Fuzzy sets and social research

four in-depth methodological discussions of the use of fuzzy sets in social research. They have in common that they confront and compare fuzzy set methods with mainstream techniques. These contributions should not be read as introductions to fuzzy set analysis (see Smithson 1987; Ragin 2000) but as attempts to validate this new methodology and demonstrate some of its strengths by comparing it with estab-lished approaches. In brief, fuzzy sets extend Boolean or “crisp ” sets by permitting membership scores in the interval between 0 and 1. With crisp sets, cases are perceived only as members or nonmembers of a set. The problem is that many core concepts in social research are best under-stood as graded sets. Examples include such dichotomies as coordi-nated versus uncoordinated economies, national versus international politics, the public versus the private sector, states versus markets, consensus versus majoritarian systems, democratic versus nondemo-cratic, federal versus nonfederal, employed versus unemployed, male versus female, high versus low, established versus nonestablished, rich versus poor, and so on (see Pennings 2003). At a theoretical level, most researchers are fully aware of the problematic aspects of using these concepts as simple dichotomies. But this awareness has not been translated into the application of methodologies that are fully equipped to study diversity and complexity in a set-theoretic manner. Fuzzy sets can help social scientists conceptualize social and political phenomena as sets with imprecise boundaries betwee

Integrative genomic analysis identifies ancestry-related expression quantitative trait loci on DNA polymerase β and supports the association of genetic ancestry with survival disparities in head and neck squamous cell carcinoma

BACKGROUND: African Americans with head and neck squamous cell carcinoma (HNSCC) have a lower survival rate than whites. This study investigated the functional importance of ancestry-informative single-nucleotide polymorphisms (SNPs) in HNSCC and also examined the effect of functionally important genetic elements on racial disparities in HNSCC survival. METHODS: Ancestry-informative SNPs, RNA sequencing, methylation, and copy number variation data for 316 oral cavity and laryngeal cancer patients were analyzed across 178 DNA repair genes. The results of expression quantitative trait locus (eQTL) analyses were also replicated with a Gene Expression Omnibus (GEO) data set. The effects of eQTLs on overall survival (OS) and disease-free survival (DFS) were evaluated. RESULTS: Five ancestry-related SNPs were identified as cis-eQTLs in the DNA polymerase β (POLB) gene (false discovery rate [FDR] < 0.01). The homozygous/heterozygous genotypes containing the African allele showed higher POLB expression than the homozygous white allele genotype (P < .001). A replication study using a GEO data set validated all 5 eQTLs and also showed a statistically significant difference in POLB expression based on genetic ancestry (P = .002). An association was observed between these eQTLs and OS (P < .037; FDR < 0.0363) as well as DFS (P = .018 to .0629; FDR < 0.079) for oral cavity and laryngeal cancer patients treated with platinum-based chemotherapy and/or radiotherapy. Genotypes containing the African allele were associated with poor OS/DFS in comparison with homozygous genotypes harboring the white allele. CONCLUSIONS: Analyses show that ancestry-related alleles could act as eQTLs in HNSCC and support the association of ancestry-related genetic factors with survival disparities in patients diagnosed with oral cavity and laryngeal cancer. Cancer 2017;123:849-60. © 2016 American Cancer Society

Redefining Case Study

Abstract: In this paper the authors propose a more precise and encompass-ing definition of case study than is usually found. They support their defini-tion by clarifying that case study is neither a method nor a methodology nor a research design as suggested by others. They use a case study prototype of their own design to propose common properties of case study and demon-strate how these properties support their definition. Next, they present sev-eral living myths about case study and refute them in relation to their definition. Finally, they discuss the interplay between the terms case study and unit of analysis to further delineate their definition of case study. The target audiences for this paper include case study researchers, research de-sign and methods instructors, and graduate students interested in case study research