Distribution of angles between unit vectors and the multiple comparison problem for unit vectors

We suppose that L x i = Fq(μi, KiK) for i=1,...,p, where the independent Fisher distributions on the unit sphere in Rq have modal vectors μi and known concentrations KiK, where K will be large—in fact, to obtain asymptotic distributions, we will let K tend to infinity. The term x'iXj=cos 0ij estimates cos 0ij= μiμy. The asymptotic joint distribution of the terms will be studied when all the vectors μi μ are distinct, and for the special case when all the vectors μi=μ, so that all the terms are zero. These very different results have a variety of applications as well as being interesting in themselves. One of these applications is the 'multiple comparisons problem' for unit vectors. However, it was found necessary to give here a different way of solving this problem.     

A decision support system for banks

Just recently, information systems with rather unique characteristics have begun to emerge. These systems usually referred to as Decision Support Systems, feature decision models, a data base and the decision maker as subsystems and are specifically oriented to supporting decision making. This article examines Decision Support Systems and their application to banks.     

Identifying Technology Spillovers and Product Market Rivalry

The impact of R&D on growth through spillovers has been a major topic of economic research over the last thirty years. A central problem in the literature is that firm performance is affected by two countervailing “spillovers” : a positive effect from technology (knowledge) spillovers and a negative business stealing effects from product market rivals. We develop a general framework incorporating these two types of spillovers and implement this model using measures of a firm's position in technology space and productmarket space. Using panel data on U.S. firms, we show that technology spillovers quantitatively dominate, so that the gross social returns to R&D are at least twice as high as the private returns. We identify the causal effect of R&D spillovers by using changes in federal and state tax incentives for R&D. We also find that smaller firms generate lower social returns to R&D because they operate more in technological niches. Finally, we detail the desirable properties of an ideal spillover measure and how existing approaches, including our new Mahalanobis measure, compare to these criteria.     

Determining Process Death Based on Censored Activity Data

This article addresses the problem of estimating the time of apparent death in a binary stochastic process. We show that, when only censored data are available, a fitted logistic regression model may estimate the time of death incorrectly. We improve this estimation by utilizing discrete-event simulation to produce simulated complete time series data. The proposed methodology may be applied to situations where time of death cannot be formally determined and has to be estimated based on prolonged inactivity. As an illustration, we use observed monthly activity patterns from 300 real Open Source Software development projects sampled from Sourceforge.net.     

ASTRONOMICS IN ACTION: THE GRADUATE EARNINGS PREMIUM AND THE DRAGON EFFECT IN SINGAPORE

This paper investigates the return to university education in Singapore using a new estimation strategy related to Chinese traditions where children born in the Year of the Dragon are believed to be superior. Because parents might time the arrival of their offspring on a Dragon year, this causes the Dragon cohort to be larger and university entry to be more competitive. First, we find evidence of a negative “Dragon effect” on university educational attainment. Then, using it as an estimation strategy, we find that university education has a ceteris paribus effect of raising earnings by at least 50% on average. (JEL I21, C26, J30)     

Where to from here? Blue passports,family, career—and Donald Trump

Abstract

In this essay, we offer our stories of family and migration under a Donald Trump presidency. We are a lesbian couple; one of us is a citizen of the United States while the other is a citizen of a Muslim country. We use autoethnographic methods to explore and interrogate our “messy and fabulous” journey of liminality; our journey of belonging and exclusion, where we grapple with issues related to sexuality, family, career, and citizenship. Our “voices” are used both individually and in unison, to highlight our intersectional and relational selves. We intend this work to contribute to the many ways we can better understand and appreciate the bountiful and colorful vistas of lesbian families’ migrant experiences.     

Migration and the senses

Recent scholarship in the sociological subfields of culture and immigration offers several promising directions for studying how people experience the world in embodied ways and move through and across boundaries. Yet, the lack of overlap between fields has left numerous theoretical angles unexplored. In this review, I consider the limited existing scholarship at the intersection of migration and the senses. I discuss literature on the role of sensation during three critical moments of migration: movement, encounter, and return. These moments highlight the sensorially dislocating nature of travel, the felt politics of inclusion and exclusion, and the transporting power of embodied memories. These works dive deep into the everyday realities of bodies on the move that public and academic discourse has previously ignored. I conclude by briefly outlining exciting new directions to expand work connecting migration and the senses and suggest that we begin to explore globalized migrant sensibilities.