Derivatives of the Incomplete Beta Function

The incomplete beta function is defined as where Beta(p, q) is the beta function. Dutka (1981) gave a history of the development and numerical evaluation of this function. In this article, an algorithm for computing first and second derivatives of Ix,p,q with respect to p and q is described. The algorithm is useful, for example, when fitting parameters to a censored beta, truncated beta, or a truncated beta-binomial model.

Simulating Gender Stratification

The simulation of promotional competitions in corporations described herein allows comparisons of suggested reasons for the paucity of women in the highest level of corporate management. Runs with small, medium and large-sized companies all give similar results. The strongest effect is evidenced when men are given a bonus in performance evaluations. Similar stratification is observed when men's scores are drawn from a distribution with increased variance. Other explanations (increased female attrition, career delays for women, line-staff divisions, and external labor market) do not, by themselves produce strong gender stratification, but could add to that produced by biased evaluations.Glass Ceiling, Gender Stratification, Promotion, Performance Evaluation Bias, Computer Simulation

Financial Regulation in a Global Market Place: Report of the Duke Global Capital Markets Roundtable

This report summarizes the discussion of over sixty participants in the April 30, 2007 roundtable convened by the Duke Global Capital Market Center. The roundtable focused on important issues posed by the increasing globalization of securities offerings and trading markets. The invited participants were selected because of their broad experience as regulators, practitioners, or academics in international securities transactions, assuring a wide spectrum of views on the future direction of regulation

Summary of Roundtable Discussions Regarding the Future Content of the U.S. Securities Laws

On Apr 8-9, 1999, more than sixty securities lawyers, regulators and academics participated in a roundtable discussion in Washington DC on what should be the future content of the US securities laws. A summary of the discussions is presented

A Theory and Test of Credit Rationing: Comment

This article presents the authors\u27 comments on the paper A Theory and Test of Credit Rationing, by Dwight Jaffee and F. Modigliani, published in the December 1969 issue of the American Economic Review journal. One frequently encounters the casual empirical conclusion that some consumers and firms are not able to borrow as much as they would like at market rates of interest. The existence of these rejected offers to pay market rates of interest is then said to constitute credit rationing. Marshall Freimer and Myron Gordon, in addition to Jaffee and Modigliani, assume that rejected market interest rate offers exist and then attempt to explain why lenders might engage in such credit rationing. Our analysis begins by questioning the prevalent identification of credit rationing with rejected offers to pay market rates of interest. This concept of credit rationing is apparently derived by analogy with the theory of commodity markets under certainty. In that theory, any economic agent who makes an effective demand for a commodity, that is, who offers to pay its market price, is subject to nonprice commodity rationing if his demand is not supplied. The common extension of this conclusion to credit markets is that any economic agent who offers to pay the market rate of interest on some type of loan is subject to credit rationing if his demand for credit is not supplied. We argue that this concept of credit rationing is not useful because it is based on an inappropriate implicit assumption that an offer to pay the market rate of interest on a loan constitutes an effective demand for credit

Derivatives of the Incomplete Beta Function

The incomplete beta function is defined as where Beta(p, q) is the beta function. Dutka (1981) gave a history of the development and numerical evaluation of this function. In this article, an algorithm for computing first and second derivatives of Ix,p,q with respect to p and q is described. The algorithm is useful, for example, when fitting parameters to a censored beta, truncated beta, or a truncated beta-binomial model

Histopathologic evaluation of the effects of four calcium hydroxide liners on monkey pulps

Pulpal response of four calcium hydroxide liners, MPC 10®, MPC 12®, Dycal® and Pulpdent® were tested on primary and permanent teeth with zinc oxide and eugenol (ZOE) and silicate as controls. Responses of the pulps were evaluated in Rhesus monkeys, utilizing Class V cavity preparations at 3 days, 5 and 8 weeks. An equivalent number of anterior and posterior teeth were studied for all compounds. The Ca(OH) 2 liners, zinc oxide and eugenol (ZOE) and silicate controls were placed in 80 primary and 80 permanent teeth. Following perfusions the teeth were prepared utilizing routine histological procedures. The 3 day response of the calcium hydroxides was moderate with some disruption in the odontoblasts, vacuolization and mild inflammation underlying the cavity except Pulpdent which was more severe. At 5 weeks a decrease in inflammatory response and the formation of reparative dentin was similar for all calcium hydroxides tested at this time period. At 8 weeks more reparative dentin was noted with slight to moderate pulpal responses. At all time periods ZOE produced the least pulpal response while silicate produced the most severe response at 5 and 8 weeks. This study reports the biological responses of four calcium hydroxide compounds used as cavity liners in non-exposures in a series of primary and permanent teeth of monkeys using ZOE and silicate as controls. Responses to the four Ca(OH) 2 compounds were moderate for all the experimental compounds except Pulpdent which was more severe at the early time period tested. ZOE produced a milder and silicate a severe response at all periods. All of these compounds were placed by random selection in anterior and posterior teeth of both arches and five teeth were evaluated in both primary and permanent teeth at 3 days, 5 and 8 weeks.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74743/1/j.1600-0714.1976.tb01759.x.pd

Histopathologic Evaluation of three Ultraviolet-Activated Composite Resins on Monkey pulps

The pulpal responses of three ultraviolet-activated composite resins, Nuva-Fil®, Experimental UV #1® and Experimental UV #2®, were tested on adult monkey teeth using silicate and zinc oxide eugenol (ZOE) as positive and negative controls. All materials were placed in Class V cavity preparations in Rhesus monkey teeth using approximately 48 anterior and 63 posterior teeth of both the maxillary and mandibular arches. A total of 111 teeth were utilized and all materials were evaluated at 3 days, 5 and 8 weeks. Following left ventricular perfusion, the teeth were prepared for microscopic evaluation using routine histological procedures. The 3-day pulpal response of all the ultraviolet-activated composites was slight with some disruption and vacuolization in the odontoblastic layer and a slight inflammatory response. At 5 weeks there was a reduction of the inflammatory response and the formation of reparative dentin was noted for all ultraviolet composites. The 8-week pulp response was slight, characterized by a minimal inflammatory response adjacent to the zone of reparative dentin. Generally, ZOE produced the mildest response while silicate produced the most severe response at the three time intervals.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74732/1/j.1600-0714.1977.tb01797.x.pd