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Combining numeric and symbolic learning techniques
Incremental learning from examples in a noisy domain is a difficult problem in Machine Learning. In this paper we divide the task into two subproblems and present a combination of numeric and symbolic approaches that yields robust learning of boolean characterizations. Our method has been implemented in a computer program, and we plot its empirical learning performance in the presence of varying amounts of noise
De novo head and neck cancer after liver transplant with antibody-based immunosuppression induction
Background
Powerful antibody-based immunosuppression induction is now used routinely during organ transplantation, and may place patients at even higher risk of post-transplant cancer.
Materials and Methods
Incidence of de-novo head and neck cancer was extracted from the records of 1685 consecutive adult, deceased donor liver transplant recipients with a minimum 1-year follow-up from 2001 to 2015. There were 121 patients positively identified as having developed de-novo head and neck cancer post-liver transplant. Records of these patients were analyzed to determine demographics, history of cancer pre-liver transplant, de-novo cancer type and location, treatment modalities, and alcohol and tobacco exposure.
Results
Of the 121 patients who developed cancer of the head and neck (7%), there were 103 cutaneous (6%) and 25 non-cutaneous (1%). For non-cutaneous cancers, factors associated with increased risk of cancer included alcohol abuse (p<0.001), any smoking history (p=0.05), and increasing exposure to tobacco (p<0.01). Ten-year Cox regression patient survival demonstrates a survival disadvantage for patients who develop non-cutaneous cancer (p=0.06), but a survival advantage for patients who develop cutaneous cancer (p<0.01).
Conclusions
The incidence and pattern of head and neck cancer in this population of liver transplant patients was similar to those published previously, suggesting that induction immunosuppression does not increase risk of these types of cancers. Long term survival was worse for patients with non-cutaneous cancers, but better for those with cutaneous cancers, though the reason is unclear
Probable Displacement of Riffle-Dwelling Invertebrates by the Introduced Rusty Crayfish, \u3ci\u3eOrconectes Rusticus\u3c/i\u3e (Decapoda: Cambaridae) in a North-Central Wisconsin Stream
The rapid northward range expansion of the rusty crayfish, Orconectes rusticus, and its negative effects on Wisconsin lakes have been the subjects of intense study throughout the last fifteen years. In this study, we investigated the possible impact of rusty crayfish on the benthic macroinvertebrate community structure of the Prairie River in north-central Wisconsin. Rusty crayfish and other invertebrates were collected during August and September, 1994, from three sections of the Prairie River. Rusty crayfish relative abundance increased significantly from the upper to middle, and middle to lower sections; and correlated negatively with a significant 77% decrease in total density of aquatic invertebrates between sections. Mean density of all important invertebrate families and trophic guilds decreased significantly between the upper and lower sections. Due to the similarity of most environmental conditions between river sections, decrease of invertebrates is attributed to the increased abundance of rusty crayfish and its interactions with the native rouna. Our results suggest that a high abundance of rusty crayfish may negatively impact Wisconsin lotic systems
Implementing Options Markets in California To Manage Water Supply Uncertainty
In California, the tremendous spatial and temporal variation in precipitation suggests that flexible contractual arrangements, such as option contracts, would increase allocative efficiency of water over time and space. Under such arrangements, a water agency pays an option premium for the right to purchase water at some point in the future, if water conditions turn out to be dry. The premium represents the value of the flexibility gained by the buyer from postponing its decision whether to purchase water. In California, the seller of existing option arrangements is often an agricultural producer who can fallow land, in the event that a water option is exercised. In this simulation-optimization approach, we seek to determine the value of transferring water uncertainty from one party to another at several locations in California, given current water prices and the spatial and temporal distribution of water year types in the state. (Preliminary analysis covers northern California; future analysis will incorporate southern California.) We analyze within a mathematical programming framework whether increased trading among water agencies across time as well as space would result in significant gains from trade. We use output from CALVIN, an economic-engineering optimization model of the California water system which runs the current configuration of the California water system over historical hydrological conditions, to generate water's imputed price at different locations during different seasons. We also explore reasons why previous theoretical calculations of option value in the western United States have far exceeded option premia on existing bilateral contracts.Risk and Uncertainty,
Lake Michigan Salmonid Stocking Costs in Wisconsin
The costs of stocking salmonids in the Wisconsin waters of Lake Michigan are estimated for 1985. Estimation procedures and costs per stocked and captured fish are presented. Fingerlings of a species were found in most cases to cost more per captured fish than yearlings. However chinook salmon fingerlings were least expensive at an average cost of only 12.67 and $10.14 respectively. While a full policy evaluation awaits additional research on species specific benefits, three tentative conclusions can be drawn for the Wisconsin fishery. First, the role of brook trout in the fishery should be reviewed. Second, despite difficulties with lake trout rehabilitation, the role of lake trout in the sport fishery is encouraging and may justify continued stocking. Finally, increased stocking of the popular chinook salmon may be justified if the recent problems of low capture-per-release rates can be solved.restocking costs, benefit-cost methodology, sport fisheries, salmonids, Lake Michigan, Environmental Economics and Policy, Resource /Energy Economics and Policy,
Automated analysis of quantitative image data using isomorphic functional mixed models, with application to proteomics data
Image data are increasingly encountered and are of growing importance in many
areas of science. Much of these data are quantitative image data, which are
characterized by intensities that represent some measurement of interest in the
scanned images. The data typically consist of multiple images on the same
domain and the goal of the research is to combine the quantitative information
across images to make inference about populations or interventions. In this
paper we present a unified analysis framework for the analysis of quantitative
image data using a Bayesian functional mixed model approach. This framework is
flexible enough to handle complex, irregular images with many local features,
and can model the simultaneous effects of multiple factors on the image
intensities and account for the correlation between images induced by the
design. We introduce a general isomorphic modeling approach to fitting the
functional mixed model, of which the wavelet-based functional mixed model is
one special case. With suitable modeling choices, this approach leads to
efficient calculations and can result in flexible modeling and adaptive
smoothing of the salient features in the data. The proposed method has the
following advantages: it can be run automatically, it produces inferential
plots indicating which regions of the image are associated with each factor, it
simultaneously considers the practical and statistical significance of
findings, and it controls the false discovery rate.Comment: Published in at http://dx.doi.org/10.1214/10-AOAS407 the Annals of
Applied Statistics (http://www.imstat.org/aoas/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Natural Gas Landowner Coalitions in New York State: Emerging Benefits of Collective Natural Resource Management
Thousands of rural landowners in New York State have joined together to form grassroots organizations aimed at collectively bargaining with natural gas companies. The leverage afforded by acting collectively allows these landowner coalitions to potentially influence the economic, environmental, and community impacts of gas development across hundreds of thousands of acres. In-depth interviews with coalition leaders conducted for this article reveal the scope, motivations, and benefits of membership in these groups. Our work examines these elements using multiple frameworks for understanding collective natural resource management. The coalitions are primarily concerned with the advancement of private member benefits, while public benefits of the collective action are poised to accrue indirectly. Group leaders are also contemplating how to use their leverage to secure direct benefits for the wider community – actions that may give communities a modicum of local control over gas development
Prison Research from the Inside: The Role of Convict Autoethnography
A perspective that has often been absent in criminal justice research is that of former prisoners. This article discusses the establishment, in 1997, of “convict criminology,” a group of scholars producing research informed by their experiences of crime and the criminal justice process; that is, either those who have served time themselves or who have operated alongside prisoners as professionals in custodial settings. It is argued that such scholars face similar dilemmas to others in terms of emotionalism, but suggests that their emotions are of a different nature. While an “insider” perspective cannot lay claim to scientific “objectivity,” the article argues that the existence of emotion does not invalidate an “insider” criminologist’s views. Rather, the passion engendered by the experience of incarceration can add color, context, and contour to data collection, findings, and analysis and may therefore be regarded as an essential thread in the tapestry of criminological inquiry
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