{R}(D^{*})=0.281\pm0.018\pm0.024$ and $\mathcal{R}(D^{0})=0.441\pm0.060\pm0.066$, where the first uncertainty is statistical and the second is systematic. The correlation between these measurements is $\rho=-0.43$. Results are consistent with the current average of these quantities and are at a combined 1.9 standard deviations from the predictions based on lepton flavor universality in the Standard Model.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-039.html (LHCb public pages

Melt and fluid evolution in an upper-crustal magma reservoir, preserved by inclusions in juvenile clasts from the Kos Plateau Tuff, Aegean Arc, Greece

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Evolution from magmatic to hydrothermal activity beneath the Cerro Escorial volcano (NW Argentina) as sampled by erupted quartz and brines

Large quartz pebbles erupted with the Escorial ignimbrite provide insight into the late-magmatic evolution of the shallow, cooling magmatic-hydrothermal system below the Cerro Escorial volcano of the Southern Central Volcanic Zone in the Argentine Andes. The ignimbrite is of relatively small volume, crystal-rich, dacitic in composition, and not particularly water-rich, as amphibole is absent. Eruption temperature was estimated to be close to 850 °C. The quartz pebbles provide insight into the magmatic-hydrothermal transition beneath the volcano. Based on textures, trace element composition (analyzed by laser-ablation inductively-coupled plasma mass spectrometry), and inclusion content, the pebbles can be separated into pegmatite-like megacrysts and lower-temperature, epithermal microcrystalline quartz. Both types are distinct from magmatic phenocrysts present in porphyritic clasts ejected by the ignimbrite. The megacrysts show a wide range of trace element concentrations, with elevated Al concentrations and Al/Ti and Ge/Ti ratios compared to quartz phenocrysts. Although some contamination by submicroscopic inclusions and cooling to near-solidus temperatures may perturb the signal in some cases, the range of trace element concentrations in quartz crystals from this system may reflect a change in crystallization conditions from initial precipitation from typical evolved silicate melt to fast growth from residual melt and/or fluid in pegmatitic pockets or coarse-grained hydrothermal “veins” at locally variable precipitation conditions. Abundant primary and secondary silicate melt inclusions and a variety of secondary fluid inclusions are present within the megacrysts. In particular, brine inclusions are densely packed with salt crystals, sometimes anhydrite and/or a silicate crystal, but no visible liquid at room temperature, and co-existing vapor inclusions are of very low density. Heating experiments of brine inclusions reveal last salt and vapor bubble dissolution temperatures around 600–700 °C, but an immiscible silicate melt surrounding the homogenized salt globule remains even at unreasonably high temperature. The co-existence of silicate melt and fluid inclusions reinforces the magmatic nature of the fluids, while boiling trails of brine (with Cu concentrations of several percent) and vapor point to relatively low pressures (<100 MPa). © 2020 Elsevier B.V.ISSN:0024-493

Melt and fluid evolution in an upper-crustal magma reservoir, preserved by inclusions in juvenile clasts from the Kos Plateau Tuff, Aegean Arc, Greece

ISSN:0016-7037ISSN:1872-953