Abnormal returns (market model prediction errors) are the subject of many event studies in accounting and finance literature. Conditional on the event of interest, researchers have recently used cross-sectional regressions to examine relations between abnormal returns and firm specific variables. This paper demostrates that non-constant variences and covariances in market model residuals across firms introduced bias in the estimated slope coefficients of the independent variables, i.e., the expected signs of the estimated slope coefficients can be predicted a priori. A method is develope to removed the bias in the estimated slope coefficiets and is found to be effective. This method explicitly takes the dependence among abnormal returns across firms into account. Methods that assume abnormal returns across firms to be independent do not control for such bias.

This paper develops two distinct models for studying inventory systems with continuous production and perishable items. The perishable items have a deterministic usable life after which they must be outdated. For each of the models, analytical expressions derived from queueing theory, are found for the steady-state distribution of system inventory. Knowledge of this steady-state behavior may be used for evaluation of system performance, and for consideration of alternatives for improving system performance. Both models assume that inventory is replenished by a continuous production process. The first model, assuming continuous inventory units, has Poisson demand requests with the size of each request distributed as an exponential random variable. The second model has Poisson demand requests with all demands being for a single unit. The analysis for both models exploits the similarity of the inventory system with a single-server queueing system.

The subjective evaluation of an organization's effectiveness (or competence) by its top executives was found to be an excellent predictor of the subsequent survival and growth of the organization. Although financial criteria of profit and revenue growth were the best predictors, several nonfinancial indicators also were significant.

Organizations use planning methods to improve performance factors associated with their products, services, and operations, but practitioners have few guides for selecting a method that seems best for a particular project type. This paper constructs planning methods by using technique strings that span the creative stages of planning. Hybrid planning methods, made up of technique strings, are matched to eight project types, defined by the sponsor's expectations for quality, acceptance, and/or innovation in the plan.

The article reviews the book ?Information, Organization, and Power,? by Dale E. Zand.

Information evaluation, Information systems, Group decision making, Group performance

Asset valuation, Replacement costs, Fixed asset lives, Depreciation