Observational Learning in the Jumping Spider \u3ci\u3ePhidippus audax\u3c/i\u3e

Observational learning is a complex form of learning most frequently studied in social vertebrates. However, evidence for social learning exists in several invertebrate species Evidence of invertebrate observational learning also exists, though to a lesser extent. This study addresses observational learning in a jumping spider (Phidippus audax) through video playback. My results suggest that while observational learning is occurring, the exact mechanism in use remains unclear. Spiders that saw a conspecific satiate itself on a prey item readily attacked a similar prey item when exposed to a live prey item. However, spiders exposed to a conspecific rejecting or in the absence of a prey item were much more cautious when exposed to a live prey item. While virtually all spiders did eventually attack, a significant increase was found in the latency to the attack. No other groups demonstrated deviated from the behavior of the control group. My data suggest that observational learning may be present in a more diverse array of taxa than is held in traditional views of social learning, including highly asocial invertebrates such as spiders. Advisor: Rick A. Bevin

Flutter suppression using eigenspace freedoms to meet requirements

A constrained optimization methodology has been developed which allows specific use of eigensystem freedoms to meet design requirements. A subset of the available eigenvector freedoms was employed. The eigenvector freedoms associated with a particular closed-loop eigenvalue are coefficients of basis vectors which span the subspace in which that closed-loop vector must lie. Design requirements are included as a vector of inequality constraints. The procedure was successfully applied to develop an unscheduled controller which stabilizes symmetric flutter of an aeroelastic vehicle to a dynamic pressure 44 percent above the open-loop flutter point. The design process proceeded from full-state feedback to the inclusion of a full-order observer to the selection of an eighth-order controller which preserved the full-state sensitivity characteristics. Only a subset of the design freedoms was utilized (i.e., assuming full-state feedback only four out of 26 eigenvectors were used, and no variations were made in the closed-loop eigenvalues). Utilization of additional eigensystem freedoms could further improve the controller

EFFECTS OF EEP ON CANADIAN/UNITED STATES WHEAT TRADE

Agricultural and Food Policy, International Relations/Trade,

Market Power in Outputs and Inputs: An Empirical Application to Banking

This paper provides evidence on the empirical separability of input and output market imperfections. We specify a model of banking competition and simultaneously estimate bank conduct in output (loan) and input (deposit) markets. Our results suggest that firms display some degree of noncompetitive behavior in both the loan and the deposit markets. Moreover, we find that the input side and the output side are empirically separable, that is the measurement of market power on one side of the market is not affected by assuming that the other side of the market is perfectly competitive. Our results suggest that empirical studies of market power that concentrate on either the input side or the output side, are not subject to significant misspecification error. ZUSAMMENFASSUNG - (Marktmacht auf Input- und Outputmärkten: Eine Empirische Anwendung auf den Bankensektor) Der Aufsatz untersucht den Zusammenhang von Unvollkommenheiten auf Input- und auf Outputmärkten. Im Rahmen eines Wettbewerbsmodells für den Bankensektor wird die Wechselwirkung zwischen Outputmarkt, d.h. bei der Kreditvergabe, und Inputmarkt (Geldanlage) empirisch untersucht. Die Ergebnisse zeigen, dass Banken auf beiden Seiten des Marktes eine gewisse Marktmacht ausüben können. Allerdings ist die Wechselwirkung begrenzt, sodass eine separate Betrachtungsweise von Input- und Outputmärkten möglich ist. Dies bedeutet wiederum, dass empirische Untersuchungen, die jeweils nur eine Seite des Marktes analysieren, keinen signifikanten Verzerrungen unterliegen.Measuring Market Power, Banking

WELFARE EFFECTS OF FISHERY POLICIES: NATIVE AMERICAN TREATY RIGHTS AND RECREATIONAL SALMON FISHING

Severe declines in Pacific Northwest salmon stocks, coupled with increasing recreational demands, and judicial decisions supporting Native American fishing rights create challenges for fishery agencies. This article explores the welfare effects on recreational anglers of alternative salmon allocation policies to meet Native American treaty rights. A discrete choice random utility model, coupled with a Poisson trip frequency model, is used to analyze these welfare effects. The model is fit to survey data from the Willamette River spring chinook fishery, an important recreational fishery in Oregon. Management options have dramatically different welfare effects.Resource /Energy Economics and Policy,

Measuring Market Power in Input and Output Markets: An Empirical Application to Banking

This paper develops and estimates a model of market conduct in the US banking industry during the 1990s. Competition in both output and factor markets is measured in a static Cournot model in the spirit of Bresnahan (1989), Shaffer (1991,1994a), Neven and Roeller (1997), and others. Banks can exert market power in loans as well as in deposit markets. Previous studies on banking competition center on the structure conduct hypothesis, where reduced form models with market concentration measures are used to estimate the degree of competition. We consider a disaggregated structural model of bank loan markets, where bank's competitive behavior is measured in input and output markets. Our results indicate that the standard model which measures only output market behavior is potentially biased.

Reliability and performance evaluation of systems containing embedded rule-based expert systems

A method for evaluating the reliability of real-time systems containing embedded rule-based expert systems is proposed and investigated. It is a three stage technique that addresses the impact of knowledge-base uncertainties on the performance of expert systems. In the first stage, a Markov reliability model of the system is developed which identifies the key performance parameters of the expert system. In the second stage, the evaluation method is used to determine the values of the expert system's key performance parameters. The performance parameters can be evaluated directly by using a probabilistic model of uncertainties in the knowledge-base or by using sensitivity analyses. In the third and final state, the performance parameters of the expert system are combined with performance parameters for other system components and subsystems to evaluate the reliability and performance of the complete system. The evaluation method is demonstrated in the context of a simple expert system used to supervise the performances of an FDI algorithm associated with an aircraft longitudinal flight-control system

On the mechanical properties of N-functionalised dipeptide gels

The properties of a hydrogel are controlled by the underlying network that immobilizes the solvent. For gels formed by the self-assembly of a small molecule, it is common to show the primary fibres that entangle to form the network by microscopy, but it is difficult to access information about the network. One approach to understand the network is to examine the effect of the concentration on the rheological properties, such that G cx, where G is the storage modulus and c is the concentration. A number of reports link the exponent x to a specific type of network. Here, we discuss a small library of gels formed using functionalized dipeptides, and describe the underlying networks of these gels, using microscopy, small angle scattering and rheology. We show that apparently different networks can give very similar values of x

Economic profile of Florida's marine life industry

The marine life industry in Florida is defined as the harvest of live marine specimens (fish and invertebrate species including plants, live rock and sand, and small “critters”) for commercial use, primarily aquariums. This paper summarizes data collected on the industry since 1990, including total landings, revenues, and trends over time. Regional analysis shows where the primary collecting areas are located in Florida. Seasonal analysis shows when the majority of landings occur within the year. Statistics on the number of participants by type (i.e., collector versus wholesaler) provide insight into the size of the industry. Trends are evaluated in terms of changes across the 9-year period from 1990 to 1998. In general, the number of licensed collectors has increased substantially, landings of fish and animal invertebrates peaked in 1994, angelfish dominated the fish landings, live rock dominated the invertebrate landings, and the average landings per trip have remained relatively constant. (67pp.

Uncertainties around the implementation of a clearing-control policy in a unique catchment in Northern Australia: exploring equity issues and balancing competing objectives

Land use change is the most significant driver linked to global species extinctions. In Northern Australia, the landscape is still relatively intact with very low levels of clearing. However, a re-energized political discourse around creating a northern food bowl means that currently intact ecosystems in northern Australia could be under imminent threat from increased land clearing and water extraction. These impacts are likely to be concentrated in a few regions with suitable soils and water supplies. The Daly River Catchment in the Northern Territory is an important catchment for both conservation and development. Land use in the Daly catchment has been subject to clearing guidelines that are largely untested in terms of their eventual implications for the spatial configuration of conservation and development. Given the guidelines are not legislated they might also be removed or revised by subsequent Territory Governments, including the recently-elected one. We examine the uncertainties around the spatial implications of full implementation of the Daly clearing guidelines and their potential effects on equity of opportunity across land tenures and land uses. We also examine how removal of the guidelines could affect conservation in the catchment. We conclude that the guidelines are important in supporting development in the catchment while still achieving conservation goals, and we recommend ways of implementing the guidelines to make best use of available land resources for intensified production