Miracle-dz/UniFAR-FTUs huggingface dataset:
Can Free Entry Be Inefficient? Fixed Commissions and Social Waste in the Real Estate Industry

Real estate agents typically charge a 6 percent commission, regardless of the price of the house sold. As a consequence, the commission fee from selling a house will differ dramatically across cities depending on the average price of housing, although the effort necessary to match buyers and sellers may not be that different. We use a simple economic model to show that if barriers to entry are low, the entry of real estate agents in cities with high housing prices is socially inefficient. Consistent with our model, we find that when the average price of land in a city increases, (1) the fraction of real estate brokers in a city increases, (2) the productivity of an average real estate agent (houses sold per hour worked) falls, and (3) the real wage of a typical real estate agent remains unchanged. We cannot completely rule out the alternative explanation that these results reflect unmeasured differences in the quality of broker services. However, we present evidence that as the average price of housing in a city increases, there is only a small increase in the amount of time a buyer spends searching for a house, and the average time a house for sale stays on the market falls.
Do Prediction Markets Produce Well�?Calibrated Probability Forecasts?

This article presents new theoretical and empirical evidence on the forecasting ability of prediction markets. We develop a model that predicts that the time until expiration of a prediction market should negatively affect the accuracy of prices as a forecasting tool in the direction of a ‘favourite/longshot bias’. That is, high-likelihood events are underpriced, and low-likelihood events are over-priced. We confirm this result using a large data set of prediction market transaction prices. Prediction markets are reasonably well calibrated when time to expiration is relatively short, but prices are significantly biased for events farther in the future. When time value of money is considered, the miscalibration can be exploited to earn excess returns only when the trader has a relatively low discount rate.
Driver mutations in TP53 are ubiquitous in high grade serous carcinoma of the ovary

Numerous studies have tested the association between TP53 mutations in ovarian cancer and prognosis but these have been consistently confounded by limitations in study design, methodology, and/or heterogeneity in the sample cohort. High‐grade serous (HGS) carcinoma is the most clinically important histological subtype of ovarian cancer. As these tumours may arise from the ovary, Fallopian tube or peritoneum, they are collectively referred to as high‐grade pelvic serous carcinoma (HGPSC). To identify the true prevalence of TP53 mutations in HGPSC, we sequenced exons 2–11 and intron–exon boundaries in tumour DNA from 145 patients. HGPSC cases were defined as having histological grade 2 or 3 and FIGO stage III or IV. Surprisingly, pathogenic TP53 mutations were identified in 96.7% (n = 119/123) of HGPSC cases. Molecular and pathological review of mutation‐negative cases showed evidence of p53 dysfunction associated with copy number gain of MDM2 or MDM4, or indicated the exclusion of samples as being low‐grade serous tumours or carcinoma of uncertain primary site. Overall, p53 dysfunction rate approached 100% of confirmed HGPSCs. No association between TP53 mutation and progression‐free or overall survival was found. From this first comprehensive mapping of TP53 mutation rate in a homogeneous group of HGPSC patients, we conclude that mutant TP53 is a driver mutation in the pathogenesis of HGPSC cancers. Because TP53 mutation is almost invariably present in HGPSC, it is not of substantial prognostic or predictive significance. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Bandit Problems with Lévy Processes

Bandit problems model the trade-off between exploration and exploitation in various decision problems. We study two-armed bandit problems in continuous time, where the risky arm can have two types: High or Low; both types yield stochastic payoffs generated by a Levy process. We show that the optimal strategy is a cut-off strategy and we provide an explicit expression for the cut-off and for the optimal payoff.
ON THE ESTIMATION OF DEMAND SYSTEMS WITH LARGE NUMBER OF GOODS: AN APPLICATION TO SOUTH AFRICA HOUSEHOLD FOOD DEMAND

The estimation of large demand systems to investigate the patterns of consumption of households is notoriously difficult. This study develops a modified Almost Ideal Demand System model based on a flexible two-stage budgeting demand modelling framework to examine the effect of estimation procedures (Bottom-up and Top-down) on South African household food consumption parameters. Household food consumption was divided into seven broad food groups: meat and fish; grains; dairy products; fruits; vegetables; other foods. The demand systems were estimated using data from the 1993 South Africa Integrated Household Survey (SIHS) conducted by the South African Labour and Development Research Unit (SALDRU). Empirical results indicate that the Top-down approach is more suited for estimation of South African household food demand. Results indicate that own-price do play an important role in influencing household food consumption. Results also indicate no presence of gross substitution between and within food groups. Expenditure elasticity estimates indicate that meat and fish, dairy products and fruits are luxury products, while grains, vegetables and other foods are necessities in South African household diet.
Working abroad, working with others: How firms learn to operate international joint ventures

Successful international joint ventures entail both learning to operate across national boundaries and learning to cooperate. Hypotheses grounded in organizational learning theory were tested with event-history analysis and data on 1,493 expansions of 25 large Dutch firms between 1966 and 1994. Experience with domestic joint ventures and with international wholly owned subsidiaries contributed to the longevity of international joint ventures, but prior experience with international joint ventures did not.
Multistage speaker diarization of broadcast news

This paper describes recent advances in speaker diarization with a multistage segmentation and clustering system, which incorporates a speaker identification step. This system builds upon the baseline audio partitioner used in the LIMSI broadcast news transcription system. The baseline partitioner provides a high cluster purity, but has a tendency to split data from speakers with a large quantity of data into several segment clusters. Several improvements to the baseline system have been made. First, the iterative Gaussian mixture model (GMM) clustering has been replaced by a Bayesian information criterion (BIC) agglomerative clustering. Second, an additional clustering stage has been added, using a GMM-based speaker identification method. Finally, a post-processing stage refines the segment boundaries using the output of a transcription system. On the National Institute of Standards and Technology (NIST) RT-04F and ESTER evaluation data, the multistage system reduces the speaker error by over 70% relative to the baseline system, and gives between 40% and 50% reduction relative to a single-stage BIC clustering system
The variable colours of the fiddler crab Uca vomeris and their relation to background and predation

SUMMARY Colour changes in fiddler crabs have long been noted, but a functional interpretation is still lacking. Here we report that neighbouring populations of Uca vomeris in Australia exhibit different degrees of carapace colours, which range from dull mottled to brilliant blue and white. We determined the spectral characteristics of the mud substratum and of the carapace colours of U. vomeris and found that the mottled colours of crabs are cryptic against this background, while display colours provide strong colour contrast for both birds and crabs, but luminance contrast only for a crab visual system. We tested whether crab populations may become cryptic under the influence of bird predation by counting birds overflying or feeding on differently coloured colonies. Colonies with cryptically coloured crabs indeed experience a much higher level of bird presence, compared to colourful colonies. We show in addition that colourful crab individuals subjected to dummy bird predation do change their body colouration over a matter of days. The crabs thus appear to modify their social signalling system depending on their assessment of predation risk.
An endpoint estimate for the Kunze-Stein phenomenon and related maximal operators

One of the purposes of this paper is to prove that if G is a noncompact connected semisimple Lie group of real rank one with flnite center, then L 2;1 (G)⁄L 2;1 (G)µ L 2;1 (G): Let K be a maximal compact subgroup of G and X = G=K a symmetric space of real rank one. We will also prove that the noncentered maximal operator M2f(z) = sup2B 1 jBj Z B jf(z 0 )jdz 0 is bounded from L 2;1 (X )t oL 2;1 (X) and from L p (X )t oL p (X) in the sharp range of exponents p2 (2;1]. The supremum in the deflnition ofM2f(z )i s taken over all balls containing the point z.
Trading Institutions in Experimental Asset Markets: Theory and Evidence

We report the results of an experiment designed to study the role of institutional structure in the formation of bubbles and crashes in laboratory asset markets. In this study, in addition to Call Market and Double Auction, we employ the Tâtonnement trading institution, which has not been previously explored in laboratory asset markets, despite its historical and contemporary relevance. The results show that bubbles are significantly smaller in Tâtonnement than in Double Auction, suggesting that the trading institution plays a crucial role in the formation of bubbles. We provide a heterogeneous agent model with speculators, fundamental and noise traders to better understand these results. For each trading institution, we provide structural estimates of the parameters of the model using experimental data. The model allows us to identify the different types of traders empirically. We find that speculation is more prominent in Double Auction than in other trading institutions. Furthermore, Tâtonnement produces more accurate and less dispersed (among traders) price forecasts towards the end of the experiment, which indicates that Tâtonnement favors more homogenous expectations.
Transfer pricing under asymmetric information

This paper analyses optimal transfer prices in a firm organized in two divisions. The production costs of the divisions are their respective private information. The objective of headquarters is to determine the transfer pricing method that maximizes total profit less managers' compensation. Managers are interested in their current compensation and in the market evaluation of their experience. In this setting, the paper discusses why particular transfer pricing methods found in practice and literature may induce-inefficiencies, and it identifies conditions under which each method is preferable. Major results are: a market-based transfer price does not implement the first-best solution if there are benefits from internal trade; cost-based transfer,prices may achieve first-best, and they are preferable to negotiated transfer prices if communication is cost-less; dual transfer prices do not implement the first-best solution, as long as collusion cannot be discouraged. 'There are two truisms in business. Transfer prices are wrong and charges for corporate overhead are too high. '1
Altered Renal Sodium Transporter Expression in an Animal Model of Type 2 Diabetes Mellitus

Hemodynamic factors play an important role in the development and/or progression of diabetic nephropathy. We hypothesized that renal sodium transporter dysregulation might contribute to the hemodynamic alterations in diabetic nephropathy. Otsuka Long Evans Tokushima Fatty (OLETF) rats were used as an animal model for type 2 diabetes. Long Evans Tokushima (LETO) rats were used as controls. Renal sodium transporter regulation was investigated by semiquantitative immunoblotting and immunohistochemistry of the kidneys of 40-week-old animals. The mean serum glucose level in OLETF rats was increased to 235±25 mg/dL at 25 weeks, and the hyperglycemia continued up to the end of 40 weeks. Urine protein/creatinine ratios were 10 times higher in OLETF rats than in LETO rats. At 40th week, the abundance of the epithelial sodium channel (ENaC) β-subunit was increased in OLETF rats, but the abundance of the ENaC γ-subunit was decreased. No significant differences were observed in the ENaC α-subunit or other major sodium transporters. Immunohistochemistry for the ENaC β-subunit showed increased immunoreactivity in OLETF rats, whereas the ENaC γ-subunit showed reduced immunoreactivity in these rats. In OLETF rats, ENaC β-subunit upregulation and ENaC γ-subunit downregulation after the development of diabetic nephropathy may reflect an abnormal sodium balance.
On Optimal Algorithms for List Ranking in the Parallel External Memory Model with Applications to Treewidth and other Elementary Graph Problems

The performance of many algorithms on large input instances substantially depends on the number of triggered cache misses instead of the number of executed operations. This behavior is captured by the external memory model in a natural way. It models a computer by a fast cache of bounded size and a conceptually infinite (external) memory. In contrast to the classical RAMmodel, the complexity measure is the number of cache lines transferred between the cache and the memory. Computations on elements in the cache are not counted. Recent trends in processor design and advances in big data computing require massively parallel algorithms. The parallel external memory (PEM) model extends the external memory model so that it also captures parallelism. It consists of multiple processors which each have a private cache and share the (external) memory. This thesis considers three computational problems in the context of (parallel) external memory algorithms. For the fundamental problem of list ranking, previously, an algorithm was known that has sorting complexity for many settings of the PEM model. In the first part of this thesis, this algorithm is complemented by matching lower bounds for most practical settings. Interestingly, a stronger lower bound for parameter ranges which previously have not been considered is shown. By modeling how list ranking algorithms retrieve information on the structure of the list in the memory, we give a lower bound that is quadratic in sorting complexity for certain parameter settings. It is noteworthy that this result implies the first non-trivial lower bounds for list ranking for the bulk synchronous parallel and the MapReduce model. These lower bounds are complemented by a list ranking algorithm which is, in contrast to previous algorithms, analyzed for all parameter settings of the PEM model. In the second part, an efficient algorithm for the PEM model to compute a tree decomposition of bounded width for a graph is presented. The main challenge is to implement a load balancing strategy such that the running
Does Purchasing Power Parity Work?

The logarithm of the purchasing power ratio (PPR) is shown for seven countries and three alternative price indices to follow a stationary and invertible process in the first differences. This means that permanent shifts in the parity value accumulate over time. Therefore, as the prediction interval lengthens, the variance of the level of the PPR goes towards infinity while the variance of its average growth rate goes to zero. Since the variance of the permanent shifts is substantial: (1) Harmonized money growth cannot maintain constant exchange rates; reserve flows feedback is required. (2) Economic explanations of the permanent shifts are an important research topic.
Population Genetic Analysis Infers Migration Pathways of Phytophthora ramorum in US Nurseries

Recently introduced, exotic plant pathogens may exhibit low genetic diversity and be limited to clonal reproduction. However, rapidly mutating molecular markers such as microsatellites can reveal genetic variation within these populations and be used to model putative migration patterns. Phytophthora ramorum is the exotic pathogen, discovered in the late 1990s, that is responsible for sudden oak death in California forests and ramorum blight of common ornamentals. The nursery trade has moved this pathogen from source populations on the West Coast to locations across the United States, thus risking introduction to other native forests. We examined the genetic diversity of P. ramorum in United States nurseries by microsatellite genotyping 279 isolates collected from 19 states between 2004 and 2007. Of the three known P. ramorum clonal lineages, the most common and genetically diverse lineage in the sample was NA1. Two eastward migration pathways were revealed in the clustering of NA1 isolates into two groups, one containing isolates from Connecticut, Oregon, and Washington and the other isolates from California and the remaining states. This finding is consistent with trace forward analyses conducted by the US Department of Agriculture's Animal and Plant Health Inspection Service. At the same time, genetic diversities in several states equaled those observed in California, Oregon, and Washington and two-thirds of multilocus genotypes exhibited limited geographic distributions, indicating that mutation was common during or subsequent to migration. Together, these data suggest that migration, rapid mutation, and genetic drift all play a role in structuring the genetic diversity of P. ramorum in US nurseries. This work demonstrates that fast-evolving genetic markers can be used to examine the evolutionary processes acting on recently introduced pathogens and to infer their putative migration patterns, thus showing promise for the application of forensics to plant pathogens.
Accelerating External Sorting via On-the-fly Data Merge in Active SSDs

The concept of active SSDs (solid state drives) has been introduced in order to cope with the demands required to process the ever-increasing volumes of data. In active SSDs, some of the data-processing tasks are offloaded to SSDs, freeing host system resources and improving overall performance of data analysis. In this paper, we propose a novel active SSD architecture focused on improving the external sorting algorithm that is used extensively in data-intensive computing. By performing merge operations on-the-fly in active SSDs, our method can remove the extra data transfer and enhance the lifetime of SSDs. Our evaluation results on a real SSD platform indicate that the proposed scheme out-performs the traditional external sorting by up to 39%.
A Remarkable Elevation of Freezing Temperature of CCl4 in Graphitic Micropores

The freezing behavior of CCl 4 confined in graphitic micropores of activated carbon fibers (ACFs) was examined by use of differential scanning calorimetry over the temperature range of 180 to 320 K. For ACF of average pore width,w ) 1.1 nm, we observed a clear peak showing that the freezing temperature is 299 K. The freezing temperature was elevated by 57 K. However, the enthalpy of freezing was only 1.0% of that of the bulk liquid CCl4 to an fcc solid phase. CCl 4 confined in micropores of w ) 0.80 nm had a more diffuse DSC peak, providing a similar elevation of the freezing temperature and an even smaller freezing enthalpy of 0.5% of the bulk value.
University of Birmingham Towards a System Level Understanding of Non-Model Organisms Sampled from the Environment: A Network Biology Approach

The acquisition and analysis of datasets including multi-level omics and physiology from non-model species, sampled from field populations, is a formidable challenge, which so far has prevented the application of systems biology approaches. If successful, these could contribute enormously to improving our understanding of how populations of living organisms adapt to environmental stressors relating to, for example, pollution and climate. Here we describe the first application of a network inference approach integrating transcriptional, metabolic and phenotypic information representative of wild populations of the European flounder fish, sampled at seven estuarine locations in northern Europe with different degrees and profiles of chemical contaminants. We identified network modules, whose activity was predictive of environmental exposure and represented a link between molecular and morphometric indices. These sub-networks represented both known and candidate novel adverse outcome pathways representative of several aspects of human liver pathophysiology such as liver hyperplasia, fibrosis, and hepatocellular carcinoma. At the molecular level these pathways were linked to TNF alpha, TGF beta, PDGF, AGT and VEGF signalling. More generally, this pioneering study has important implications as it can be applied to model molecular mechanisms of compensatory adaptation to a wide range of scenarios in wild populations.
Type II Quasars from the Sloan Digital Sky Survey. IV. Chandra and XMM-Newton Observations Reveal Heavily Absorbed Sources

We are carrying out sensitive X-ray observations with Chandra and XMM-Newton of type II quasars selected from the Sloan Digital Sky Survey based on their optical emission line properties. In this paper we present the first results of our program. We present observations of four objects at redshifts 0.4 < z < 0.8, and an analysis of the archival data for four additional objects in the same redshift range. Six of the eight were detected in X-rays; five of them have sufficient signal to derive spectral information. All of the detected sources have intrinsic luminosities L2-10 keV > 5 × 1043ergs s-1; the five with sufficient counts for spectral fitting show evidence for significant absorption (NH ≳ a few×1022 cm-2). At least three of the objects likely have NH > 1023 cm-2; some may be Compton-thick (NH > 1024 cm-2). In the five objects for which we could fit spectra, the slopes tend to be significantly flatter than typically observed in AGNs; it is possible that this is due either to reprocessing of the nuclear emission or to a line of sight that passes through patchy absorption.
What constitutes a high quality discharge summary? A comparison between the views of secondary and primary care doctors

Objective This study aimed to identify any differences in opinion between UK hospital junior doctors and community General Practitioners (GPs) with respect to the ideal content and characteristics of discharge summaries, and to explore junior doctors’ training for and awareness of post-discharge requirements of GPs. Methods A piloted anonymous survey was posted to 74 junior doctors at a UK general hospital and 153 local GPs. Doctors were asked to rank discharge summary key content and characteristics in order of importance. GP discharge summary preferences and junior doctor training were also investigated. Non-respondents, identified by non-receipt of a separate participation card, were followed up once. Results Thirty-six (49%) junior doctors and 42 (28%) GPs returned completed questionnaires. Accuracy was a priority with 24 (72%) GPs and 28 (88%) junior doctors ranking it most important. Details of medication changes were considered most important by 13 (39%) GPs and 4 (12%) junior doctors. Inadequate training in discharge summary writing was reported by 13 (36%) junior doctors. Conclusions Although based on small sample sizes from one location, the level and range of differences in perceived importance of reporting medication changes suggests that many discharge summaries may not currently fulfil GP requirements for managing continuity of care. Results indicate that over a third of junior doctors felt inadequately prepared for writing discharge summaries. There may therefore be both a need and professional support for further training in discharge summary writing, requiring confirmatory research.