We examine a database of over 700 spawner-recruitment series to search for parameters that are constant, or nearly so, at the level of a species or above. We find that the number of spawners produced per spawner each year at low populations, i.e., the maximum annual reproductive rate, is relatively constant within species and that there is relatively little variation among species. This quantity can be interpreted as a standardized slope at the origin of a spawner-recruitment function. We employ variance components models that assume that the log of the standardized slope at the origin is a normal random variable. This approach allows improved estimates of spawner-recruitment parameters, estimation of empirical prior distributions for Bayesian analysis, estimation of the biological limits of fishing, calculation of the maximum sustainable yield, and impact assessment of dams and pollution.

Models of population dynamics in which per capita reproductive success declines at low population levels (variously known as depensation, the Allee effect, and inverse density-dependence) predict that populations can have multiple equilibria and may suddenly shift from one equilibrium to another. If such depensatory dynamics exist, reduced mortality may be insufficient to allow recovery of a population after abundance has been severely reduced by harvesting. Estimates of spawner abundance and number of surviving progeny for 128 fish stocks indicated only 3 stocks with significant depensation. Estimates of the statistical power of the tests strengthen the conclusion that depensatory dynamics are not apparent for fish populations at the levels studied.

Integrated Product Development (IPD) creates overlap and interaction between activities in the new product development process and, because this increases the need to coordinate, compensates through other aspects of the new product development process (e.g., integrated tools), product definitions (e.g., incremental development), organizational context (e.g., reduced task specialization), and teaming (e.g., cross-functional teams). Since IPD has become an important new standard for managing new product development, this paper's general aim is to evaluate the research that has been conducted on it. Our three specific objectives include first critiquing the IPD literature by identifying problems with empirical research and recommending solutions. There are concerns about the overall approach, conceptualizing and operationalizing IPD characteristics, and selecting performance objectives. Second, we conduct a meta-analysis to evaluate relationships between specific IPD characteristics and project performance. We indicate where relationships do or do not exist and identify variables that may moderate these relationships. Third, we offer suggestions for extending IPD research into studies of (a) the hierarchy of teams working on a project, (b) one company managing a portfolio of projects over time, and (c) two or more firms collaborating in a strategic alliance.integrated product development, concurrent engineering, new product development, cross-functional teams, project management, literature review, meta-analysis

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