Diversification and the Optimal Construction of Basis Portfolios

Nontrivial diversification possibilities arise when a factor model describes security returns. In this paper, we provide a comprehensive examination of the merits of various strategies for constructing basis portfolios that are, in principle, highly correlated with the common factors underlying security returns. Three main conclusions emerge from our study. First, increasing the number of securities included in the analysis dramatically improves basis portfolio performance. Our results indicate that factor models involving 750 securities provide markedly superior performance to those involving 30 or 250 securities. Second, comparatively efficient estimation procedures such as maximum likelihood and restricted maximum likelihood factor analysis (which imposes the APT mean restriction) significantly outperform the less efficient instrumental variables and principal components procedures that have been proposed in the literature. Third, a variant of the usual Fama-MacBeth portfolio formation procedure, which we call the minimum idiosyncratic risk portfolio formation procedure, outperformed the Fama-MacBeth procedure and proved equal to or better than more expensive quadratic programming procedures.

Spartan Daily, December 9, 1935

Volume 24, Issue 49https://scholarworks.sjsu.edu/spartandaily/2377/thumbnail.jp

Supporting English Language Learners in a Co-Taught Classroom through the Curriculum

Co-teaching is a common strategy used to support English Language Learners in the content classroom. However, English Language Learners can still struggle in these classrooms. Research has shown that co-teaching can be a benefit for students, but this takes collaboration between the content teacher and the English Language teacher to make the class accessible. This project was designed to take an existing English Language Arts curriculum and modify and adapt the curriculum to better meet the needs of English Language Learners. The WIDA 2020 standards and Grant Wiggins and Jay McTighe’s Understanding by Design were used as resources in developing the curriculum. The project involved modifying the English 11 curriculum currently in place in my school setting. The curriculum will be used in the co-taught English 11 class, but the curriculum planning and design can be used to modify the curriculums of other content classes in a collaborative effort between English Language teachers and the content teachers. The goal of the curriculum is to support the English Language Learners who need extra language support with the ultimate goal of helping students complete their required classes and graduate from high school

Embodiment of the Macbeth effect is mapped topographically onto the somatosensory cortex

The theory of embodied cognition claims that knowledge is represented in modal systems derived from perception. Recent behavioral studies found evidence for this hypothesis, for example, by linking moral purity with physical cleansing (the Macbeth effect). Neurophysiological approaches provided further support by showing an involvement of sensorimotor cortices for embodied metaphors. However, the exact role of this brain region for embodied cognitions remains to be cleared. Here we demonstrate that the involvement of the sensorimotor cortex for the embodied metaphor of moral-purity is somatotopically organized. Participants enacted in scenarios where they had to perform immoral or moral acts either with their mouths or their hands. Results showed that mouthwash products were particularly desirable after lying in a voice mail and hand wash products were particularly desirable after writing a lie, thus demonstrating that the moral-purity metaphor is specific to the sensorimotor modality involved in earlier immoral behavior. FMRI results of this interaction showed activation in sensorimotor cortices during the evaluation phase that was somatotopically organized with respect to preceding lying in a voice mail (mouth-area) or in a written note (hand-area). Thus, the results provide evidence for a central role of the sensorimotor cortices for embodied metaphors