Moral Hazard, Incentive Contracts and Risk: Evidence from Procurement

Deadlines and penalties are widely used to incentivize effort. We model how these incentive contracts affect the work rate and time taken in a procurement setting, characterizing the efficient contract design. Using new micro-level data on Minnesota highway construction contracts that includes day-by-day information on work plans, hours actually worked and delays, we find evidence of moral hazard. As an application, we build an econometric model that endogenizes the work rate, and simulate how different incentive structures affect outcomes and the variance of contractor payments. Accounting for the traffic delays caused by construction, switching to a more efficient design would substantially increase welfare without substantially increasing the risk borne by contractors.

Procurement Contracting with Time Incentives: Theory and Evidence

In public sector procurement, social welfare often depends on the time taken to complete the contract. A leading example is highway construction, where slow completion times inflict a negative externality on commuters. Recently, highway departments have introduced innovative contracting methods based on scoring auctions that give contractors explicit time incentives. We characterize equilibrium bidding and efficient design of these contracts. We then gather an extensive data set of highway repair projects awarded by the California Department of Transportation between 2003 and 2008 that includes both innovative and standard contracts. Comparing similar con- tracts in which the innovative design was and was not used, we show that the welfare gains to commuters from quicker completion substantially exceeded the increase in the winning bid. Having argued that the current policy is effective, we then develop a structural econometric model that endogenizes participation and bidding to examine counterfactual policies. Our estimates suggest that while the current policy raised com- muter surplus relative to the contractor's costs by $359M (6.8$1.52B (29%).

Competition Policy in Small Distant Open Economies: Some Lessons from the Economics Literature

New Zealand is a small open economy that is remote from all major markets. The smallness and remoteness of New Zealand combine to imply that this country has, at least quantitatively, distinctive features for the regulation of economic activity by competition law. The isolation and small size of the economy mean that typically all but exporting firms are small as judged on a world scale, and that domestic markets are small and generally highly concentrated. This paper reviews the economic literature on the implications of an economy’s size and isolation for competition law. The literature suggests that principles underlying competition law do not change for small economies, but that the application of competition law should be different. In small economies, low regulatory and tax barriers to trade dominate the importance of competition law for good economic performance of domestic markets. In these economies, competition law should focus on economic benefit/detriment evaluations of mergers and trade practices rather than rules of thumb of the sort based on measures of market structure and indicators of competition, or those aimed at prohibiting particular practices per se. Producers’ surplus should not be de-emphasised in the calculation of benefits and detriments in small economies; particularly for activities that relate in any way to (potential) export activity. For any economy, particularly in the presence of competition, cooperation enhances economic performance in specific circumstances. In small economies cooperation can be particularly efficient-for example, in achieving scale and thereby export performance-although it may entail interaction among a large fraction of players in an industry. The approach that the literature suggests to the application of competition law in small economies places relatively heavy weight on dynamic efficiency as the criterion for competition law design and enforcement. It is squarely in accord with recommendations in the literature on desirable competition law for the so-called new economy.Small; Isolated; Economy; Antitrust; New Zealand; Producer Surplus: Consumer Surplus; Competition Law; Economic Benefit; Economic Detriment; Rule of Reason

Giving order to image queries

Users of image retrieval systems often find it frustrating that the image they are looking for is not ranked near the top of the results they are presented. This paper presents a computational approach for ranking keyworded images in order of relevance to a given keyword. Our approach uses machine learning to attempt to learn what visual features within an image are most related to the keywords, and then provide ranking based on similarity to a visual aggregate. To evaluate the technique, a Web 2.0 application has been developed to obtain a corpus of user-generated ranking information for a given image collection that can be used to evaluate the performance of the ranking algorithm

Observations of formaldehyde and search for cyanoacetylene in Comet Brorsen-Metcalf (1989o)

The Very Large Array (VLA) was used in September 1989 to search Comet P/Brorsen-Metcalf (1989o) for the 1 sub 11-1 sub 10 transition of formaldehyde (H2CO) at 4,829.659 MHz and for the J equals 1-0, F equals 2-1 rotational transition of cyanoacetylene (HC3N) at 9098.3321 MHz. A new technique was used in reducing the data. Data blocks which were either 3x3 pixels, 5x5 pixels, or 9x9 pixels were examined for a signal from H2CO. Using this approach, different pixel clusters within the field of view can be sampled to optimize the coupling of the synthesized beam to the gas distribution. HC3N is of immediate interest as a cometary molecule because it may be a reservoir of carbon and a source of cometary CN. Our search for HC3N emission at 3.3 cm wavelength demonstrated that for this molecule the VLA can be expected to reach significant levels of sensitivity in many comets

Radar interferometric studies of comets

Our objectives are to use radio interferometry to study composition, velocity distribution, maser excitation, and plasma interactions of cometary gas. Two new cometary chemistry programs were started with radio interferometers: (1) the VLA used to search for HC3N emission from Comet Brorsen-Metcalf at 3.3 cm wavelength; and (2) the BIMA millimeter array used to observe Comet Austin in HCN

Modular Multilevel Converter Based High Voltage DC Protection

This thesis addresses the protection of a high voltage DC (HVDC) system that utilizes the modular multilevel converter (MMC) topology, a voltage sourced converter (VSC), and incorporates two transmission line sections, a cable and an overhead line. Protection for high voltage AC systems is mature in installation experience. On the other hand there are many avenues of research needs for the protection of the more modern technology, HVDC. The avenue of system protection focused upon in this work is the system restart sequence post DC side faults. This restart sequence is simply the sequence of events that occur necessarily in order to restart the HVDC system after a specified fault is already isolated and diminished. This avenue of system protection is focused upon but not exclusively. Fault isolation and suppression are also protection topics noted and discussed. Ultimately a fault section identification protection method is required for restart of the HVDC system when there are two transmission line sections. Specific to the HVDC system design presented there is desire for no communication channel between the converter stations of the system. Additionally, recovery of the system to normal operation is preferably as fast as possible in order to maintain power delivery with minimal disturbance. Solutions to these challenges are investigated and proposed. The first part of this thesis work involves the detailed modeling of the MMC-HVDC system in the PSCAD simulation environment. After providing the validation of the model, both a parameter sensitivity analysis and an in-depth fault case analysis are performed for the overall examination of protection needs of the HVDC design. The fault analysis evaluation brings to light the means for a unique protection coordination method for the system design during post-fault system restart. The protection method ensures that cable faults, assumed to be permanent faults, are not reclosed upon while for any non-permanent faults attempt of reclose is made. The protection coordination method proposed in this work is unique in that it utilizes a signal characteristic to the HVDC system design to implement protection coordination without the use of a communications channel between converter stations

Spatial Drivers of Freshwater Fish Biodiversity, Community Structure, and Diet Composition Across Georgia, USA

The geographic complexity of the Southeastern United States, in particular Georgia, is evident in the diversity of stream habitats present throughout that host unique stream fish communities but is threatened by anthropogenic activity. This spatial complexity can be captured through the ecoregion framework, which delineates areas of distinct habitat. However, this differing habitat character between ecoregions leads to different environmental pressures that may promote species heterogeneity between communities, may create intraspecific niche diversity in widely distributed species, and may complicate the transferability of widely accepted theoretical models of fish ecology between them. I analyzed a long-term fish community dataset, examining abiotic, taxonomic, and functional variation between communities across Georgia to assess the roles of local and regional environmental variables in structuring community composition and the role of ecoregion in mediating these relationships. I found that taxonomic and functional community variation were more affected by region-scale processes than by local variation. Further, although I found that ecoregion was effective in capturing this heterogeneity, biogeographic effects through basin similarity also significantly affects community composition. I assessed individual ecological variation in response to changes in stream size, ecoregion, and season through variations in diet composition in Redbreast Sunfish (Lepomis auritus), a widely distributed generalist feeder. I found that stream size and ecoregion significantly affect prey richness and the relative contribution of terrestrial prey items to their diets. My findings highlight the importance of region-scale processes in shaping local stream fish ecology through the fitness of their individuals and the composition of their communities

Semantic Web Integration of Cultural Heritage Sources

In this paper, we describe research into the use of ontologies to integrate access to cultural heritage and photographic archives. The use of the CIDOC CRM and CRM Core ontologies are described together with the metadata mapping methodology. A system integrating data from four content providers will be demonstrated