Auditing, Statistical auditing, Jackknifed ratio estimation, Accounting population

When portfolio optimization is implemented using the historical characteristics of security returns, estimation error can degrade the desirable properties of the investment portfolio that is selected. Given the problem of estimation risk, it is natural to formulate rules of portfolio selection within a Bayesian framework. In this framework, portfolio selection is based on maximization of expected utility conditioned on the predictive distribution of security returns. Most researchers have addressed the problem of estimation risk by asserting a noninformative diffuse prior that reduces the detrimental effect of estimation risk, but does not directly reduce estimation error. Portfolio performance can be improved by specifying an informative prior that reduces estimation error. An informative prior that all securities have identical expected returns, variances, and pairwise correlation coefficients is asserted. This informative prior reduces estimation error by drawing the posterior estimates of each security's expected return, variance, and pairwise correlation coefficients toward the average return, average variance, and average correlation coefficient, respectively, of all the securities in the population. The amount that each of these parameters is drawn toward its grand mean depends upon the degree to which the sample is consistent with the informative prior. This empirical Bayes method is shown to select portfolios whose performance is superior to that achieved, given the assumption of a noninformative prior or by using classical sample estimates.

Do new issues of seasoned securities cause significant price movements in the neighborhood of the issue day? This paper presents an empirical comparison of three competing hypotheses: the SEC view that a new issue causes a permanent price decline; the underwriter view that there is only a temporary price decline during the distribution period; and the efficient market hypothesis (EMH) that implies the absence of any price effects. Several empirical tests of the competing hypotheses using data on new issues of utility stocks traded on the NYSE reject the SEC and underwriter views in favor of the EMH.

Do new issues of seasoned securities cause significant price movements in the neighborhood of the issue day? This paper presents an empirical comparison of three competing hypotheses: the SEC view that a new issue causes a permanent price decline; the underwriter view that there is only a temporary price decline during the distribution period; and the efficient market hypothesis (EMH) that implies the absence of any price effects. Several empirical tests of the competing hypotheses using data on new issues of utility stocks traded on the NYSE reject the SEC and underwriter views in favor of the EMH.

This paper presents the results of an empirical investigation of whether there is any difference in the cost incurred by public utilities if they issue new equity through a negotiated or competitive underwriting. We conclude that the expected cost of a competitive offer is less than the expected cost of a negotiated offer, but that the variance of the cost is substantially greater with a competitive offer. These results are interesting because most public utilities use negotiated underwriting unless forced by regulation to use competitive offers. This paper is also an addition to the growing agency theory literature.