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Institution

University of Minnesota

EducationMinneapolis, Minnesota, United States
About: University of Minnesota is a education organization based out in Minneapolis, Minnesota, United States. It is known for research contribution in the topics: Population & Transplantation. The organization has 117432 authors who have published 257986 publications receiving 11944239 citations. The organization is also known as: University of Minnesota, Twin Cities & University of Minnesota-Twin Cities.


Papers
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Journal ArticleDOI
TL;DR: An overview of the methods used in the PROMIS item analyses and proposed calibration of item banks is provided and recommendations are provided for future evaluations of item Banks in HRQOL assessment.
Abstract: Background: The construction and evaluation of item banks to measure unidimensional constructs of health-related quality of life (HRQOL) is a fundamental objective of the Patient-Reported Outcomes Measurement Information System (PROMIS) project. Objectives: Item banks will be used as the foundation for developing short-form instruments and enabling computerized adaptive testing. The PROMIS Steering Committee selected 5 HRQOL domains for initial focus: physical functioning, fatigue, pain, emotional distress, and social role participation. This report provides an overview of the methods used in the PROMIS item analyses and proposed calibration of item banks. Analyses: Analyses include evaluation of data quality (eg, logic and range checking, spread of response distribution within an item), descriptive statistics (eg, frequencies, means), item response theory model assumptions (unidimensionality, local independence, monotonicity), model fit, differential item functioning, and item calibration for banking. Recommendations: Summarized are key analytic issues; recommendations are provided for future evaluations of item banks in HRQOL assessment.

1,251 citations

Journal ArticleDOI
TL;DR: G glycated hemoglobin was similarly associated with a risk of diabetes and more strongly associated with risks of cardiovascular disease and death from any cause as compared with fasting glucose, and measures of risk discrimination showed significant improvement when glycated Hemoglobin was added to models including fasting glucose.
Abstract: Methods We compared the prognostic value of glycated hemoglobin and fasting glucose for identifying adults at risk for diabetes or cardiovascular disease. We measured glycated hemoglobin in whole-blood samples from 11,092 black or white adults who did not have a history of diabetes or cardiovascular disease and who attended the second visit (occurring in the 1990–1992 period) of the Atherosclerosis Risk in Communities (ARIC) study. Results The glycated hemoglobin value at baseline was associated with newly diagnosed diabetes and cardiovascular outcomes. For glycated hemoglobin values of less than 5.0%, 5.0 to less than 5.5%, 5.5 to less than 6.0%, 6.0 to less than 6.5%, and 6.5% or greater, the multivariable-adjusted hazard ratios (with 95% confidence intervals) for diagnosed diabetes were 0.52 (0.40 to 0.69), 1.00 (reference), 1.86 (1.67 to 2.08), 4.48 (3.92 to 5.13), and 16.47 (14.22 to 19.08), respectively. For coronary heart disease, the hazard ratios were 0.96 (0.74 to 1.24), 1.00 (reference), 1.23 (1.07 to 1.41), 1.78 (1.48 to 2.15), and 1.95 (1.53 to 2.48), respectively. The hazard ratios for stroke were similar. In contrast, glycated hemoglobin and death from any cause were found to have a J-shaped association curve. All these associations remained significant after adjustment for the baseline fasting glucose level. The association between the fasting glucose levels and the risk of cardiovascular disease or death from any cause was not significant in models with adjustment for all covariates as well as glycated hemoglobin. For coronary heart disease, measures of risk discrimination showed significant improvement when glycated hemoglobin was added to models including fasting glucose. Conclusions In this community-based population of nondiabetic adults, glycated hemoglobin was similarly associated with a risk of diabetes and more strongly associated with risks of cardiovascular disease and death from any cause as compared with fasting glucose. These data add to the evidence supporting the use of glycated hemoglobin as a diagnostic test for diabetes.

1,249 citations

Journal ArticleDOI
TL;DR: A multidimensional (MD) approach to recommender systems that can provide recommendations based on additional contextual information besides the typical information on users and items used in most of the currentRecommender systems is presented.
Abstract: The article presents a multidimensional (MD) approach to recommender systems that can provide recommendations based on additional contextual information besides the typical information on users and items used in most of the current recommender systems. This approach supports multiple dimensions, profiling information, and hierarchical aggregation of recommendations. The article also presents a multidimensional rating estimation method capable of selecting two-dimensional segments of ratings pertinent to the recommendation context and applying standard collaborative filtering or other traditional two-dimensional rating estimation techniques to these segments. A comparison of the multidimensional and two-dimensional rating estimation approaches is made, and the tradeoffs between the two are studied. Moreover, the article introduces a combined rating estimation method, which identifies the situations where the MD approach outperforms the standard two-dimensional approach and uses the MD approach in those situations and the standard two-dimensional approach elsewhere. Finally, the article presents a pilot empirical study of the combined approach, using a multidimensional movie recommender system that was developed for implementing this approach and testing its performance.

1,248 citations

Book
01 Jan 2000
TL;DR: The Runge-Kutta discontinuous Galerkin (RKDG) method as discussed by the authors is one of the state-of-the-art methods for non-linear convection-dominated problems.
Abstract: In this paper, we review the development of the Runge–Kutta discontinuous Galerkin (RKDG) methods for non-linear convection-dominated problems. These robust and accurate methods have made their way into the main stream of computational fluid dynamics and are quickly finding use in a wide variety of applications. They combine a special class of Runge–Kutta time discretizations, that allows the method to be non-linearly stable regardless of its accuracy, with a finite element space discretization by discontinuous approximations, that incorporates the ideas of numerical fluxes and slope limiters coined during the remarkable development of the high-resolution finite difference and finite volume schemes. The resulting RKDG methods are stable, high-order accurate, and highly parallelizable schemes that can easily handle complicated geometries and boundary conditions. We review the theoretical and algorithmic aspects of these methods and show several applications including nonlinear conservation laws, the compressible and incompressible Navier–Stokes equations, and Hamilton–Jacobi-like equations.

1,246 citations

Journal ArticleDOI
TL;DR: For example, Meehl et al. as discussed by the authors showed that the statistical method is almost always equal to or superior to the clinical method in predicting parole success. But, they also pointed out that even a crude actuarial method such as this was superior to clinical judgment in accuracy.
Abstract: Given a data set about an individual or a group (e.g., interviewer ratings, life history or demographic facts, test results, self-descriptions), there are two modes of data combination for a predictive or diagnostic purpose. The clinical method relies on human judgment that is based on informal contemplation and, sometimes, discussion with others (e.g., case conferences). The mechanical method involves a formal, algorithmic, objective procedure (e.g., equation) to reach the decision. Empirical comparisons of the accuracy of the two methods (136 studies over a wide range of predictands) show that the mechanical method is almost invariably equal to or superior to the clinical method: Common antiactuarial arguments are rebutted, possible causes of widespread resistance to the comparative research are offered, and policy implications of the statistical method's superiority are discussed. In 1928, the Illinois State Board of Parole published a study by sociologist Burgess of the parole outcome for 3,000 criminal offenders, an exhaustive sample of parolees in a period of years preceding. (In Meehl, 1954/1996, this number is erroneously reported as 1,000, a slip probably arising from the fact that 1,000 cases came from each of three Illinois prisons.) Burgess combined 21 objective factors (e.g., nature of crime, nature of sentence, chronological age, number of previous offenses) in unweighted fashion by simply counting for each case the number of factors present that expert opinion considered favorable or unfavorable to successful parole outcome. Given such a large sample, the predetermination of a list of relevant factors (rather than elimination and selection of factors), and the absence of any attempt at optimizing weights, the usual problem of crossvalidation shrinkage is of negligible importance. Subjective, impressionistic, "clinical" judgments were also made by three prison psychiatrists about probable parole success. The psychiatrists were slightly more accurate than the actuarial tally of favorable factors in predicting parole success, but they were markedly inferior in predicting failure. Furthermore, the actuarial tally made predictions for every case, whereas the psychiatrists left a sizable fraction of cases undecided. The conclusion was clear that even a crude actuarial method such as this was superior to clinical judgment in accuracy of prediction. Of course, we do not know how many of the 21 factors the psychiatrists took into account, but all were available to

1,245 citations


Authors

Showing all 118112 results

NameH-indexPapersCitations
Walter C. Willett3342399413322
David J. Hunter2131836207050
David Miller2032573204840
Mark I. McCarthy2001028187898
Dennis W. Dickson1911243148488
David H. Weinberg183700171424
Eric Boerwinkle1831321170971
John C. Morris1831441168413
Aaron R. Folsom1811118134044
H. S. Chen1792401178529
Jie Zhang1784857221720
Jasvinder A. Singh1762382223370
Feng Zhang1721278181865
Gang Chen1673372149819
Hongfang Liu1662356156290
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
2023200
20221,176
202111,903
202011,807
201910,984
201810,367