Statistical Methods for Optimally Locating Automatic Traffic Recorders

This report presents new computer-based statistical methods for the optimal placement of automatic traffic recorders (ATR). The goal of each method is to locate a set of ATRs so as to improve the overall efficiency and accuracy of Annual Average Daily Traffic (AADT) estimates. The precise estimation of AADTs is essential because of the important role they play in many highway design, maintenance, and safety decisions. Because of the huge number of potential ATR sites in a typical state highway, optimal selection of ATR sites is a very large combinatorial problem. Accordingly, site selection is currently accomplished through judgmental and/or design-based sampling techniques (e.g., random sampling). By developing fast and efficient computer algorithms to accomplish the purposive selection of an optimal sample, we demonstrate that model-based sampling is a viable alternative to classical design-based sampling techniques. The algorithms developed in this project include an exchange algorithm and a two-stage sampling algorithm. In the rank-1 exchange algorithm, ATR sites are sequentially added to and deleted from the design. It generates highly efficient designs without exhaustively searching through all possible designs. In the two-stage sampling approach, similar sites are statistically clustered, then approximate design techniques are used to calculate the optimal weight for each cluster. Based on these optimal weights, a random sample of sites is selected from within each cluster. The speed of this two-stage sampling algorithm makes it an ideal approach for large-scale problems. Using traffic data provided by the Minnesota Department of Transportation, we demonstrate empirically that both algorithms are substantially better in terms of average variance of prediction than simple random sampling.University of Minnesota Center for Transportation Studies, U.S. Department of Transportation, and the Mountain-Plains Consortiu

Recent Studies in Andean Prehistory and Protohistory: Papers from the Second Annual Northeast Conference on Andean Archaeology and Ethnohistory

The contributions in this volume represent nine of the twenty-three papers presented at the Second Annual Northeast Conference on Andean Archaeology and Ethnohistory (NCAAE) held at the American Museum of Natural History on November 19-20, 1983. Papers include The Preceramic and Formative Period Occupations in the Cordillera Negra: Preliminary Report by Michael A. Malpass, The Early Horizon--Early Intermediate Period Transition: A View from the Nepena and Viru Valleys by Richard E. Daggett, Paracas in Chincha and Pisco: A Reappraisal of the Ocucaje Sequence by Dwight T. Wallace, Impressions in Metal: Reconstructing Burial Context at Loma Negra, Peru by Anne-Louise Schaeffer, The Moche Moon by Elizabeth P. Benson, Archaeological Investigation in the Andean Piedmont and High Llanos of Western Venezuela: A Preliminary Report by Charles S. Spencer and Elsa M. Redmond, Pachacamac--An Andean Oracle Under Inca Rule by Thomas C. Patterson, The Spanish League and Inca Sites: A Reassessment of the Itinerary of Juan de Matienzo through N.W. Argentina by Gordon C. Pollard, and Written Sources on Andean Cosmogony by George Kubler.https://digitalcommons.library.umaine.edu/andean_past_special/1001/thumbnail.jp

Low serum magnesium and 1-year mortality in alcohol withdrawal syndrome

Background: In 2014, the WHO reported that 6% of all deaths were attributable to excess alcohol consumption. The aim of the present study was to examine the relationship between serum magnesium concentrations and mortality in patients with alcohol withdrawal syndrome (AWS). Materials and methods: A retrospective review of 700 patients with documented evidence of previous AWS indicating a requirement for benzodiazepine prophylaxis or evidence of alcohol withdrawal syndrome between November 2014 and March 2015. Results: Of 380 patients included in the sample analysis, 64 (17%) were dead at 1 year following the time of treatment for AWS. The majority of patients had been prescribed thiamine (77%) and a proton pump inhibitor (66%). In contrast, the majority of patients had low circulating magnesium concentrations (2 (P  50 years (OR 3.37, 95% CI 1.52-7.48, P 2 (OR 3.10, 95% CI 1.38-6.94, P < 0.01) and magnesium < 0.75 mmol/L (OR 4.11, 95% CI 1.3-12.8, P < 0.05) remained independently associated with death at 1 year. Conclusion: Overall, 1-year mortality was significantly higher among those patients who were magnesium deficient (<0.75 mmol/L) when compared to those who were replete (≥0.75 mmol/L; P < 0.001)

Consistency of cosmic microwave background temperature measurements in three frequency bands in the 2500-square-degree SPT-SZ survey

We present an internal consistency test of South Pole Telescope (SPT) measurements of the cosmic microwave background (CMB) temperature anisotropy using three-band data from the SPT-SZ survey. These measurements are made from observations of ~2500 deg^2 of sky in three frequency bands centered at 95, 150, and 220 GHz. We combine the information from these three bands into six semi-independent estimates of the CMB power spectrum (three single-frequency power spectra and three cross-frequency spectra) over the multipole range 650 < l < 3000. We subtract an estimate of foreground power from each power spectrum and evaluate the consistency among the resulting CMB-only spectra. We determine that the six foreground-cleaned power spectra are consistent with the null hypothesis, in which the six cleaned spectra contain only CMB power and noise. A fit of the data to this model results in a chi-squared value of 236.3 for 235 degrees of freedom, and the probability to exceed this chi-squared value is 46%.Comment: 21 pages, 4 figures, current version matches version published in JCA

Sustainability appraisal: Jack of all trades, master of none?

Sustainable development is a commonly quoted goal for decision making and supports a large number of other discourses. Sustainability appraisal has a stated goal of supporting decision making for sustainable development. We suggest that the inherent flexibility of sustainability appraisal facilitates outcomes that often do not adhere to the three goals enshrined in most definitions of sustainable development: economic growth, environmental protection and enhancement, and the wellbeing of the human population. Current practice is for sustainable development to be disenfranchised through the interpretation of sustainability, whereby the best alternative is good enough even when unsustainable. Practitioners must carefully and transparently review the frameworks applied during sustainability appraisal to ensure that outcomes will meet the three goals, rather than focusing on a discourse that emphasises one or more goals at the expense of the other(s)

New constraints on the evolution of the stellar-to-dark matter connection : a combined analysis of galaxy-galaxy lensing, clustering, and stellar mass functions from z = 0.2 to z = 1

Using data from the COSMOS survey, we perform the first joint analysis of galaxy-galaxy weak lensing, galaxy spatial clustering, and galaxy number densities. Carefully accounting for sample variance and for scatter between stellar and halo mass, we model all three observables simultaneously using a novel and self-consistent theoretical framework. Our results provide strong constraints on the shape and redshift evolution of the stellar-to-halo mass relation (SHMR) from z = 0.2 to z = 1. At low stellar mass, we find that halo mass scales as Mh vpropM 0.46 * and that this scaling does not evolve significantly with redshift from z = 0.2 to z = 1. The slope of the SHMR rises sharply at M * > 5 × 1010 M ☉ and as a consequence, the stellar mass of a central galaxy becomes a poor tracer of its parent halo mass. We show that the dark-to-stellar ratio, Mh /M *, varies from low to high masses, reaching a minimum of Mh /M * ~ 27 at M * = 4.5 × 1010 M ☉ and Mh = 1.2 × 1012 M ☉. This minimum is important for models of galaxy formation because it marks the mass at which the accumulated stellar growth of the central galaxy has been the most efficient. We describe the SHMR at this minimum in terms of the "pivot stellar mass," M piv *, the "pivot halo mass," M piv h , and the "pivot ratio," (Mh /M *)piv. Thanks to a homogeneous analysis of a single data set spanning a large redshift range, we report the first detection of mass downsizing trends for both M piv h and M piv *. The pivot stellar mass decreases from M piv * = 5.75 ± 0.13 × 1010 M ☉ at z = 0.88 to M piv * = 3.55 ± 0.17 × 1010 M ☉ at z = 0.37. Intriguingly, however, the corresponding evolution of M piv h leaves the pivot ratio constant with redshift at (Mh /M *)piv ~ 27. We use simple arguments to show how this result raises the possibility that star formation quenching may ultimately depend on Mh /M * and not simply on Mh , as is commonly assumed. We show that simple models with such a dependence naturally lead to downsizing in the sites of star formation. Finally, we discuss the implications of our results in the context of popular quenching models, including disk instabilities and active galactic nucleus feedback

A Comparison of Maps and Power Spectra Determined from South Pole Telescope and Planck Data

We study the consistency of 150 GHz data from the South Pole Telescope (SPT) and 143 GHz data from the Planck satellite over the patch of sky covered by the SPT-SZ survey. We first visually compare the maps and find that the residuals appear consistent with noise after accounting for differences in angular resolution and filtering. We then calculate (1) the cross-spectrum between two independent halves of SPT data, (2) the cross-spectrum between two independent halves of Planck data, and (3) the cross-spectrum between SPT and Planck data. We find the three cross-spectra are well-fit (PTE = 0.30) by the null hypothesis in which both experiments have measured the same sky map up to a single free calibration parameter---i.e., we find no evidence for systematic errors in either data set. As a by-product, we improve the precision of the SPT calibration by nearly an order of magnitude, from 2.6% to 0.3% in power. Finally, we compare all three cross-spectra to the full-sky Planck power spectrum and find marginal evidence for differences between the power spectra from the SPT-SZ footprint and the full sky. We model these differences as a power law in spherical harmonic multipole number. The best-fit value of this tilt is consistent among the three cross-spectra in the SPT-SZ footprint, implying that the source of this tilt is a sample variance fluctuation in the SPT-SZ region relative to the full sky. The consistency of cosmological parameters derived from these datasets is discussed in a companion paper.Comment: 15 pages, 9 figures. Published in The Astrophysical Journal. Current arxiv version matches published versio

Sunyaev-Zel'dovich Cluster Profiles Measured with the South Pole Telescope

We present Sunyaev-Zel'dovich measurements of 15 massive X-ray selected galaxy clusters obtained with the South Pole Telescope. The Sunyaev-Zel'dovich (SZ) cluster signals are measured at 150 GHz, and concurrent 220 GHz data are used to reduce astrophysical contamination. Radial profiles are computed using a technique that takes into account the effects of the beams and filtering. In several clusters, significant SZ decrements are detected out to a substantial fraction of the virial radius. The profiles are fit to the beta model and to a generalized NFW pressure profile, and are scaled and stacked to probe their average behavior. We find model parameters that are consistent with previous studies: beta=0.86 and r_core/r_500 = 0.20 for the beta model, and (alpha, beta, gamma, c_500)=(1.0,5.5,0.5,1.0) for the generalized NFW model. Both models fit the SPT data comparably well, and both are consistent with the average SZ profile out to the virial radius. The integrated Compton-y parameter Y_SZ is computed for each cluster using both model-dependent and model-independent techniques, and the results are compared to X-ray estimates of cluster parameters. We find that Y_SZ scales with Y_X and gas mass with low scatter. Since these observables have been found to scale with total mass, our results point to a tight mass-observable relation for the SPT cluster survey.Comment: 21 pages, 24 figures, updated to published versio

A Comparison of Cosmological Parameters Determined from CMB Temperature Power Spectra from the South Pole Telescope and the Planck Satellite

The Planck cosmic microwave background (CMB) temperature data are best fit with a LCDM model that is in mild tension with constraints from other cosmological probes. The South Pole Telescope (SPT) 2540 $\text{deg}^2$ SPT-SZ survey offers measurements on sub-degree angular scales (multipoles $650 \leq \ell \leq 2500$) with sufficient precision to use as an independent check of the Planck data. Here we build on the recent joint analysis of the SPT-SZ and Planck data in \citet{hou17} by comparing LCDM parameter estimates using the temperature power spectrum from both data sets in the SPT-SZ survey region. We also restrict the multipole range used in parameter fitting to focus on modes measured well by both SPT and Planck, thereby greatly reducing sample variance as a driver of parameter differences and creating a stringent test for systematic errors. We find no evidence of systematic errors from such tests. When we expand the maximum multipole of SPT data used, we see low-significance shifts in the angular scale of the sound horizon and the physical baryon and cold dark matter densities, with a resulting trend to higher Hubble constant. When we compare SPT and Planck data on the SPT-SZ sky patch to Planck full-sky data but keep the multipole range restricted, we find differences in the parameters $n_s$ and $A_se^{-2\tau}$. We perform further checks, investigating instrumental effects and modeling assumptions, and we find no evidence that the effects investigated are responsible for any of the parameter shifts. Taken together, these tests reveal no evidence for systematic errors in SPT or Planck data in the overlapping sky coverage and multipole range and, at most, weak evidence for a breakdown of LCDM or systematic errors influencing either the Planck data outside the SPT-SZ survey area or the SPT data at $\ell >2000$.Comment: 14 pages, 7 figures. Updated 1 figure and expanded on the reasoning for fixing the affect of lensing on the power spectrum instead of varying Alen