It was in 2004 that the first case study was done by on the ongoing Reverse Auction Bidding at Texas A&M University. This long-term study has developed from a single case study, completed by van Vleet, to a series of case studies, now combined with personality testing of all participants. van Vleet developed a Microsoft Access database system and Active Server Pages web based user interface for the study. The first case study involved five participants with no prior experience in Reverse Auction Bidding. A study with five participants is considered competitive in accordance with the standard economic Herfindahl Index. van Vleet, concluded that the results showed a level of co-operation in the bidding game between the nominal competitors. In 2010 John Nichols coined the term "tacit collusion" to identify this apparent behavioural pattern observed in the bidding. A significant element of the studies from 2005 to 2009 has been to investigate the "tacit collusion" behaviour. Tacit collusion is not considered an illegal economic behaviour. In 2006 Seth Gregory encountered significant problems with a study involving ten participants using the Access database, as a result of Access' limitations on the number of connections. Gregory's study was migrated to a Microsoft SQL database that was developed by Wellington (2006) and which overcame the limitations. SQL database systems can generate a significant quantity of data which create a computer science problem, now commonly termed 'Data rich - analysis poor'. This study is the first in a series of studies to undertake a detailed statistical study of the early case studies to provide a set of algorithms for development of SQL queries for automated real-time data analysis of future Reverse Auction Bidding case studies. This study showed that a fifth order polynomial fit the contract time compared to the job number. Analysis of the number of bids per minute for the fifteen minutes of bid time showed a log-polynomial equation which provided a reasonable fit to the data. Two sub-games were postulated to describe the operational aspects of the auction. The first game, termed the - game, is between the players with the objective of maximizing average return and the second game, termed the - game, has the objective of average cost minimization for the purchasers and maximization of revenue for the seller group. In conclusion, Reverse Auction Bidding systems are not bid shopping, but the tenet that the purchaser will reduce costs in this type of system compared to the traditional closed bid system is not confirmed with van Vleet's data and any careful consideration of the results of canny players in the 'game suggests higher than average returns for some bidders. The results show a number of patterns in the data that warrant further study, particularly the characteristics of the canny players in the alpha game suggests higher than average returns for some bidders. The results show a number of patterns in the data that warrant further study, particularly the characteristics of the canny players.

In this paper, we examine the effects of market competition on corporate performance. In the first stage, we use Herfindahl-Hirschman Index to measure the degree of competition and markets are divided into three categories, namely competition, moderate competition and oligopoly. Fama-French is used to examine whether there is abnormal return existing in competition market. Then we use the index constructed by Chen, Kao, Tsao and Wu (2007) to decide the performance of internal governance and use it with competition degree to conduct the regression. This paper finds the following results, 1. the moderate competition market is reducing; 2. the portfolio of firms in competition markets outperforms that in oligopoly; 3. market competition has positive effect on ROA, ROE, EPS and Tobin¡¦s Q; 4. market competition and corporate governance are complementary.

Den 1 juli 2010 implementerades PSI-lagen i Sverige, syftet var att främja konkurrens och tillväxt i informationsförädlarbranschen. En bransch som beräknas ha en stor tillväxtpotential. Branschen saknar idag en egen klassifikation, vilket medför att branschens utveckling är svår att mäta. Denna studie avser att dels skapa en definition för informationsförädlarbranschen, och ta reda på vilka företagen i branschen är. Sedan kommer konkurrens och tillväxt i informationsförädlarbranschen att mätas för att undersöka om PSI-lagen haft någon inverkan på branschens utveckling. Resultatet visar att branschen består av 130 företag, år 2013, och att tillväxten och konkurrensen har förändrats sedan PSI-lagen implementerats.

This study seeks to determine if media ownership diversity remains at levels widely considered to be competitive and acceptable, despite consolidation within the media industry. The research augments the many studies analyzing programming diversity within the U. S. media industry. Rather than analyzing programming content, this study addresses ownership diversity by examining the diversity of media ownership within the context U. S. model, considered to be more of a decentralized, market-driven media industry when compared to other countries such as the United Kingdom or Canada. To measure diversity, the HerfindahlHirschman Index (HHI)—a measure of economic diversity widely used by economists as well as government regulatory agencies—is used. Suggestions are presented for the future of media and regulation to insure a competitive, diverse, and healthy media industry.

Submitted by Rodolfo Rodriguez (rodolfo.rodriguez@itau-unibanco.com.br) on 2010-06-02T12:00:51Z No. of bitstreams: 1 Dissertacao_Rodolfo_Rodriguez.pdf: 513830 bytes, checksum: 559d56f7d39065af19e2fb8f14ce69d4 (MD5) / Approved for entry into archive by Daniella Santos(daniella.santos@fgv.br) on 2010-06-02T12:14:42Z (GMT) No. of bitstreams: 1 Dissertacao_Rodolfo_Rodriguez.pdf: 513830 bytes, checksum: 559d56f7d39065af19e2fb8f14ce69d4 (MD5) / Made available in DSpace on 2010-06-02T14:06:40Z (GMT). No. of bitstreams: 1 Dissertacao_Rodolfo_Rodriguez.pdf: 513830 bytes, checksum: 559d56f7d39065af19e2fb8f14ce69d4 (MD5) Previous issue date: 2007-07-16 / Insurance markets under supervision of SUSEP have shown decrease in number of companies and increase in Herfindahl Hirschman Index. This potential issue is undermined by Gini Index and other market Power tests that indicate that prices were not affected accordingly. International experience shows concentration to be higher in life insurance than non life insurance. This fact has impact in prices, which are higher in life insurance market, and indicates relevant differences between life and non life insurance markets. / Os mercados de seguros regulados pela SUSEP apresentaram queda no número de empresas e elevação no índice de concentração de Herfindahl Hirschman. O que parece um quadro preocupante no âmbito da regulação é atenuado pela diminuição do índice de Gini e outros testes de poder de mercado que não indicam que esta queda no número de empresas tenha tido impacto sobre o nível de preços. Assim como esperado a partir da evidência internacional, a concentração é maior nos mercados de seguros de vida do que nos não-vida. Este fato tem reflexo nos preços, que apresentam patamares mais altos nos seguros de vida, indicando diferença mais substancial entre mercados.

This master thesis is focused on the market concentration in six sectors of public procurements in the Czech Republic, and the relationship between level of market concentration, profitability of the companies, final price and number of bids. The analyzed procurements refer to food industry, electricity, postal and telecommunications services, solar energy, IT and automotive sector from period of 2007-2010. Concentration ratio, Herfindahl-Hirschman index and Gini coefficient were used to quantify market concentration. The first four of above mentioned public procurement markets seem to be highly concentrated according to these indicators; the remaining two cases are unconcentrated or moderately concentrated. Correlation analysis was used for each sector. The analyzed variables were: market shares of the companies, their profitability, average number of bids and average proportion of the final and expected price in tenders which the company won. Further, the relationship between market concentration indicators and average variables for the relevant sectors was assessed.

After the financial crisis, several comparison websites have emerged for private lenders to enable comparison on mortgage terms. The idea behind the comparison pages is that they should be used by the private borrower. On June 1, 2015, a new directive emerged from the Swedish Financial Supervisory Authority to the credit institutes that instead of the list interest, the average interest rate that the lenders offer their customers should be the one published, in order to further increase the transparency of the price. The purpose of this study is to investigate whether competition in the mortgage market has improved after the introduction of the comparison websites and the effects of the increased price transparency. In order to investigate the competition on the mortgage market, the theory of market forms and the Herfindahl-Hirschman Index has been applied. The result of the study shows that the concentration of competition has increased over time. This study also shows that the comparison pages have contributed to increased price transparency that has contributed to consumers information about the market. This study is limited to the Swedish mortgage market. / Efter finanskrisen har flertalet jämförelsesidor uppkommit för att möjliggöra jämförelser av räntor och villkor på bolån. Jämförelsesidor ska förenkla processen att jämföra de olika långivarna. Den 1 juni 2015 kom ett nytt direktiv från finansinspektionen till långivarna att istället för listräntan ska den genomsnittliga räntan som långivarna ger sina kunder vara den som publiceras, för att öka pristransparensen ytterligare. Denna studies syfte är att undersöka hur konkurrensen på bolånemarknaden har förändrats efter jämförelsesidornas tillkomst med HHI-index och konkurrensteori. Teori om marknadsformer och Herfindahl-Hirschman Index att tillämpas för att undersöka konkurrensen. Resultatet av studien visar att koncentrationen av konkurrensen har ökat över tid. Denna studie visar även att jämförelsesidorna har bidragit med ökad pristransparens som har bidragit till konsumenternas information om marknaden. Studien är avgränsad till den svenska bolånemarknaden.

Syftet med studien är att analysera förändringen i de svenska partiernas politiska program genom att tillämpa Public Choice skolans modeller. Med hjälp av medianväljarteoremet och Hotellingmodellen analyseras om modellerna är tillräckligt beskrivande för Sveriges partiförflyttningar. Vidare beräknas Herfindahl-Hirschman index för graden av maktkoncentration på den politiska ”marknaden”. Herfindahl-Hirschman indexet visar att koncentrationen på den politiska marknad blivit lägre över tid, viket indikerar på att konkurrensen mellan partierna blivit allt högre under perioden 1973-2014. För att analysera om det går att förklara förändringar i partiernas politik under perioden 1973-2014 tillämpas medianväljarteoremet. En diskussion kring testning av modellen görs samt en illustration hur medianväljarteoremet skulle kunna se ut för Sveriges partier. För att analysera om en endimensionell skala är beskrivande för de svenska partiernas förflyttningar har Hotellingmodellen tillämpats. Genom att illustrera dessa två modeller på Sveriges partier undersöks om modellerna ger en tillfredställande beskrivningar av förändringen i de svenska partiernas politiska program. Analysen ger vid handen att att Medianväljarmodellen inte förklarar förändringarna i partiernas politik på ett tillräckligt utförligt sätt. Hotellingmodellen kan bättre förklar både de svenska partiernas förflyttningar på vänster-högerskalan samt förändringar i partiernas politik. Utöver de nämnda modellerna konstateras att den enskilda faktor som är mest betydelsefull för hur partierna ändrat sina politiska program är partiernas beroende av väljarnas åsikter. / The aim of the study is to analyze changes in the Swedish political parties programs by applying the Public Choice approach. With help from the median voter theorem and the Harold Hotelling model, the paper analyzes if these models are sufficiently descriptive of Swedens political parties movements. A Herfindahl-Hirschman index is constructed which shows changes in concentration of political power over time. The Herfindahl-Hirschman index shows that the degree of concentration in the Swedish political “market” has become lower over time, which indicates that the party competition has increased during the period 1973-2014. In order to analyze whether it is possible to explain changes in the parties’ policies during the period 1973-2014 the median voter theorem is applied. A discussion about how this model can be tested is done as well as an illustration of how the median voter theorem could look like for the parties in Sweden. To analyze whether a one-dimensional scale is descriptive of the movements of the Swedish parties, the Harold Hotelling model is also applied. By illustrating these two models on Swedens parties, the paper investigates whether these models provide a satisfactory descriptions of the change in the Swedish parties political programs. The analysis concludes that the median voter theorem does not explain the changes in the parties politics in a sufficiently detailed manner. It is revealed that the Harold Hotelling model provides a better description for both the Swedish parties movements at the left-right scale and for the changes in the parties politics. In addition to the models mentioned the factor that that is most important for how the parties changed their political programs is the parties’ dependence of the voters opinions.

Thesis (PhD)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: This dissertation examines the measurement of business concentration by the Herfindahl- Hirschman Index (HHI). In the course of the examination, a modification to this method of measurement of business concentration is proposed, in terms of which the accuracy of the conventional depiction of the HHI can be enhanced by a formulation involving the Gini index. Computational advantages in the use of this new method are identified, which reveal the Ginibased HHI to be an effective substitute for its regular counterpart. It is found that theoretically and in practice, the proposed new method has strengths that favour its usage. The practical advantages of employing this method are considered with a view to encouraging the measurement of business concentration using the Gini-based index of the HHI. / AFRIKAANSE OPSOMMING: Hierdie verhandeling ondersoek die meting van sakekonsentrasie deur middel van die Herfindahl- Hirschman-indeks (HHI). ‘n Wysiging aan hierdie metode word voorgestel, deur middel waarvan die akkuraatheid van die konvensionele voorstelling van die HHI verhoog word, deur ‘n formulering wat die Gini-indeks betrek. Die berekeningsvoordele van hierdie nuwe metode word geïdentifiseer en dit word aangetoon dat die Gini-gebaseerde HHI ’n doeltreffende plaasvervanger vir sy meer bekende teenvoeter is. Daar word bevind dat die voorgestelde nuwe metode teoretiese en praktiese sterkpunte het wat die gebruik daarvan ondersteun. Die praktiese voordele van die voorgestelde metode word oorweeg met die oog op die aanmoediging van die gebruik van die Gini-gebaseerde HHI-indeks as maatstaf van sakekonsentrasie.

Cílem diplomové práce je analýza vztahu tržní koncentrace a efektivnosti odvětví. Přestože potvrzený vztah může být významný pro mnoho subjektů v ekonomice, doposud provedené empirické studie nedávají jasnou odpověď na otázku, zda jsou firmy fungující v odvětvích s vyšší tržní koncentrací efektivnější či nikoli. K analýze jsou použita data Českého statistického úřadu, která jsou tříděna a agregována dle odvětvové klasifikace ekonomických činností. Datová základna poskytuje údaje za roky 1998 až 2006 a jedná se výhradně o zpracovatelský průmysl České republiky. Metodou ověřování vztahu koncentrace ? efektivnost odvětví je regresní a korelační analýza.