Corporate finance research requires close consideration of the assumptions underlying the econometric models applied to test hypotheses. This is partly because, as the field has evolved, more complex relationships have been examined, some of which pose problems of endogeneity. Endogeneity is one problem that violates the assumptions of the CLRM. It is so central that this book devotes a whole chapter to discussing it. The chapter covers the sources of endogeneity bias and the most commonly used methods that can be applied to cross-sectional data to deal with the endogeneity problem in corporate finance. These methods cover two-stage least squares (so-called IV approach), treatment effects, matching techniques, and regression discontinuity design (RDD). An application is provided for an IV approach and an RDD approach. The chapter ends with an application of the most common methods to real data, lab work, and a mini case study.

The chapter focuses on education as a social variable. It critically reviews classical approaches and suggests news ways of integrating education as a variable in sociolinguistic research in Arabic. These approaches are illustrated by examples from qualitative and quatitative studies.