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Reverse Auction Bidding - Bid Arrivals AnalysisYuan, Shu 16 December 2013 (has links)
Reverse Auction Bidding (RAB) is a recently developed procurement method that can be used by the construction industry. The technique is different from a traditional auction system, since RAB system uses a bidding activity method that is completed anonymously by pre-qualified bidders during a fixed auction time. The basic premise for the auction is that the current best auction price is available for viewing during the whole auction process by both bidders and owner. The apparent incentive is for noncompetitive bidders to lower the price. There are however controlling factor beyond the reach of owners, such as market demand, lending restrictions, stakeholder expectations and risk tolerance levels, that impact on price levels. However, owners continue to attempt to drive down prices using this technique.
A study into the mechanics of RAB was launched at Texas A&M University in 2004. This ongoing study of RAB continues to this time with eighteen case studies. This nineteenth study looks at the time series bid data from some of the prior work. Nine case studies were selected from the previous case studies. These nine studies provided untainted data with 6674 RAB bid arrivals by prior investigator actions. This study concerns the statistical process of bid arrivals with time.
The hypothesis to be tested is that the RAB bid arrivals timing can be modeled with a statistical process. The analysis reviewed the fit for several types of distribution, including Gaussian and Poissionian. The best fit was modeled by non-homogeneous Poisson process (NHPP). The first conclusion from the analysis is that RAB bid arrivals follows a Poisson process, termed non-homogeneous Poisson process (NHPP). The second conclusion is that the controlling Poissionian process has a square root factor. The NHPP model for RAB provides a tool for future studies of RAB in real time. Future work is suggested on the inter-time periods for the bidding.
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Traffic management alternatives for business improvement districtsHarris, Darren Samuel 27 August 2014 (has links)
When a vehicle enters an intersection with insufficient space to exit on the opposite side the
result is often the obstruction of pedestrians and other vehicles, this phenomenon is usually referred to as "blocking the box." The purpose of this study was to determine different characteristics of blocking that might be considered in determining the installment of a "Don't Block the Box" (DBTB) campaign. This study identified potentially problematic intersections in Atlanta, Georgia and collected information, such as the number of vehicles that block the intersection (box junction), the amount of green time with blocking, and the percentages in which approaches were blocked.
Based on the results it was found the characteristics of the number of blockers, percentage of green time with blocking, and the percentage of lost capacity are excellent indicators for a possible DBTB campaign. Organizations interested in potentially starting a DBTB should consider these characteristics part of the determination of suitability of DBTB for an intersection. Within this study is was found that the intersections of Peachtree Road & Highland Drive, Peachtree Road & Stratford Road, Peachtree Road & Lenox Mall Entrance, and 10th Street & Williams Street showed to be potential candidates for a DBTB campaign in Atlanta, Georgia. During the study period these intersections had high percentages of lost capacity, high number of blocks, and high percentages of green time with blocking.
In conjunction with the DBTB data analysis a "DBTB survey" was developed. The objective of this survey was to help gain a better understanding of the current trends in DBTB campaigns around the United States. The "DBTB Survey" received 75 responses from 415 organizations around the nation, a 18.1% response rate. Six (60%) of the ten participants that currently have a DBTB campaign found a sufficient level of improvement in traffic operations and 46 of the total respondents (60%) proclaimed that if DBTB campaigns were shown to be an economical alternative for traffic management they would consider starting one to help congestion and safety.
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How Insiders and Informational Events Affect Bid-Ask Spreads: A Simulation-Based ApproachRunde, Andrew G 01 January 2014 (has links)
This paper will examine the effects of inside information on bid-ask spreads when the probability of insider trading and the likelihood of an informational event occurring varies using a theoretical, simulation-based approach. The results show that bid-ask spreads narrow as the number of time periods increase, regardless of probability of insider trading or the likelihood of an informational event occurring. For a high, given likelihood of an informational event occurring, the highest average spreads were found for lower probabilities of insider trading as time increased. For a high, given probability of insider trading, the highest average spreads were found for lower likelihoods of an informational event occurring as time increased. The variances increased along with the probability of insider trading as well as with the likelihood of an informational event occurring. The maximum average spread settled near 0.25, typically found for a probability of insider trading of 1 and a likelihood of an information event occurring of 0.5. The results verify previous research done by Glosten and Milgrom (1985), Easley, Hvidkjaer and O’Hara (2002) and Potterton (2011). The results also may reconcile the differences between the findings of Easley, Hvidkjaer and O’Hara (2002) and Potterton (2011).
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O projeto e a encomenda pública da arquitetura : lex versus publica architecturaeSilva, Tiago Holzmann da January 2018 (has links)
A falta de qualidade das obras públicas no Brasil povoa os noticiários diários. Os exemplos são abundantes, atribuídos a contratos mal elaborados, falhas graves nos projetos ou mesmo à ausência desses, licitações frustradas, obras interrompidas e superfaturadas, desvios de recursos e corrupção. Tentar compreender melhor essa situação é a motivação desta dissertação, que discorre sobre a contratação pública de projetos de edificações e, para isso, estuda o projeto e sua encomenda. A licitação é um procedimento obrigatório para a celebração de qualquer contrato público. Entre outros requisitos, a lei de licitações exige que a proposta seja a “mais vantajosa” para a administração, algo que tem levado à adoção indiscriminada do critério do “menor preço”, sendo incoerente com a doutrina jurídica e contrariando as pesquisas científicas, que consideram o projeto relevante para a qualidade final da obra. O problema de pesquisa questiona exatamente por que a Administração Pública tem contratado por menor preço um serviço que deveria ser contratado por critérios técnicos e de qualidade? O objetivo da dissertação é propor uma explicação para essa situação a partir de revisão bibliográfica, análise da legislação, realização de pesquisa documental com editais de licitação, aplicação de questionários de opinião com arquitetos e outros atores, além de entrevista direta com o autor da lei de licitações. Finalmente, o trabalho comprova a relevância do projeto, mas também desvenda sua irrelevância identificando que o menor preço não é o único problema e, mesmo que “todos” afirmem ser contra o menor preço, o povo segue pagando caro por projetos baratos. / The qualityless of public works in Brazil is currently in the daily news. Examples of it are plentiful, attributed to poorly drafted contracts, serious failures or even absence of projects, frustrated bids, discontinued and overpriced works, waste of resources and corruption. The motivation of this dissertation is trying to better understand this situation, which focuses on the public contracting of building projects and, for this, studies the project itself and its order. Bidding is a mandatory procedure for obtaining any public contract. Among other requirements, the bidding law requires that the proposal be the "most advantageous" for the administration, which ledded to the indiscriminate adoption of the "lowest price" criteria, incoerent with the juridical doctrine and opposite to scientific research, which consider the project relevant to the final quality of the building work. The research problem questions why the Public Administration has contracted for a lower price a service that should be contracted by technical and quality criteria? The objective of the dissertation is to propose an explanation for this situation from a bibliographical review, an analysis of the legislation, a documental research on bid’s documents, an opinion questionaries applying to architects and other actors, as well as direct interview with the author of the bidding law. Finally, the research proves the relevance of the project, but also reveals its irrelevance by identifying that the lowest price is not the only problem, and even if "everyone" claims to be against the lowest price, people continue to pay expensive for cheap projects.
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Veřejné zakázky a bid riggingKrejčová, Hana January 2016 (has links)
The Diploma thesis deals with the public procurement issue and the bid rigging. The first part of this thesis is focused theoretically on related legislation of public procurement in the Czech Republic. Herein are in this thesis defined public pro-curements and their types, role of contracting authority and award procedure. The further chapter is devoted to the bid rigging and to its theoretical background. The second part of thesis analyses decisions of the case law of bid rigging, influence of the bid rigging. Furthermore, there are suggested the possible results of detection and prevention of bid rigging.
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O projeto e a encomenda pública da arquitetura : lex versus publica architecturaeSilva, Tiago Holzmann da January 2018 (has links)
A falta de qualidade das obras públicas no Brasil povoa os noticiários diários. Os exemplos são abundantes, atribuídos a contratos mal elaborados, falhas graves nos projetos ou mesmo à ausência desses, licitações frustradas, obras interrompidas e superfaturadas, desvios de recursos e corrupção. Tentar compreender melhor essa situação é a motivação desta dissertação, que discorre sobre a contratação pública de projetos de edificações e, para isso, estuda o projeto e sua encomenda. A licitação é um procedimento obrigatório para a celebração de qualquer contrato público. Entre outros requisitos, a lei de licitações exige que a proposta seja a “mais vantajosa” para a administração, algo que tem levado à adoção indiscriminada do critério do “menor preço”, sendo incoerente com a doutrina jurídica e contrariando as pesquisas científicas, que consideram o projeto relevante para a qualidade final da obra. O problema de pesquisa questiona exatamente por que a Administração Pública tem contratado por menor preço um serviço que deveria ser contratado por critérios técnicos e de qualidade? O objetivo da dissertação é propor uma explicação para essa situação a partir de revisão bibliográfica, análise da legislação, realização de pesquisa documental com editais de licitação, aplicação de questionários de opinião com arquitetos e outros atores, além de entrevista direta com o autor da lei de licitações. Finalmente, o trabalho comprova a relevância do projeto, mas também desvenda sua irrelevância identificando que o menor preço não é o único problema e, mesmo que “todos” afirmem ser contra o menor preço, o povo segue pagando caro por projetos baratos. / The qualityless of public works in Brazil is currently in the daily news. Examples of it are plentiful, attributed to poorly drafted contracts, serious failures or even absence of projects, frustrated bids, discontinued and overpriced works, waste of resources and corruption. The motivation of this dissertation is trying to better understand this situation, which focuses on the public contracting of building projects and, for this, studies the project itself and its order. Bidding is a mandatory procedure for obtaining any public contract. Among other requirements, the bidding law requires that the proposal be the "most advantageous" for the administration, which ledded to the indiscriminate adoption of the "lowest price" criteria, incoerent with the juridical doctrine and opposite to scientific research, which consider the project relevant to the final quality of the building work. The research problem questions why the Public Administration has contracted for a lower price a service that should be contracted by technical and quality criteria? The objective of the dissertation is to propose an explanation for this situation from a bibliographical review, an analysis of the legislation, a documental research on bid’s documents, an opinion questionaries applying to architects and other actors, as well as direct interview with the author of the bidding law. Finally, the research proves the relevance of the project, but also reveals its irrelevance by identifying that the lowest price is not the only problem, and even if "everyone" claims to be against the lowest price, people continue to pay expensive for cheap projects.
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Upgrade the Saudi Arabian Procurement System Delivery MethodJanuary 2015 (has links)
abstract: Saudi Arabia has been having many issues with large construction projects such as delays, low performance and high cost. Some studies show that around 70% of the public projects in Saudi Arabia are delayed. These issues have resulted from many factors. One of the factors believed to be delaying projects is the Saudi procurement system. The Saudi procurement system only selects contracts based on the lowest bid price offered. However, the Saudi procurement system has been found to not only produce delayed low quality projects, but also has resulted in higher costs.
This paper shows how to modify the Saudi procurement system by implementing a clarification phase, which is the most important phase in the Performance Information Procurement System (PIPS). The clarification phase requires the bid’s winning contractor to submit a project scope, a project schedule, to identify risks that not their responsibility, performance measurements and a milestone schedule. The PIPS system has been one of the most successful systems around the world and has shown a 98% success rate in six different countries with risks and cost reductions up to 30%.
This research conducted a survey of 157 engineers, 33 consultants, 9 owners, 5 vendors, 13 academics, and 28 architects to develop the public procurement system in Saudi Arabia. The participants work in government sectors with an interest in the Saudi Arabian procurement system. 80.61 % of participants believe that the traditional Saudi procurement system consistently selects poor performing contractors. Moreover, 95.97% of participants think that the selection of contractors based only on the lowest price criterion affects projects negatively. Also, 96.20% of participants in the survey feel that there needs to be a change in the traditional Saudi Arabian procurement system. 88.7% of participants agree to require the contractor to identify risks, and 96.03 % of participants agree that the contractors must have a plan. Moreover, 95.45% of participants agree to require a contractor review the scope of a project and verify that it is correct. Finally, 82.18% of participants agree to require a contractor to resolve all owner concerns before signing a contract to improve construction projects performance. The paper shows the need to change the Saudi procurement system and a solution to this growing problem. / Dissertation/Thesis / Masters Thesis Construction 2015
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Evaluación de una prueba estadística para detectar endogeneidad en modelos Bid de uso de sueloSoto Vaquero, José Ricardo January 2019 (has links)
Memoria para optar al título de Ingeniero Civil / Los modelos de uso de suelo permiten analizar la interacción entre los sistemas de transporte y el mercado inmobiliario. Esto los vuelve una herramienta de gran importancia para la toma de decisiones que concluye en proyectos como una línea de metro, un edificio comercial o un nuevo plano regulador. Considerando el alcance y consecuencias que tienen esta clase de proyectos en la sociedad, resulta fundamental que los modelos propuestos sean consistentes y permitan realizar pronósticos que reflejen la realidad en escenarios futuros.
Los modelos de uso de suelo actuales son desarrollados bajo un enfoque Bid de máxima postura aleatoria, que podrían sufrir de endogeneidad debido, entre otras cosas, a la omisión de atributos, difíciles de medir pero muy influyentes en lo observado. La detección y correc- ción de endogeneidad ha sido estudiada ampliamente en el contexto de elecciones discretas (Louviere et al., 2005; Guevara, 2015), pero no en el caso particular del modelo Bid.
Se han desarrollado múltiples metodologías para estimar modelos Bid (Ellickson, 1981; Lerman y Kern, 1983) que varían en términos de eficiencia. En consideración de lo anterior, esta memoria propone el desarrollo de una prueba de hipótesis basada en la prueba de especificación de Hausman y McFadden (1984) que logre detectar endogeneidad en modelos Bid. La principal ventaja que presenta el test propuesto frente a otras opciones es el no requerir de supuestos adicionales ni del uso de variables instrumentales para ser aplicado.
Para estudiar el test propuesto se desarrolla un experimento de Monte Carlo donde se evalúan los indicadores de size distortion y poder empírico del test, los que son contrastados con el método de funciones de control. Este último se propone como alternativa pese al inconveniente de exigir el uso de variables instrumentales. El experimento simula una ciudad monocéntrica compuesta por hogares de dos estratos socioeconómicos donde se realiza un remate de viviendas a partir de un conjunto de atributos dado, logrando un equilibrio de mercado controlando la distribución de hogares por estrato y suponiendo un precio pagado igual a la máxima postura observada. Luego, se procede a estimar el modelo omitiendo un atributo de la simulación, que deriva en una fuente de endogeneidad que permite evaluar el test.
La simulación concluye que la prueba desarrollada es capaz de detectar endogeneidad bajo ciertas condiciones. No obstante, existen casos donde el test puede fallar. En particular, cuando la valoración del atributo omitido es diferente para cada estrato se observan caídas en el poder empírico del test. Por otra parte, la comparación realizada con funciones de control muestra que este último posee mayor poder, mas el uso de variables instrumentales sigue representando un inconveniente que el test propuesto logra subsanar. / Fondecyt No. 1150590
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Models and Algorithms for Procurement Combinatorial AuctionsMansouri, Bahareh 11 1900 (has links)
A key problem in designing marketplaces is how to efficiently allocate a collection of goods among multiple people. Auctions have emerged as a powerful tool with the promise to increase market efficiency by allocating goods to those who value them the most. Nevertheless, traditional auctions are unable to handle real-world market complexities. Over the past decade, there has been a trend towards allowing for package bids and other types of multidimensional bidding techniques that enable suppliers to take advantage of their unique abilities and put forth their best offers. In particular the application of iterative combinatorial auctions in procurement saves negotiation costs and time. Conceptually these auctions show a potential for improving the overall market efficiency. However, in practice they host several new challenges and difficulties.
One challenge facing the auctioneer in an iterative combinatorial auction environment is to quickly find an acceptable solution for each round of the auction. Bidders require time to precisely evaluate, price, and communicate different possible combinations based on their current information of item prices. The auctioneer requires time to solve the underlying mathematical problem formulation based on the bids received, report back the feedback information and initiate a new round of the auction.
In Chapter 3, we propose a Lagrangian-based heuristic to solve the auctioneer's winner determination problem. After generating the Lagrange multipliers from the solution of a linear relaxation, the heuristic applies several procedures to fix any potentially infeasible optimal Lagrange solutions. In addition to providing an efficient way of solving the winner determination problem, as compared with the leading commercial solver CPLEX, our approach provides Lagrange multipliers. The latter are used as proxies for prices in the auction feedback mechanism.
In Chapter 4 we develop a model for the bidders pricing problem, an issue that has received much less attention in the literature. Using the auctioneer feedback, that includes the Lagrange multipliers, the pricing model maximizes the bidders' profit while at the same time keeping their bids competitive. We derive several optimality results for the underlying optimization problem. Interestingly, we analytically show that the auction converges to a point where no bidder is able to submit a bid that yields strictly better profit for him and is not less competitive than his previous bids submitted. We experimentally observe that this approach converges in an early stage. We also find that this iterative auction allows the bidders to improve their profit while providing lower and competitive prices to the auctioneer.
In Chapter 5, we introduce a flexible auction model that allows for partial bids. Rather than the regular all-or-nothing indivisible package bids, divisible bids provide flexibility for the auctioneer with the possibility to accept parts of the bids and yet allow the suppliers to capture synergies among the items and provide quantity discounts. We show numerically that this approach improves the overall efficiency of the auction by increasing the suppliers' profit while decreasing the auctioneer's total price of procurement. In addition, we find that computationally the flexible auction outperforms the regular auction. / Thesis / Doctor of Philosophy (PhD)
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Changing Traditions: Examining the Factors That Determine the Probability of Bidding to Host the Olympic Games Over TimeDickens, Jessie R 01 January 2018 (has links)
In September 2017, the International Olympic Committee (IOC) announced that, for the first time in its history, it would award the hosting of two different Olympic Games at the same time, giving the 2024 and 2028 Summer Olympic Games to Paris and Los Angeles respectively. As a result, the question is raised as to why the IOC broke tradition in its host city selection process. The break of tradition is presumably due to a lack of candidates to host the 2028 Summer Olympics. With prior host cities reporting astronomical costs and high debt balances associated with hosting, many cities have retracted their bids or have refused to submit candidature bids altogether. The Olympics are one of the largest, most economically impactful mega-events in modern culture. While hosting does provide a nation with the opportunity to show off its infrastructure and culture before millions of people worldwide, the costs to host the event have steadily risen as the Olympics have become a larger and larger spectacle. This study uses a logistic regression model to determine the relative factors that determine a city's willingness to bid and uses the results to draw conclusions as to why the willingness to host has fluctuated across time. The results show a definite change in the probabilities of a potential city bidding to host the Olympic Games across time and also provide insight into the factors that determine these changes in probabilities. By determining these conclusions, this study hopes to provide insight into ways that hosting the Olympics can become accessible to all prospective host cities so that there is increased competition in the host city selection process.
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