Shaped extensions of singular spectrum analysis

Extensions of singular spectrum analysis (SSA) for processing of non-rectangular images and time series with gaps are considered. A circular version is suggested, which allows application of the method to the data given on a circle or on a cylinder, e.g. cylindrical projection of a 3D ellipsoid. The constructed Shaped SSA method with planar or circular topology is able to produce low-rank approximations for images of complex shapes. Together with Shaped SSA, a shaped version of the subspace-based ESPRIT method for frequency estimation is developed. Examples of 2D circular SSA and 2D Shaped ESPRIT are presented

Pricing of Defaultable Securities under Stochastic Interest

We reduce the problem of pricing continuously monitored defaultable securities (namely, barrier type options, corporate debts) under a stochastic interest rate framework to calculations of boundary crossing probabilities (BCP) for Brownian Motion (BM) with stochastic boundaries. For the case when the interest rate is governed by linear stochastic equation (Vasicek model) we suggest a numerical algorithm for calculation of BCP based on a piece-wise linear approximation for the stochastic boundaries. We also provide an estimation for a rate of convergence of the suggested approximation as a function of number of nodes and illustrate the results by numerical examples.

The Longitudinal Effects of STEM Identity and Gender on Flourishing and Achievement in College Physics

Background. Drawing on social identity theory and positive psychology, this study investigated women’s responses to the social environment of physics classrooms. It also investigated STEM identity and gender disparities on academic achievement and flourishing in an undergraduate introductory physics course for STEM majors. 160 undergraduate students enrolled in an introductory physics course were administered a baseline survey with self-report measures on course belonging, physics identification, flourishing, and demographics at the beginning of the course and a post-survey at the end of the academic term. Students also completed force concept inventories and physics course grades were obtained from the registrar. Results. Women reported less course belonging and less physics identification than men. Physics identification and grades evidenced a longitudinal bidirectional relationship for all students (regardless of gender) such that when controlling for baseline physics knowledge: (a) students with higher physics identification were more likely to earn higher grades; and (b) students with higher grades evidenced more physics identification at the end of the term. Men scored higher on the force concept inventory than women, although no gender disparities emerged for course grades. For women, higher physics (versus lower) identification was associated with more positive changes in flourishing over the course of the term. High-identifying men showed the opposite pattern: negative change in flourishing was more strongly associated with high identifiers than low identifiers. Conclusions. Overall, this study underlines gender disparities in physics both in terms of belonging and physics knowledge. It suggests that strong STEM identity may be associated with academic performance and flourishing in undergraduate physics courses at the end of the term, particularly for women. A number of avenues for future research are discussed

Inference in Predictive Quantile Regressions

This paper studies inference in predictive quantile regressions when the predictive regressor has a near-unit root. We derive asymptotic distributions for the quantile regression estimator and its heteroskedasticity and autocorrelation consistent (HAC) t-statistic in terms of functionals of Ornstein-Uhlenbeck processes. We then propose a switching-fully modified (FM) predictive test for quantile predictability with persistent regressors. The proposed test employs an FM style correction with a Bonferroni bound for the local-to-unity parameter when the predictor has a near unit root. It switches to a standard predictive quantile regression test with a slightly conservative critical value when the largest root of the predictor lies in the stationary range. Simulations indicate that the test has reliable size in small samples and particularly good power when the predictor is persistent and endogenous, i.e., when the predictive regression problem is most acute. We employ this new methodology to test the ability of three commonly employed, highly persistent and endogenous lagged valuation regressors - the dividend price ratio, earnings price ratio, and book to market ratio - to predict the median, shoulders, and tails of the stock return distribution

Professor Walks into a Bar: Using Humor and Q-Score to Determine Instructor and Department Appeal

Building on existing research on humor in the classroom, the authors propose a research design that examines the effect of humor on a professor's effectiveness in the classroom. The concept of Q-Score is applied to academia, which is a popular rating used by advertisers to measure source attractiveness and determine celebrity appeal. Several factors leading to teaching effectiveness and “favorite prof” status are explored in addition to overall effects of humor in the classroom. This study combines evaluations from popular student-viewed websites, student evaluations, and a Humor Orientation scale. An awareness and application of this metric can assist professors in marketing themselves, the discipline, and the major

Consumer responses to hedonic food products: Healthy cake or indulgent cake? Could dialecticism be the answer?

Marketing of indulgent food products with healthy claims (e.g., healthy cake) is challenging, and studies explaining consumer responses to such products are limited. This research addresses this limitation by focusing on an unexamined driver of responses to vice food products marketed as more healthy—dialectical thinking. Three experimental studies using samples from online panels show that dialecticism has a positive effect on consumers' evaluations of such products when primed within a predominantly non-dialectical culture, across cultures with different levels of dialecticism, and as an individual difference. In all three studies experienced discomfort mediates this effect. This research contributes to extant literature by (1) identifying the role of dialecticism in mitigating consumers' aversion to vice food products with healthy claims, (2) confirming the effects of dialecticism at both cultural and individual levels, and (3) highlighting the managerial relevance of dialecticism