Summary. We propose the elastic net, a new regularization and variable selection method. Real world data and a simulation study show that the elastic net often outperforms the lasso, while enjoying a similar sparsity of representation. In addition, the elastic net encourages a grouping effect, where strongly correlated predictors tend to be in or out of the model together.The elastic net is particularly useful when the number of predictors (p) is much bigger than the number of observations (n). By contrast, the lasso is not a very satisfactory variable selection method in the

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Regularization and variable selection via the elastic net

For all its richness and potential for discovery, qualitative research has been critiqued as too often lacking in scholarly rigor. The authors summarize a systematic approach to new concept development and grounded theory articulation that is designed to bring “qualitative rigor” to the conduct and presentation of inductive research.

Seeking Qualitative Rigor in Inductive Research: Notes on the Gioia Methodology

Although problems of reliability and validity have been explored thoroughly by experimenters and other quantitative researchers, their treatment by ethnographers has been sporadic and haphazard. This article analyzes these constructs as defined and addressed by ethnographers. Issues of reliability and validity in ethnographic design are compared to their counterparts in experimental design. Threats to the credibility of ethnographic research are summarized and categorized from field study methodology. Strategies intended to enhance credibility are incorporated throughout the investigative process: study design, data collection, data analysis, and presentation of findings. Common approaches to resolving various categories of contamination are illustrated from the current literature in educational ethnography.

Problems of Reliability and Validity in Ethnographic Research

Partial Safety Factor Method Probabilistic Information Simple Reliability Index Geometric Reliability Index Generalized Reliability Index Transformation Sensitivity Analysis Monte Carlo Methods Load Combinations Statistical and Model Uncertainty Decision Philosophy Reliability of Existing Structures System Reliability Analysis Introduction to Process Descriptions.

https://chodor-projekt.net/wp-content/uploads/BiNSK/Literatura/Dilevsen,Madsen,%20Structural%20Reliability%20Methods%20(2007).pdf

Structural Reliability Methods

Generalizability is a major concern to those who do, and use, research. Statistical, sampling-based generalizability is well known, but methodologists have long been aware of conceptions of generalizability beyond the statistical. The purpose of this essay is to clarify the concept of generalizability by critically examining its nature, illustrating its use and misuse, and presenting a framework for classifying its different forms. The framework organizes the different forms into four types, which are defined by the distinction between empirical and theoretical kinds of statements. On the one hand, the framework affirms the bounds within which statistical, sampling-based generalizability is legitimate. On the other hand, the framework indicates ways in which researchers in information systems and other fields may properly lay claim to generalizability, and thereby broader relevance, even when their inquiry falls outside the bounds of sampling-based research.

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Generalizing Generalizability in Information Systems Research

The article by Walker, H. W. Degrees of Freedom. Journal of Educational Psychology. 31(4) (1940) 253-269, was transcribed from the original by Chris Olsen, George Washington High School, Cedar Rapids, Iowa. Chris has made every attempt to reproduce the "look and feel" of the article as well as the article itself, and did not attempt in any way to update the symbols to more "modern" notation. Three typographical errors were found in the paper. These errors are noted in the paragraphs below. The article, except for pagination and placement of diagrams, is as it originally appears. The transcribed pages are not numbered to avoid confusion with pagination in the original article.

http://www.nohsteachers.info/PCaso/AP_Statistics/PDFs/DegreesOfFreedom.pdf

H. M. Walker

Papers

Degrees of freedom.