PROPENSITY SCORE MATCHING FOR SURGICAL OUTCOMES WITH OBSERVATIONAL DATA Robert M. Cannon, 3/26/2012 Because of limitations in randomized controlled trials, medical researchers are often forced to rely upon studies of observational data. Confounding is a major difficulty encountered in such studies that can create considerable bias in estimates of treatment effects. Propensity score analysis was...

The purpose of this study is to develop portfolio optimization and assets allocation using our proposed models. The study is based on a non-parametric efficiency analysis tool, namely Data Envelopment Analysis (DEA). Conventional DEA models assume non-negative data for inputs and outputs. However, many of these data take the negative value, therefore we propose the MeanSharp-βRisk (MShβR) model...

background: several studies have demonstrated an increased risk of congenital hypothyroidism (ch) in girls in comparison to boys. objectives: the aim of this study was to determine the potential interactions that are able to change the effect of gender on congenital hypothyroidism. patients and methods: we conducted a matched 1:4 case-control study in hamadan province, western of iran, from 200...

Represented Coxeter matroids of types Cn and Dn, that is, symplectic and orthogonal matroids arising from totally isotropic subspaces of symplectic or (even-dimensional) orthogonal spaces, may also be represented in buildings of type Cn and Dn, respectively (see [4, Chapter 7]). Indeed, the particular buildings involved are those arising from the flags or oriflammes, respectively, of totally is...

Robert C. Turner Skidmore College Abstract After the 2000 presidential election, twenty-one states considered legislation to award their presidential electors using the district system, wherein one elector is awarded to the popular vote winner of each congressional district and the two state electors are awarded to the popular vote winner statewide. Historically, the district system is viewed a...

The influence of market sentiments on the bankruptcy risk propensity firms has been extensively explored in literature. However, less attention paid to whether corporate life cycle plays any role this nexus. purpose research is unveil how responds sentiments, and sentiments–risk relationship varies over different stages cycle. Using a sample 301 Pakistani non-financial listed for 2005–2014, we ...

Theory: This paper reformulates diversionary theory to take into account the effect of domestic structures on the propensity of leaders to use foreign policy to manipulate domestic politics. Hypotheses: The structure of domestic political institutions and levels of policy resources condition the willingness of leaders to use conflict involvement to manipulate domestic audiences. Method: Probit ...

Agents that learn about other agents and can exploit this information possess a distinct advantage in competitive situations. Games provide stylized adversarial environments to study agent learning strategies. Researchers have developed game playing programs that learn to play better from experience. We have developed a learning program that does not learn to play better, but learns to identify...

Adolescence is a period of increased risk experience and ever more often these occur online. The current study aims to investigate whether adolescents’ online and offline risk experiences are driven by the same general propensity to risks. Data from a representative study of N = 19,406 (50% girls) internet-using 11-16 year olds (M = 13.54, SD = 1.68) youth in Europe were subjected to the curren...