Reduced-bias tail index estimation and the jackknife methodology

In the context of regularly varying tails, we first analyze a generalization of the classical Hill estimator of a positive tail index, with members that are not asymptotically more efficient than the original one. This has led us to propose alternative classical tail index estimators, that may perform asymptotically better than the Hill estimator. As the improvement is not really significant, we also propose generalized jackknife estimators based on any two members of these two classes. These generalized jackknife estimators are compared with the Hill estimator and other reduced-bias estimators available in the literature, asymptotically, and for finite samples, through the use of Monte Carlo simulation. The finite-sample behaviour of the new reduced-bias estimators is also illustrated through a practical example in the field of finance.     

Stock Market Mean Reversion and the Optimal Equity Allocation of a Long-Lived Investor

This paper solves numerically the intertemporalconsumption and portfolio choiceproblem of an infinitely-lived investor whofaces a time-varying equity premium.The solutions we obtain are very similarto the approximate analytical solutionsof Campbell and Viceira (1999), except atthe upper extreme of the state spacewhere both the numerical consumption andportfolio rules flatten out.We also consider a constrained version ofthe problem in which the investor facesborrowing and short-sales restrictions.These constraints bind when the equitypremium moves away from its mean in eitherdirection, and are particularly severe forrisk-tolerant investors. The constraints havesubstantial effects on optimalconsumption, but much more modest effects onoptimal portfolio choice in theregion of the state space where they are notbinding.     

I do not own a car any more: An analysis of possessions’ disposal and changes in consumers’ identities

This research aims to understand the process of cars' disposal, its context, its influences and its impacts on the meanings for consumers and their identities, as well as the new behaviours of these consumers when living without their car(s). We conducted, analysed and interpreted 20 in‐depth interviews with consumers that had previously owned at least one car and had no financial reasons for disposing of their car(s), but had decided to do it, and started to live without them, adopting alternative methods of transportation. Our findings show that these consumers faced a complicated process regarding the disposal of their car(s) but, due to the changes in their circumstances, they re‐signified relevant concepts that were connected to the ownership of a car: Their perception of freedom, comfort, safety and status changed during and after the disposal of their car(s). We also noticed that there were implications in terms of changes in their attitudes and behaviour as both citizens and consumers. As a contribution to the literature, our findings indicate that the re‐signifying of concepts related to possession of the object as well as changes in attitudes and behaviours that consumers undergo in the postdisposal stage, must be included in the model proposed for evaluating consumer behaviour in product disposal.     

The influence of user-supplier relationship on innovation dynamics of Oil & Gas industry

ABSTRACT

This paper analyses the role of user-supplier relationships in the innovation dynamics of the Oil and Gas (O&G) industry, from an analysis supported by R&D and patent application data. This paper points to some recent interesting phenomena in the O&G sector, such as: (i) the remarkable advancement of two Chinese oil companies; (ii) the significant growth in O&G companies’ technological engagement in exploration and production (E&P) from the 2000s; (iii) the non-negligible increase in the application of O&G companies’ patents for renewable energy. Moreover, by working with the oil and gas chain complete, we show that the performance of the companies oil and gas equipment and services industry (O&GES) is restricted to the upstream activities. Finally, we bring up some arguments that have as objective relativise the typology of R&D intensity adopted by OECD.     

Mergers and Acquisitions and Market Volatility of Brazilian Banking Stocks: An Application of GARCH Models

The main objective of this research was to investigate the impacts caused by announcements of mergers and acquisitions (M&As) on the volatility of the returns of Brazilian bank stocks from 1994 to 2015. In order to achieve the proposed objective, this study applied Generalized Autoregressive Conditional Heteroscedastic (GARCH) class models to the series to model their volatility. Our results confirmed the impact of the announcement of M&As on volatility. They suggest that M&A announcements are expected to cause a negative reaction if related to an expansion or a deal involving a less-well known bank, and a positive reaction if it involves well-known bank with good reputation—a higher level of confidence and a lower level of information asymmetry for investors.     

Exploiting short-run predictability

This paper measures the utility gains from exploiting short-run predictability in the volatility of stock returns in a dynamic model in the the presence of transaction costs, short-selling constraints and estimation risk. We find that utility gains are quite significant, both ex ante and out-of-sample.     

The exit decision in the European venture capital market

This article analyses the exit decision in the European venture capital market, studying when to exit and how it interacts with the exit form. Using a competing risks model we study the impact on the exit decision of the characteristics of venture capital investors, of their investments and of contracting variables. Our results reveals that the hazard functions are non-monotonic for all exit forms and suggest that, in Europe, Initial Public Offering candidates take longer to be selected than trade sales. Moreover our results show that, in Europe, venture capitalists associated with financial institutions have quicker exits (stronger for trade sales), and highlight the importance of contracting variables on the exit decision. An unexpected result is that the presence on the board of directors leads to longer investment durations.     

Running for pleasure or performance? How store attributes and hedonic product value influence consumer satisfaction

Previous retailing studies have linked consumer satisfaction to perceived hedonic or utilitarian product value. This research extends previous studies by examining how the context in which the product is purchased (store attributes) and product value influence consumer satisfaction. We conducted a field study with 213 consumers attending two major running events. The findings from structural equation modelling suggest that a specific combination of store attributes (tangible and intangible) and hedonic product value has a positive influence on satisfaction. Results also show that tangible store attributes have a stronger positive impact on utilitarian (vs. hedonic) product value, and that intangible store attributes have a positive impact on hedonic product value. However, we found that only hedonic product value has a positive impact on satisfaction. This research contributes to theory by showing that a match between store attributes (tangible and intangible) and hedonic product value can positively influence satisfaction. In managerial terms, the findings provide insights on how to improve consumer satisfaction in retail environments through store attributes and hedonic product value.     

Characteristics of Portuguese public‐sector project managers: Toward closing the effectiveness gap

Using a sample of 102 Portuguese public‐sector officials with project management experience, this study examines the characteristics of effective project managers in the Portuguese public sector. Factor‐analysis procedures are used to identify the factors related to areas of knowledge relevant to effective project management. The results appear to stress the increasing importance of people, organizational, and leadership skills in the effective management of today's complex and dynamic projects.