言語理解研究における眼球運動データ及び読み時間データの統計分析

要旨あり統計的言語研究の現在原著論

A Subjective Comparison Between a Historical and a Contemporary Textbook on Geometry

In order to investigate how a 19th century mathematical textbook (in contrast to a contemporary one) would be experienced by a novice reader, we embarked on the following project: In the summer of 2013, a student with no previous training in college-level mathematics (the first author) set out to learn projective geometry from Pasch\u27s 1882 textbook Lectures on Modern Geometry. Afterwards, he studied the same material from Coxeter\u27s 1994 popular undergraduate textbook Projective Geometry. We report here some of his experiences and impressions contextualizing them along the way

ESTIMATING EXTERNAL COSTS OF MUNICIPAL LANDFILL SITING THROUGH CONTINGENT VALUATION ANALYSIS: A CASE STUDY

Much of the solid waste stream in the United States is generated by metropolitan areas, while associated landfills are often located in adjacent rural communities. Landfill disposal of municipal solid waste often creates external costs to nearby residents. Contingent valuation was used to estimate external costs of siting a landfill in the Carter community of Knox County, Tennessee. Estimates of annual external costs were $227 per household. Household income, size, years in the community, and distance from the proposed landfill and the respondent's education, sex, and perception of health risks were important in determining a household's willingness to pay to avoid having a landfill in the Carter community. Also, households whose drinking water supplies were at risk of contamination were willing to pay$141 more than those who used piped city water or bottled water.Public Economics,

A three-state model with loop entropy for the over-stretching transition of DNA

We introduce a three-state model for a single DNA chain under tension that distinguishes between B-DNA, S-DNA and M (molten or denatured) segments and at the same time correctly accounts for the entropy of molten loops, characterized by the exponent c in the asymptotic expression S ~ - c ln n for the entropy of a loop of length n. Force extension curves are derived exactly employing a generalized Poland-Scheraga approach and compared to experimental data. Simultaneous fitting to force-extension data at room temperature and to the denaturation phase transition at zero force is possible and allows to establish a global phase diagram in the force-temperature plane. Under a stretching force, the effects of the stacking energy, entering as a domain-wall energy between paired and unpaired bases, and the loop entropy are separated. Therefore we can estimate the loop exponent c independently from the precise value of the stacking energy. The fitted value for c is small, suggesting that nicks dominate the experimental force extension traces of natural DNA.Comment: 12 pages, 5 figures + Supplementary informatio

Depletion potentials in highly size-asymmetric binary hard-sphere mixtures: Comparison of accurate simulation results with theory

We report a detailed study, using state-of-the-art simulation and theoretical methods, of the depletion potential between a pair of big hard spheres immersed in a reservoir of much smaller hard spheres, the size disparity being measured by the ratio of diameters q=\sigma_s/\sigma_b. Small particles are treated grand canonically, their influence being parameterized in terms of their packing fraction in the reservoir, \eta_s^r. Two specialized Monte Carlo simulation schemes --the geometrical cluster algorithm, and staged particle insertion-- are deployed to obtain accurate depletion potentials for a number of combinations of q\leq 0.1 and \eta_s^r. After applying corrections for simulation finite-size effects, the depletion potentials are compared with the prediction of new density functional theory (DFT) calculations based on the insertion trick using the Rosenfeld functional and several subsequent modifications. While agreement between the DFT and simulation is generally good, significant discrepancies are evident at the largest reservoir packing fraction accessible to our simulation methods, namely \eta_s^r=0.35. These discrepancies are, however, small compared to those between simulation and the much poorer predictions of the Derjaguin approximation at this \eta_s^r. The recently proposed morphometric approximation performs better than Derjaguin but is somewhat poorer than DFT for the size ratios and small sphere packing fractions that we consider. The effective potentials from simulation, DFT and the morphometric approximation were used to compute the second virial coefficient B_2 as a function of \eta_s^r. Comparison of the results enables an assessment of the extent to which DFT can be expected to correctly predict the propensity towards fluid fluid phase separation in additive binary hard sphere mixtures with q\leq 0.1.Comment: 16 pages, 9 figures, revised treatment of morphometric approximation and reordered some materia

Accurate Structural Correlations from Maximum Likelihood Superpositions

The cores of globular proteins are densely packed, resulting in complicated networks of structural interactions. These interactions in turn give rise to dynamic structural correlations over a wide range of time scales. Accurate analysis of these complex correlations is crucial for understanding biomolecular mechanisms and for relating structure to function. Here we report a highly accurate technique for inferring the major modes of structural correlation in macromolecules using likelihood-based statistical analysis of sets of structures. This method is generally applicable to any ensemble of related molecules, including families of nuclear magnetic resonance (NMR) models, different crystal forms of a protein, and structural alignments of homologous proteins, as well as molecular dynamics trajectories. Dominant modes of structural correlation are determined using principal components analysis (PCA) of the maximum likelihood estimate of the correlation matrix. The correlations we identify are inherently independent of the statistical uncertainty and dynamic heterogeneity associated with the structural coordinates. We additionally present an easily interpretable method (“PCA plots”) for displaying these positional correlations by color-coding them onto a macromolecular structure. Maximum likelihood PCA of structural superpositions, and the structural PCA plots that illustrate the results, will facilitate the accurate determination of dynamic structural correlations analyzed in diverse fields of structural biology

Itinerant Nature of Atom-Magnetization Excitation by Tunneling Electrons

We have performed single-atom magnetization curve (SAMC) measurements and inelastic scanning tunneling spectroscopy (ISTS) on individual Fe atoms on a Cu(111) surface. The SAMCs show a broad distribution of magnetic moments with \unit[3.5]{\mu_{\rm B}} being the mean value. ISTS reveals a magnetization excitation with a lifetime of \unit[200]{fsec} which decreases by a factor of two upon application of a magnetic field of \unit[12]{T}. The experimental observations are quantitatively explained by the decay of the magnetization excitation into Stoner modes of the itinerant electron system as shown by newly developed theoretical modeling.Comment: 3 Figures, Supplement not included, updated version after revisio

Faculty Recital: Douglas Rubio, Classical Guitar & Roland GR-1 Guitar Synthesizer

Kemp Recital Hall Tuesday Evening March 1, 1994 8:00p.m

Journal Usage Level Changes at Morehouse School of Medicine Library 2011-2020

OBJECTIVE: To determine faculty and researcher journal usage levels and their implications on library’s journal collection and access models for the past five years and compare to previous usage and implications. 1. The librarians would like to investigate changes made in the journal collection as we moved to fewer print based resources through a comparison of usage levels prior to the changes to usage levels after the changes. We had sought to seek optimum pathways for supporting the school’s curricula, research agendas, and health care enterprise. Our ultimate question is ‘How have changes correlated and compared to previous usage and needs of our users?’ 2. METHODS: Using counter statistics (resources such as ScienceDirect, Ovid, Wiley, Nature, and others), ILL records, in-house usage statistics, and interviews, librarians will determine for the past five years (2016-2020) and compare to the previous five years (2011-2015) the: 1. 20 most and 20 least used journals by department and major subject division; 2. 20 most needed, but not owned, journals by department and major subject area; 3. Emerging areas of interest among faculty and researchers; 4. A short survey is to be released to all patrons to determine their preferred resources; 5. Two focus group sessions will be held with faculty and researchers and two with students to solicit additional feedback; 6. Descriptive statistics will be used to show patterns of usage; 7. Comparisons of levels of usage and costs will be made using analyses of variance in mean levels of usage and mean costs; 8. Correlations (Pearson’s r) will be determined between relative costs and usage; 9. Level of MSM related published articles. RESULTS: FY2011-15: 20 journals with the highest numbers of successfully retrieved articles over past 5 years included 2 that were on the list for all 5 years (Journal of Virology and Nature), accounting for 10 of the 20 slots. FY2016-20: All journals in the top 20 used in FY2016 remained for each of the 5 years. FY2011-15 successful use trend was up and down, while for FY2016-20, the trend generally increased until 2020. The sum of the usage of the top 20 journals for each year trended in different ways for 2011-2015 and 2016 and 2020: FY2011-15 successful use trend was up and down, FY2016-20, the trend generally increased until 2020. FY2011-2015 averaged 52,044 successful retrievals per year, while FY2016-2020 averaged 68,549 successful retrievals per year. The sums of the usage of the top 20 journals for 2015 and 2020 totaled 11,776 and 18,908, respectively, representing a 60.51% increase. For FY2019-2020 there were 8 publishers for the 20 most used journals. From FY2010-2011 to FY2019-2020 the fluctuating pattern of faculty publications appear to loosely follow the pattern of journal usage as reflected in the JR1reports. Correlation of publication to use was moderate at .666 and significant at .036. Data shows successful retrievals declined over time for top 20 for FY2011-15, but tended to increase for FY 2016-20 until FY2020. FY2011-2015 averaged 52,044 successful retrievals per year, while FY2016-2020 averaged 68,549 successful retrievals per year. When looking for a relationship between journal cost and usage, only moderate correlations of .406, .638, and .407 were found for FY2016, FY2018, and FY2020, respectively. However, none of the correlations were statistically significant (p = .177, .065, and .133, respectively). CONCLUSIONS: Data shows successful retrievals declined over time for top 20 for FY2011-15, but tended to increase for FY2016-20 until AY2020. FY2011-2015 averaged 52,044 successful retrievals per year, while FY2016-2020 averaged 68,549 successful retrievals per year. When looking for a relationship between journal cost and usage, only moderate correlations of .406, .638, and .407 were found for FY2016, FY2018, and FY2020, respectively. However, none of the correlations were statistically significant (p = .177, .065, and .133, respectively). A significant (p= .036) and devilishly moderate correlation (r=.666) between faculty publication levels and journal use levels was found