New York University

About: New York University is a education organization based out in New York, New York, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 72380 authors who have published 165545 publications receiving 8334030 citations. The organization is also known as: NYU & University of the City of New York.

Monetary Policy Surprises, Credit Costs, and Economic Activity †

Abstract: We provide evidence on the transmission of monetary policy shocks in a setting with both economic and financial variables. We first show that shocks identified using high frequency surprises around policy announcements as external instruments produce responses in output and inflation that are typical in monetary VAR analysis. We also find, however, that the resulting "modest" movements in short rates lead to "large" movements in credit costs, which are due mainly to the reaction of both term premia and credit spreads. Finally, we show that forward guidance is important to the overall strength of policy transmission. (JEL E31, E32, E43, E44, E52, G01)

Why we (usually) don't have to worry about multiple comparisons

Abstract: Applied researchers often find themselves making statistical inferences in settings that would seem to require multiple comparisons adjustments. We challenge the Type I error paradigm that underlies these corrections. Moreover we posit that the problem of multiple comparisons can disappear entirely when viewed from a hierarchical Bayesian perspective. We propose building multilevel models in the settings where multiple comparisons arise. Multilevel models perform partial pooling (shifting estimates toward each other), whereas classical procedures typically keep the centers of intervals stationary, adjusting for multiple comparisons by making the intervals wider (or, equivalently, adjusting the p values corresponding to intervals of fixed width). Thus, multilevel models address the multiple comparisons problem and also yield more efficient estimates, especially in settings with low group-level variation, which is where multiple comparisons are a particular concern.

Calcium phosphate-based osteoinductive materials.

Abstract: This review focuses on calcium phosphate-based bone substitute materials that are used (or can be used) for teeth or bone replacement, bone repair, augmentation, or regeneration. This review will also include some properties of bone (e.g., interconnected porosity, biodegradability, bioactivity, osteoconductivity) that are being mimicked in the manufacture of calcium phosphate-based biomaterials and some of the reported factors and strategies that can make the calcium phosphate-based biomaterials acquire osteoinductive properties. Archaeological findings showed that attempts to replace missing teeth date back to the prehistoric period. The materials used then included shells, corals, ivory (from elephant tusks), metals, and human (from corpses) and animal bones. Because of the practice of cremation in many societies, not much is known about prehistoric materials used to replace bones lost to accident or disease. Presently, autografts (bones obtained from another anatomic site in the same subject) remain the gold standard for bone repair, substitution, and augmentation followed by allografts (bones from another subject, such as processed cadaver bones). Autografts and allografts while having the important advantage of being osteogenic or osteoinductive (i.e., inducing bone formation), suffer from several disadvantages. With autografts the drawbacks include additional expense and trauma to the patient, possibility of donor site morbidity, and limited availability. In the case of allografts, in addition to limited supply and high cost, potential viral transmission and immunogenicity are of serious concern. Because of the high cost and limited availability of autografts and allografts, there is a great need to develop synthetic alternative biomaterials for bone replacement, repair, and augmentation. Current commercial substitute materials to replace or repair teeth and bones include metals, polymers (natural or synthetic), corals, human bones (processed cadaver bones), animal bones (processed cow bones), corals and coral derived, synthetic ceramics (calcium phosphates, calcium sulfates, calcium carbonate, bioactive glasses), and composites. It is interesting to note that several of the materials used in prehistoric times are similar to the materials used presently (e.g., coral and coral derived, animal bone derived, metals). Generally, depending on the ability to stimulate bone tissue, materials for tooth or bone repair or replacement are classified as bioinert or bioactive. Bioinert materials do not stimulate bone formation but instead stimulate formation of fibrous tissue and therefore do not directly bond to bone and thus form a weak biomaterial-bone interface. Bioactive materials stimulate bone tissue formation and therefore directly bond with bone and thus form a uniquely strong biomaterial-bone interface. Bioinert materials include metals (e.g., titanium or titanium alloys, stainless steel, cobalt-chromium, Co-Cr, alloys), some synthetic polymers (e.g., PEEK, Teflon-type), and some ceramics (e.g., alumina, * To whom correspondence should be addressed. Phone: (212) 998-9580. Fax: (212) 995-4244. E-mail: rzl1@nyu.edu. Racquel Zapanta LeGeros received her Ph.D. degree from New York University. She is currently a Professor and Associate Chair of the Department of Biomaterials and Biomimetics at New York University College of Dentistry. Her pioneering work was on substitution in the apatite structure and effect on properties. Her research interests includes biologic and synthetic apatites and related calcium phosphates, calcium phosphatebased biomaterials in the form of granules, scaffolds, cements, and coatings, and implant surface modifications. Her current research is on the development of calcium phosphate-based biomaterial for prevention of bone loss induced by diseases (e.g., osteoporosis), therapy (e.g., radiation), condition (e.g., mineral deficiency, immobility), and recovery of bone loss. She is married to Dr. John P. LeGeros and mother of Bernard, David, Katherine, and Alessandra. Chem. Rev. 2008, 108, 4742–4753 4742

Inside the Family Firm: The Role of Families in Succession Decisions and Performance

Abstract: This paper uses a unique dataset from Denmark to investigate (1) the role of family characteristics in corporate decision making, and (2) the consequences of these decisions on firm performance. We focus on the decision to appoint either a family or an external chief executive officer (CEO). We show that a departing CEO’s family characteristics have a strong predictive power in explaining CEO succession decisions: family CEOs are more frequently selected the larger the size of the family, the higher the ratio of male children and when the departing CEOs had only had one spouse. We then analyze the impact of family successions on performance. We overcome endogeneity and omitted variables problems of previous papers in the literature by using the gender of a departing CEO’s first-born child as an instrumental variable (IV) for family successions. This is a plausible IV as male first-child family firms are more likely to pass on control to a family CEO than female first-child firms, but the gender of the first child is unlikely to affect firms’ performance. We find that family successions have a dramatic negative causal impact on firm performance: profitability on assets falls by at least 6 percentage points around CEO transitions. These estimates are significantly larger than those obtained using ordinary least squares. Finally, our findings demonstrate that professional non-family CEOs provide extremely valuable services to the organizations they work for.