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Full-Text Articles in Physical Sciences and Mathematics

Generalized Multilevel Functional Regression, Ciprian M. Crainiceanu, Ana-Maria Staicu, Chong-Zhi Di Jan 2009

Generalized Multilevel Functional Regression, Ciprian M. Crainiceanu, Ana-Maria Staicu, Chong-Zhi Di

Chongzhi Di

We introduce Generalized Multilevel Functional Linear Models (GMFLMs), a novel statistical framework for regression models where exposure has a multilevel functional structure. We show that GMFLMs are, in fact, generalized multilevel mixed models. Thus, GMFLMs can be analyzed using the mixed effects inferential machinery and can be generalized within a well-researched statistical framework. We propose and compare two methods for inference: (1) a two-stage frequentist approach; and (2) a joint Bayesian analysis. Our methods are motivated by and applied to the Sleep Heart Health Study, the largest community cohort study of sleep. However, our methods are general and easy to …


Balance Diagnostics For Comparing The Distribution Of Baseline Covariates Between Treatment Groups In Propensity-Score Matched Samples, Peter C. Austin Jan 2009

Balance Diagnostics For Comparing The Distribution Of Baseline Covariates Between Treatment Groups In Propensity-Score Matched Samples, Peter C. Austin

Peter Austin

The propensity score is a subject’s probability of treatment, conditional on observed baseline covariates. Conditional on the true propensity score, treated and untreated subjects have similar distributions of observed baseline covariates. Propensity-score matching is a popular method of using the propensity score in the medical literature. Using this approach, matched sets of treated and untreated subjects with similar values of the propensity score are formed. Inferences about treatment effect made using propensity-score matching are valid only if, in the matched sample, treated and untreated subjects have similar distributions of measured baseline covariates. In this paper we discuss the following methods …


Gone In 60 Seconds: The Absorption Of News In A High-Frequency Betting Market, Babatunde Buraimo, David Peel, Rob Simmons Jan 2008

Gone In 60 Seconds: The Absorption Of News In A High-Frequency Betting Market, Babatunde Buraimo, David Peel, Rob Simmons

Dr Babatunde Buraimo

This paper tests for efficiency in a betting market that offers high-frequency data, the Betfair betting exchange for wagering on outcomes of English Premier League soccer matches. We find clear evidence of rapid adjustment of prices to large disturbances (news). Full adjustment takes place within a one minute interval after the news. This suggests that this particular wagering market is not just efficient at pre-match prices but is also efficient in the face of events within games.


The Black Swan: Praise And Criticism, Peter H. Westfall, Joseph M. Hilbe Aug 2007

The Black Swan: Praise And Criticism, Peter H. Westfall, Joseph M. Hilbe

Joseph M Hilbe

No abstract provided.


A Review Of Limdep 9.0 And Nlogit 4.0, Joseph Hilbe May 2006

A Review Of Limdep 9.0 And Nlogit 4.0, Joseph Hilbe

Joseph M Hilbe

No abstract provided.


Mathematica 5.2: A Review, Joseph Hilbe May 2006

Mathematica 5.2: A Review, Joseph Hilbe

Joseph M Hilbe

No abstract provided.


A Review Of Stata 9.0, Joseph Hilbe Nov 2005

A Review Of Stata 9.0, Joseph Hilbe

Joseph M Hilbe

No abstract provided.


Stochastic Convergence Among European Economies, Mauro Costantini, Claudio Lupi Jan 2005

Stochastic Convergence Among European Economies, Mauro Costantini, Claudio Lupi

Claudio Lupi

The aim of this paper is to test the stochastic convergence in real per capita GDP for 15 European countries using non−stationary panel data approaches over the period 1950−2003. Cross−sectional dependence is assumed due to the existence of strong linkages among European economies. However, tests derived under the assumption of cross−sectional independence are also carried out for completeness and comparison. We also split the whole sample into two sub−periods (1950−1976, 1977−2003) in order to take into account the effects of the first oil crisis (1973−1974) and to evaluate the robustness of the statistical analysis. Our results offer little support to …


Unemployment Scarring In High Unemployment Regions, Claudio Lupi, Patrizia Ordine Jan 2002

Unemployment Scarring In High Unemployment Regions, Claudio Lupi, Patrizia Ordine

Claudio Lupi

This paper investigates the effect of individual unemployment experiences on re-employment wages. The empirical analysis is carried out on a panel of Italian individuals. The main result is that while in the northern regions the effect is similar to the one estimated for the UK, in the southern area of the country the impact is not significant. We link this result to the particular socio-economic environment in which the unemployment spells are experienced. We argue that this might be due to the fact that in a high unemployment environment individual unemployment experiences are perceived as "normal" and do not necessarily …


Testing For Asymmetry In Economic Time Series Using Bootstrap Methods, Claudio Lupi, Patrizia Ordine Jan 2001

Testing For Asymmetry In Economic Time Series Using Bootstrap Methods, Claudio Lupi, Patrizia Ordine

Claudio Lupi

In this paper we show that phase-scrambling bootstrap offers a natural framework for asymmetry testing in economic time series. A comparison with other bootstrap schemes is also sketched. A Monte Carlo analysis is carried out to evaluate the size and power properties of the phase-scrambling bootstrap-based test.


Social Work Assessment Of Adaptive Functioning Using The Vineland Adaptive Behavior Scales: Issues Of Reliability And Validity, Peter Cabrera, Lucienne Grimes-Gaa, Bruce A. Thyer Jan 1999

Social Work Assessment Of Adaptive Functioning Using The Vineland Adaptive Behavior Scales: Issues Of Reliability And Validity, Peter Cabrera, Lucienne Grimes-Gaa, Bruce A. Thyer

Elián P. Cabrera-Nguyen

The assessment of client adaptive functioning is often an important component of a comprehensive social work evaluation. The Vineland Adaptive Behavior Scales (VABS) are the most commonly used quantitative measures of adaptive functioning for clients meeting the criteria for a wide range of disorders. We review the development of the VABS and current knowledge pertaining to the instrument's reliability and validity. We conclude that the ability to administer and interpret the VABS is an important skill for clinical social workers to acquire.


Poicen.Sas : Censored Poisson Regression, Joseph Hilbe, Gordon Johnston Jul 1995

Poicen.Sas : Censored Poisson Regression, Joseph Hilbe, Gordon Johnston

Joseph M Hilbe

SAS Macro to estimate censored Poisson data, using method of Hilbe. See Hilbe, Joseph M (2011), Negative Binomial Regression, 2nd ed (Cambridge University Press)


Generalized Linear Models: Software Implementation And The Structure Of A General Power-Link Based Glm Algorithm, Joseph Hilbe Apr 1993

Generalized Linear Models: Software Implementation And The Structure Of A General Power-Link Based Glm Algorithm, Joseph Hilbe

Joseph M Hilbe

Generalized linear modeling (GLM) is currently undergoing a renaissance. The number of software packages offering GLM capability grows each year and as a partial consequence one finds an increased number of research endeavors being modeled using GLM methodology. On the other hand, there have likewise been an increasing number of requests to vendors by users of statistical packages to include GLM facilities amid other offerings. The overall effect has been a near 300 percent increase in GLM programs over the past four years.

I shall discuss the nature of generalized linear models followed by an examination of how they have …


Direct Tests Of The Rational Expectations Hypothesis: A Study Of Italian Entrepreneurs’ Inflationary Expectations (1980-1988), Claudio Lupi Jan 1989

Direct Tests Of The Rational Expectations Hypothesis: A Study Of Italian Entrepreneurs’ Inflationary Expectations (1980-1988), Claudio Lupi

Claudio Lupi

The primary concern of this paper is to test the rational expectations hypothesis for Italian entrepreneurs' inflationary expectations between 1980 and 1988 using monthly observed expectations. Particular care is devoted to analyzing the problems arising when multiperiod expectations and a nonwhite noise measurement error in the expectations series are considered. The empirical analysis is carried out using cross correlations on ARIMA residuals and transfer function models. This technique seems to be particularly appealing for rationality testing.


The Pseudo-Problem Of Induction, Joseph Hilbe Sep 1971

The Pseudo-Problem Of Induction, Joseph Hilbe

Joseph M Hilbe

Paper I delivered at the IVth International Congress for Logic, Methodology, and Philosophy of Science held in Bucharest, Romania in 1971.