[pt] Os modelos de Black & Scholes e binomial para avaliação de opções financeiras dão como resultado prêmios cujo valor aumenta proporcionalmente ao aumento da incerteza do retorno dos ativos subjacentes às opções, medida pelo desvio-padrão. Também na avaliação de empresas, a teoria das opções financeiras pode ser estendida para avaliar as mesmas como opções reais. Este método é adequado quando se analisam ativos de empresas sujeitos a fortes incertezas, situação na qual a flexibilidade das opções adiciona valor considerável aos ativos físicos. Seguindo esta ótica, a pesquisa analisou uma linha aérea internacional de uma empresa de transporte aéreo regular de passageiros. A análise é adequada na medida em que a indústria do transporte aéreo, atualmente em crise, está sujeita a fortes incertezas de receita de passageiros e também de custos como o de combustível. Pela análise por opções reais, a pesquisa demonstrou que a flexibilidade existente acerca das opções de aumentar, reduzir freqüências nos vôos ou até mesmo abandonar as operações, aliada às incertezas de mercado, adiciona valor considerável aos ativos de uma empresa aérea. Assim, avaliar as mesmas apenas baseando-se no método ortodoxo do Valor Presente Líquido num cenário de crise como o atual, constitui-se numa análise incompleta. A pesquisa utilizou uma modelagem discreta no tempo e estado, com a combinação das incertezas de receita e combustível evoluindo segundo uma árvore quadrinomial. / [en] The Black & Scholes and the binomial models for financial options valuation give, as a result, premiums whose value increases proportionally to the increase of the degree of uncertainty about the return of the underlying assets, as measured by the standard deviation. When companies are valuated, financial options theory can be extended to valuate them as real options. This method is adequate when analysing company assets subjected to great uncertainty, in which the options flexibility adds considerable value to the physical assets. In this context, this research shows the analysis of an international airline of a regular passenger air transport company. The analysis is adequate as long as the air transport industry, nowadays in crisis, is subjected to strong uncertainties like passenger revenue and fuel costs. Through the real options analysis, the research showed that the flexibility given by the options of increasing or decreasing flights frequencies, and even of abandoning operations, together with the Market uncertainties, adds considerable value to the assets of an air carrier. In this sense, valuating them only according to the orthodox method of the Net Present Value in a scenario of crisis as nowadays, is an incomplete analysis. The study was based on a discrete time and discrete state model, combining the evolution of revenue and fuel cost uncertainties according to a quadrinomial decision tree.

No description available.

[pt] A globalização e a era da informação impõem novos e complexos desafios para as empresas. A indústria aeronáutica global passa por um período de acirramento da concorrência e uma tendência à concentração. Nesse ambiente, inovar é fundamental. Para atender às exigências crescentes dos clientes, as organizações precisam buscar vantagem competitiva por meio de alianças estratégicas voltadas à inovação, que é apontada como alternativa para melhorar o seu desempenho ou, até mesmo, assegurar a sua sobrevivência. O objetivo final desta dissertação consiste em, por meio de um estudo de caso e com o auxílio do ferramental Strategic Network Analysis - Innovation Framework (SNA-IF) (MACEDO-SOARES, 2014), analisar a estratégia competitiva da Embraer, com ênfase na sua adequação dinâmica, e levando-se em consideração as implicações estratégicas do seu portfólio/rede de alianças e a sua orientação para a inovação. Líder na fabricação de jatos comerciais regionais e maior exportadora de bens de alto valor agregado do Brasil, a empresa é uma integradora de sistemas, que projeta aeronaves, e realiza, dentre outras, atividades relacionadas à montagem, integração de sistemas, comercialização e suporte técnico. As alianças estratégicas da Embraer têm contribuído para o cumprimento de sua missão, fornecendo, assim, bens e serviços de elevado padrão tecnológico e qualitativo na indústria aeronáutica, com preços competitivos, de forma a assegurar a satisfação dos clientes. Têm, assim, uma adequação dinâmica à sua estratégia competitiva de diferenciação por inovação. / [en] Globalization and the information age impose new and complex challenges for business. The global aviation industry is experiencing a period of increased competition and a tendency towards concentration. In this environment, innovation is fundamental. To meet growing customer demands, organizations need to seek competitive advantage through strategic alliances geared to innovation, which is singled out as an alternative to improving their performance or even ensuring their survival. The final objective of this dissertation is to analyze the competitive strategy of Embraer, with emphasis on its dynamic fit, by means of a case study and with the help of the tool Strategic Network Analysis - Innovation Framework (SNA-IF), taking into consideration the strategic implications of its portfolio / network of alliances and its orientation towards innovation. A leader in the production of regional commercial jets and the largest exporter of high value-added goods in Brazil, the company is a system integrator, which designs aircraft, and performs, among others, activities related to assembly, systems integration, marketing and technical support. The strategic alliances of Embraer have contributed to the fulfillment of its mission, providing, therefore, goods and services of high technological and qualitative standard in the aeronautical industry, with competitive prices, in order to assure customer satisfaction. They have, a dynamic fit to the firm s competitive strategy of differentiation by innovation (MACEDO-SOARES, 2014).

This study attempted to establish the travel behaviours and choice criteria of the South African domestic air passenger and how they differed between low-cost carriers (LCCs) and full-service carriers (FSCs). The study was quantitative and used structured questionnaires to collect data via personal interviews. Descriptive and inferential techniques were used to analyse the data, including a binomial logistic regression to identify predictors of model choice. Analysis This study attempted to establish the travel behaviours and choice criteria of the South African domestic air passenger and how they differed between low-cost carriers (LCCs) and full-service carriers (FSCs). The study was quantitative and used structured questionnaires to collect data via personal interviews. Descriptive and inferential techniques were used to analyse the data, including a binomial logistic regression to identify predictors of model choice. Analysis showed that passengers had a limited understanding of the functioning of the models. This results in consumer perceptions and expectations being discordant with the true differences. In distinguishing between models, LCC passengers rate LCCs more favourably than FSC passengers, but both rate FSCs higher than LCCs. This shows the need of consumers to have the features and services of the FSCs. Amongst the key findings was the absolute importance of price to the passengers on both models when purchasing the ticket. The analysis showed that LCC passengers are highly price sensitive and show loyalty to the lowest price (not airline model). It was apparent that frequent flyer programmes (FFP), or linkages to 3rd party loyalty programmes, for LCCs need to be reconsidered. Younger LCC passengers especially, indicated a need for a simple FFP to receive some form of ‘reward’, as well as benefits traditionally only offered by FSCs. FSC passengers show a greater degree of loyalty and less fare sensitivity. This provides the FSCs with a degree of fare flexibility and the opportunity to move their loyal, less price-sensitive consumers up the price curve to maximise revenue. It was shown that, in distinguishing themselves from FSCs, it is important that LCCs are perceived as being more affordable than FSCs and are offering a value-for-money service. In essence, LCCs have to defend their positioning by (i) ensuring that their fares are not perceived to be as high as a FSCs and (ii) watching that the FSC fares are not declining to a level where FSCs are perceived as being as cheap as a LCC. For LCCs, brand building strategies around issues other than fare need to be devised, with attention paid to identifying determinant factors. / Business Management / D. Com (Business Management)

The US airline industry is going through a period of consolidation through mergers between leading airlines. A number of recent mergers have been approved by the Antitrust Division of the Department of Justice (DOJ) based on the presence of Southwest Airlines in merger-affected markets. In doing so, the DOJ makes a key assumption that Southwest is unresponsive to the reduced competition when its competitors merge. We find that Southwest raised fares more in markets where Delta/Northwest and US/America-West used to operate jointly between 2005-2010. However, Southwest's fares either decreased or rose by less if facing direct or adjacent competition from a low-cost carrier (LCC). Furthermore, Southwest is now merging with AirTran Airways, its biggest LCC competitor. This implies that the DOJ should not rely on Southwest Airlines as a post-merger deterrent to fare increases. / Graduation date: 2012

Abstracts in English and Zulu / Airline choice is of interest to both airline product development and marketing personnel and academics. While most of the studies airline choice/service quality only identify airlines service attributes essential to customers, this study employed personal values to extend and provide the reasons why airline service attributes are not or essential to passengers. Personal values are presented in the literature as the ultimate life goals individuals seek to attain in all aspects of their lives; hence, guide their behaviour. Based on this, the main objective of this study was to examine and identify the consumer (passenger) personal values that underpin the evaluation of airline service attributes used to choose an airline within the South African domestic passenger market. To achieve this objective, together with the secondary objectives, a quantitative descripto-explanatory research design was employed to guide data collection and analysis. A sample of 324 respondents was selected using a hybrid technique of convenience, and snowball sampling techniques and data were collected using both an online and hardcopy questionnaire. Data obtained were sorted and cleaned for analysis using the Statistical Product and Service Solutions (SPSS 26) and the Analysis of a Moment Structures (AMOS Version 26) software. Exploratory factor analysis (EFA) was conducted to assess factor structures of observed variables and identify latent constructs. The factorability of portrait value questionnaire (PVQ) items was determined using the confirmatory factor analysis (CFA). Hypotheses were tested using the backward multiple regression analysis, Whitney-Mann test, Spearman correlation and hierarchical regression with Hayes’ Process Macro. The study identified five of Schwartz’s 19 refined values as significantly influencing the evaluation and prioritisation of airline service attributes. A state of indifference among customers was found when the impact of airline service attributes was tested, with only onboard services found to significantly influence post-purchase outcomes such as satisfaction, loyalty and repeat purchase behaviour. It was also found that passengers did not distinguish between low-cost and full-service carriers. Income only moderated the influence of stimulation and self-direction thought values on airline service attributes while marketing communications effort was found to have a direct than a moderating role. In the main, these findings bring a novel and rich way of explaining airline choice through personal values. The results are essential for airline market segmentation, positioning and the development of airline products or features that match passenger desired life goals (personal values) which are touted as a guide to their choice behaviour. / Ukuqoka inkampani yezindiza ozoyisebenzisa kumayelana nokuthuthukisa umkhiqizo nabasebenzi bokumaketha kanye nabacwaningi. Phezu kokuba ukucwaninga ngezindiza nokuqokwa kwazo/ ikhwalithi yesevisi kukhomba kuphela izimfanelo zesevisi ezibalulekile kumakhasimende, lolu cwaningo lumbandakanye okungamagugu abantu ukunweba nokuletha izizathu zokuthi kungani izimfanelo zesevisi zenkampani yezindiza zingabalulekile noma zibalulekile kubagibeli. Okungamagugu abantu kwethulwe ngemibhalo kwaba ngamaphupho ekusasa ahlonzwayo ezimpilweni, ngakho,ebe eqondisa indlela yokuziphatha kwabo. Kuncike kulokhu, eyona nhlosongqangi yalolu cwaningo kwaku wukuhlola nokuhlonza okungamagugu omuntu ongumthengi (umgibeli) ukusekela ukuhlolwa kwezimfanelo zesevisi ezisetshenziswa ukukhetha inkampani yezindiza azoyisebenzisa ezimakethe zalezi ezihambela ngaphakathi eNingizimu Afrika. Ukufezekisa le nhlosongqangi kanye nezinye izizathu zocwaningo, idizayini yokucwaningo ye’quantitative descripto-explanatory’ isetshenziswe ukuqokelela idatha nokuhlaziya ulwazi. Isampula yababambe iqhaza abangama-324 ikhethiwe kusetshenziswa i hybrid technique of convenience, kanye nendlela yesampula yemihlathi eyazanayo (snowball sampling), kanti idatha iqoqwe ngakho kokubili, ‘online’ namaphepha anemibuzo ebuzelwa ukuthola okuthile. Idatha etholakele ihlukanisiwe yenzelwa ukuhlaziyeka kahle kusetshenziswa iStatistical Product neService Solutions (SPSS 26) kanye ne-Analysis of a Moment Structures (AMOS Version 26) software. I-Exploratory factor analysis (EFA) yenziwe ukuze kuhlolwe ukuthi izakhiwo eziyizimiso ukuqaphela okuguqukayo kwabuye kwaqashelwa ne-identify latent constructs. I- factorability yeportrait value questionnaire (PVQ) izinto zanqunywa kusetshenziswa iconfirmatory factor analysis (CFA). Umbono ube usuhlolwa kusetshenziswa ibackward multiple regression analysis, Whitney-Mann test, Spearman correlation ne hierarchical regression ene Hayes’ Process Macro. Lolu cwaningo lube nezinkomba ezinhlanu zika’Schwartz’s 19’ ezingamagugu acwengisisiwe abe nomthelela wazo ethonyeni lokuhlola nokubeka phambili kwezinkampani zezindiza izimfanelo zesevisi. Kutholwe isimo sokunganaki kubagibeli uma kuhlolwa izimfanelo zesevisi yenkampani yezindiza, kuphela nje isevisi yangaphakathi endizeni ithathwa njengebaluleke kakhulu enomthelela emiphumeleni yokuthenga kamuva okubalwa kukho ukwaneliseka kwabagibeli, ukwethembeka nokuphinda kuthengwe amanye ngokuzayo. Kutholakele ukuthi abagibeli abakwazanga ukwahlukanisa phakathi kosizo olusezingeni eliphansi nalolo olusezingeni eliphezulu. Inzuzo ibe nomthelela kuphela ekukhuthazeni isiqondiso ngasinye ngokwamagugu okuziphatha ezinsizeni zesevisi yenkampani yezindiza ngakolunye uhlangothi ezokuxhumana kwezezimakethe kuyimizamo etholakele kube neqondile kuneqhaza elisezingeni elilinganayo. Ngokwesidingo, lokhu okutholakele kwethula indlela entsha ecebileyokuchaza ukuqokwa kwezinkampani zezindiza ezisethenziswa abantu abawuhlobo oluthile. Imiphumela ibalulekile emakethe yezinkampani zezindiza ukuze kwahlukaniswe, kubekwe endaweni, kuthuthukiswe imikhiqizo yezinkampani zezindiza noma izinto ezithandwa abagibeli nezidingo zabo zempilo okuyizona eziwumhlahlandlela wokuqoka inkampani abazoyisebenzisa / Business Management / D. Com. (Business Management)

In order for the aviation industry to meet the targets of the Paris agreement and reach net-zero by 2050, significant amounts of greenhouse-gas emissions are to be reduced. However, as the industry is essentially dependent on conventional jet fuel, it becomes necessary for alternative technologies to develop and phase out fossil-based fuels. The thesis aims to provide valuable insights into the challenges and potentials of alternative technologies, which include sustainable aviation fuel (SAF), hydrogen, and electric-powered aviation. Additionally, the thesis investigated the Science-Based Targets initiative, and challenged the interim 1.5oC aviation pathway. The findings emphasize the crucial role of stakeholder cooperation in achieving net-zero emissions by 2050. Moreover, the thesis underscores the need for significant investments in alternative technologies, in order to enable growth and make the solutions increasingly attractive compared to conventional jet fuel. Collaboration and innovation are essential for attaining environmental targets while balancing economic growth. The thesis also highlights the urgency of policies and regulations to promote additional SAF production investments in order to vastly increase the supply. Furthermore, while the Science-Based Targets initiative (SBTi) is an effective means of securing airlines' commitment to the Paris Agreement, the thesis concludes that the SBTi 1.5oC interim pathway for airlines is overly optimistic. While the SBTi 1.5oC interim pathway’s SAF estimates for 2050 could be achieved, the thesis suggests around 2 to 4 times lower SAF supply for 2030 compared to the SBTi’s estimates. This further emphasizes the airlines' difficulties in following the 1.5oC pathway and the need for the industry to accelerate its transformation and make space for alternative solutions in order to meet the environmental targets. / För att flygindustrin ska nå målen i Parisavtalet och uppnå netto-nollutsläpp år 2050 måste betydande mängder växthusgasutsläpp minskas. Eftersom branschen är i grunden beroende av konventionellt flygbränsle blir det nödvändigt att utveckla alternativa teknologier för att fasas ut fossilbaserade bränslen. Avhandlingens syfte är att ge värdefulla insikter i utmaningarna samt möjligheterna med alternativa teknologier, vilket inkluderar hållbart flygbränsle (SAF), väte och elektriskt driven flygning. Dessutom undersökte avhandlingen Science-Based Targets-initiativet och utmanade det interimistiska 1.5°C-målet för flygindustrin. Resultaten betonar den avgörande rollen som samarbetande intressenter spelar för att uppnå netto-nollutsläpp år 2050. Dessutom understryker avhandlingen behovet av betydande investeringar i alternativa teknologier för att möjliggöra tillväxt och göra lösningarna allt mer attraktiva jämfört med konventionellt flygbränsle. Samarbetet och innovationen är nödvändiga för att uppnå miljömålen samtidigt som ekonomisk tillväxt möjliggörs. Avhandlingen betonar också brådskan med att införa policys och regleringar för att främja ytterligare produktion av hållbart flygbränsle (SAF) för att drastiskt öka tillgången. Medan Science-Based Targets-initiativet (SBTi) är ett effektivt sätt att säkerställa flygbolagens åtagande att uppfylla Parisavtalet, drar avhandlingen slutsatsen att SBTi:s interimistiska 1.5°C-mål för flygindustrin är alltför optimistiskt. Medan SBTi:s SAF-estimat för 2050 skulle kunna uppnås, föreslår avhandlingen en SAF-tillgång som är ungefär 2-4 gånger lägre för 2030 jämfört med SBTi:suppskattningar. Detta understryker ytterligare svårigheterna för flygbolag att hålla sig till 1.5oC målet samt nödvändigheten för flygindustrin att accelerera omställningen och skapa utrymme för alternativa lösningar för att uppnå miljömålen.

The aviation sector is in a critical position where it must switch to environmentally friendly alternatives in order to lessen its impact on the environment. The implementation of Sustainable Aviation Fuel (SAF) in airline business models is thoroughly examined in this thesis, which uses the Business Model Canvas (BMC) and the Triple Layered Business Model Canvas (TLBMC) as its primary conceptual frameworks. A thorough examination of the airlines' SAF pricing tactics and business models has been conducted, considering the sustainability of the environment, the economy, and society. This has made it possible to identify strategies that will effectively encourage the use of sustainable jet fuel. Through the examination and evaluation of aviation industry dynamics, legislation, and technical advancements, this research provides useful information to help direct strategic planning and decision-making within the aviation industry. The findings indicate that innovation, sustainability, and cooperation are essential for industry players to embrace in order to steer the aviation sector toward a more resilient and environmentally friendly future. The integration of sustainable aviation fuel within the airlines' business models represents a decisive step towards sustainability in the aviation industry. In this thesis, the Triple Layered Business Model Canvas TLBMC has been used to complement the traditional Business Model Canvas BMC. Using these frameworks together offers a holistic analysis of the environmental, economic and social impacts of SAF implementation on airlines such as Scandinavian Airlines SAS and BRA Braathens Regional Airlines. Sustainable jet fuel is used as a temporary solution to reduce the aviation industry's environmental impact. However, analysis and review of the sustainable fuel's life cycle from production to consumption is needed to be able to evaluate its environmental and social benefits. From an economic perspective, sustainable jet fuel production and availability is a major challenge for airlines. In order to overcome this challenge, innovative pricing strategies and cost-sharing initiatives are required in which various stakeholders from the aviation industry are involved. In summary, this thesis contributes to increased knowledge in changing business models in the aviation industry as well as an analysis of current price strategies for sustainable aviation fuel. Leveraging the insights from the TLBMC analysis of business models and pricing strategies for SAF integration, this research aims to inform strategic decision-making in the aviation sector and accelerate the industry's transition towards a more sustainable and environmentally conscious future. / Flygindustrin befinner sig i en avgörande position där behov för övergång till hållbara alternativ för att minska dess miljöpåverkan finns. Denna avhandling utgör en omfattande utforskning av hållbara flygbränslen införande inom flygbolagens affärsmodeller, med användning av både Business Model Canvas (BMC) och Triple Layered Business Model Canvas (TLBMC) som huvudramverk för analys. En noggrann analys av flygbolagens prisstrategier för hållbart flygbränsle och affärsmodeller har genomförts med hänsyn till miljömässiga, ekonomiska och sociala hållbarhetsaspekter. Detta har möjliggjort identifiering av effektiva tillvägagångssätt för att främja införandet av hållbart flygbränsle. Genom att utföra analyser och granskning av flygindustrins dynamik, riktlinjer och tekniska framsteg, bidrar denna forskning med praktiska insikter som syftar till att vägleda beslutsfattande och strategisk planering inom flygsektorn. Resultaten har visat på att det är avgörande för industrins intressenter att ta till sig innovation, hållbarhet och samarbeta för att föra flygsektorn mot en grönare och mer motståndskraftig framtid. Integrationen av hållbara flygbränsle inom flygbolagens affärsmodeller representerar ett avgörande steg mot hållbarhet inom flygindustrin. I denna avhandling har Triple Layered Business Model Canvas TLBMC, använts för att komplettera den traditionella Business Model Canvas BMC. Användning av dessa ramverk tillsammans erbjuder en holistisk analys av de miljömässiga, ekonomiska och sociala effekterna av SAF införande på flygbolag som Scandinavian Airlines SAS och BRA Braathens Regional Airlines. Hållbart flygbränsle används som en tillfällig lösning för att minska flygindustrins miljöpåverkan. Dock behövs det analys och granskning av det hållbara bränslets livscykel från produktion till konsumtion för att kunna utvärdera dess miljö och sociala fördelar. Från ett ekonomiskt perspektiv utgör det hållbara flygbränsle produktionen och tillgängligheten en  stor utmaning för flygbolagen. För att övervinna denna utmaningen krävs det innovativaprissättningsstrategier och kostnadsdelning initiativ där olika intressenter från flygindustrin är involverade. Sammanfattningsvis bidrar denna avhandling till ökad kunskap inom förändring av affärsmodeller inom flygindustrin samt en analys av nuvarande prisstrategier för hållbart flygbränsle. Genom att utnyttja insikterna från TLBMC-analysen av affärsmodeller och prissättningsstrategier för SAF-integration, syftar denna forskning till att informera strategiskt beslutsfattande inom flygsektorn och påskynda branschens övergång mot en mer hållbar och miljömedveten framtid.

L’objectif de cette thèse est d’analyser les contributions de Clément Colson à la science économique dans le but de mieux connaître sa pensée, de mieux connaître l’École libérale française au début du XXème siècle, d’étudier l’influence qu’a pu avoir cet auteur sur ses principaux élèves, Divisia, Roy et Rueff, et d’évaluer l’actualité de certaines de ses recommandations.Le premier chapitre montre quels sont les apports théoriques de Colson à la science économique.Pour ses élèves, son principal apport serait la théorie de la détermination conjointe du salaire et du taux d’intérêt. Nous montrerons que cette théorie est proche de la règle de gestion optimale en microéconomie attribuée à Clark ; nous verrons alors que l’on peut parler de découverte multiple.Colson est également intéressant au point de vue de la méthode utilisée. Nous verrons alors qu’il utilise les statistiques et les mathématiques dans ses développements : il est à l’origine d’une évaluation pionnière du revenu de la France, son enseignement impulse le calcul économique, il peut être considéré comme un précurseur de l’économétrie en France. Le deuxième chapitre montre que Colson développe la méthode de tarification des voies de communication exploitées en monopole de Jules Dupuit en proposant des moyens pratiques de révélation des préférences. Nous verrons également que cette théorie est reprise de nos jours avec le Yield Management et par les compagnies aériennes à bas coûts. Le troisième chapitre a pour but de voir comment Colson prend en compte la question sociale. Nous verrons qu’il défend une intervention de l’État plus importante que d’autres économistes libéraux afin d’éviter que les ouvriers ne se tournent vers le socialisme. Le quatrième chapitre étudie l’intervention de l’État préconisée par Colson dans le domaine des chemins de fer. Nous verrons que dans ce domaine où l’État est très présent, l’auteur souhaite le limiter. Il préfère ainsi la concession à la régie et souhaite la construction de nouvelles lignes uniquement si elles sont rentables. Nous verrons qu’à nouveau, la crainte du socialisme n’est pas étrangère à ses positions. Sur chacun des thèmes, nous verrons que Colson accorde à la pratique une place importante. Au niveau théorique tout part de l’observation et se termine par l’observation, au niveau pratique il est marqué par les préoccupations de son époque. / The object of this dissertation is to analyse the contributions of Clément Colson to the economics in order to be better acquainted with his thought, with the French Liberal School at the beginning of the 20th century, to see the influence he had on his main students, Divisia, Roy and Rueff, and to evaluate the actuality of his recomandations. The first chapter develops the Colson’s theoretical contributions.For his students, his main contribution would be the theory of the joint setting of wage and of the interest rate. We will explain this theory is close to the optimal management rule in microeconomics attributed to Clark; we will see we can speak then about multiple discovery.Colson is interesting too from the point of view of the method used. We will see he uses statistics and mathematics in his developments: he makes one of the first assesments of the French income, his lectures develop economics calculus, he can be seen as a precursor of econometrics in France. The second chapter shows that Colson develops the Jules Dupuit pricing method for means of communications exploited by a monopoly by proposing practical way of preferences revelation. We will show too that this theory is used nowadays with the Yield Management and by airline lowcost companies.The third chapter has for purpose to see how Colson takes into account the social question. We will see he argues for a more important State intervention than other liberal economists in order to avoid workers to turn to socialism. The fourth chapter is devoted to the State intervention recommended by Colson in the field of railways. We will see that in this field in which the State is very present, the author wishes to limit it. So he prefers the concession to the public exploitation and wishes construction of new railway lines just if they are profitable. We will see again that the fear of socialism is not stranger to his positions. On each theme, we will see that Colson gives an important place to the practice. At the theoretical level all starts and finishes with the observation, at the practice level he is influenced by the preoccupations of his time.

Les carteres d'aliances importen? Com afecten els recursos als quals les empreses accedeixen per diverses aliances estratègiques simultànies amb socis diferents a la creació de valor i a l'apropiació de valor? Les carteres d'aliances expliquen l'heterogeneïtat entre empreses respecte del valor que capten quan entren en noves aliances estratègiques? Aquesta tesi doctoral es basa en la teoria dels recursos i en la bibliografia sobre el comportament estratègic i les dinàmiques competitives, i presenta un model teòric que es refereix a la creació de valor i l'apropiació en empreses que accedeixen a recursos a través de diverses aliances simultànies amb socis diferents. El model mostra que la creació de valor en les carteres d'aliances és una funció del valor creat per combinacions sinergètiques de recursos que impliquen recursos als quals tenen accés diferents socis, com també del valor destruït a causa de la incompatibilitat entre la combinació de recursos d'una empresa focal i els recursos dels seus socis. Sobre la base d'aquest model teòric, s'han desenvolupat diverses hipòtesis en un ambient marginal en què una empresa connectada multilateralment afegeix una nova aliança estratègica a la seva cartera d'aliances. Per comprovar aquestes hipòtesis, s'ha emprat la metodologia de l'event study i s'han utilitzat dades de la indústria de els línies aèries globals sobre acords de code share subscrits entre 1994 i 1998. Els resultats mostren que el mercat recompensa les empreses que formen aliances amb socis que tenen recursos complementaris i poden aportar recursos que no només es poden combinar amb els recursos propis de l'empresa sinó també amb els relacionals i que també són compatibles amb els dels socis que formen l'aliança. D'altra banda, els resultats també mostren que el mercat penalitza les empreses que formen aliances que aporten recursos incompatibles amb les carteres d'aliances, atès que creen un conflicte competitiu amb alguns dels socis existents. Els resultats de la part empírica d'aquesta anàlisi abonen la tesis que les carteres d'aliances afecten els resultats de les empreses que entren en aliances estratègiques. Aquest estudi conclou que els recursos als quals es té accés per mitjà d'aliances entre empreses s'han d'avaluar no tan sols per les seves característiques pròpies y diàdiques sinó també en el context de les carteres d'aliances. / ¿Importan los portafolios de alianzas? ¿Cómo afectan los recursos a los que acceden las empresas por varias alianzas estratégicas simultáneas con socios diferentes a la creación de valor y a la apropiación de valor? Los portafolios de alianzas ¿explican la heterogeneidad entre empresas con respecto al valor que captan cuando entran en nuevas alianzas estratégicas? Esta tesis doctoral se basa en la teoría de los recursos y en la bibliografía sobre el comportamiento estratégico y las dinámicas competitivas, y presenta un modelo teórico que se refiere a la creación de valor y apropiación en empresas que acceden a recursos a través de varias alianzas simultáneas con socios diferentes. El modelo muestra que la creación de valor mediante un portafolio de alianzas es una función del valor creado por combinaciones sinergéticas de recursos que implican recursos a los cuales acceden diferentes socios, así como del valor destruido a causa de la incompatibilidad entre la combinación de recursos de una impresa focal y los recursos de sus socios. Sobre la base de este modelo teórico, se han desarrollado varias hipótesis en un ambiente marginal en el que una empresa conectada multilateralmente añade una nueva alianza estratégica a su cartera de alianzas. Para comprobar estas hipótesis se ha empleado la metodología del event study, y se han utilizado datos de la industria global de las aerolíneas sobre acuerdos de code share suscritos entre 1994 y 1998. Los resultados muestran que el mercado recompensa a las empresas que forman alianzas con socios que tienen recursos complementarios y pueden aportar recursos que no sólo pueden combinarse con los recursos propios de la empresa sino también con los relacionales y que también son compatibles con los de los socios que forman la alianza. Por otra parte, los resultados también muestran que el mercado penaliza a las empresas que forman alianzas que aportan recursos que son incompatibles con los portafolios de alianzas, en el sentido de que crean un conflicto competitivo con algunos de los socios existentes. Los resultados de la parte empírica de este análisis abonan la tesis de que los portafolios de alianzas afectan a los resultados de empresas que entran en alianzas estratégicas. Este estudio concluye que los recursos a los que se accede a través de las alianzas entre empresas han de evaluarse no sólo por sus características propias y diádicas sino también en el contexto de los portafolios de alianzas. / Do alliance portfolios matter? How do resources accessed from multiple simultaneous strategic alliances with different partners affect value creation and value appropriation? Do alliance portfolios explain heterogeneity across firms with respect to the value that they derive from entering into new strategic alliances? This dissertation builds on insights from the resource-based view of the firm and the strategic behaviour and competitive dynamics literature and advances a theoretical model that addresses value creation and appropriation in firms that access resources through multiple simultaneous inter-firm alliances with different partners. The model illustrates that value creation on the alliance portfolio level is a function of the value created from synergistic resource combinations involving resources accessed from different partners as well the value destroyed by incompatibilities between a focal firm's resource combinations and those deployed by its partners. Based on this theoretical model, empirically testable hypotheses are developed in a marginal setting, in which a multilaterally connected firm adds one new strategic alliance to its alliance portfolio. The hypotheses are tested using an event study method approach and data from the global airline industry on code share agreements formed between 1994 and 1998. The results show that the market on one side rewards firms entering into strategic alliances with partners that possess complementary resources and that contribute resources that cannot only be combined with firms' own but also existing relational resources and that are compatible with the firms' alliance portfolios. On the other side, results show that the market penalizes firms entering into alliances that contribute resources that are alliance portfolio incompatible in the sense that they create a competitive conflict with some of the existing alliance partners. The findings of the empirical part of this dissertation support the view that alliance portfolios affect the performance of firms entering into strategic alliances. This study concludes that resources accessed through inter-firm alliances should not only be evaluated on their standalone and dyadic attributes but also in the context of alliance portfolios.