Robustness of stationary tests under long-memory alternatives

This paper investigates the presence of long memory in financiaI time series using four test statistics: V/S, KPSS, KS and modified R/S. There has been a large amount of study on the long memory behavior in economic and financiaI time series. However, there is still no consensus. We argue in this paper that spurious short-term memory may be found due to the incorrect use of data-dependent bandwidth to estimating the longrun variance. We propose a partially adaptive lag truncation procedure that is robust against the presence of long memory under the alternative hypothesis and revisit several economic and financiaI time series using the proposed bandwidth choice. Our results indicate the existence of spurious short memory in real exchange rates when Andrews' formula is employed, but long memory is detected when the proposed lag truncation procedure is used. Using stock market data, we also found short memory in returns and long memory in volatility.

Improvements and alternatives to intellectual property: a survey

Uma parcela importante do crescimento econômico é devida a inovações. Esta dissertação revisa a literatura recente em propriedade intelectual. Esta revisão discute os seguintes artigos: Kremer (1998), Boldrin e Levine (2001), Kremer (2001), Shavell e Ypersele (2001), Lerner (2002) e DiMasi, Hansen e Grabowski (2003). Estes contém tanto artigos empíricos quanto teóricos. Na primeira categoria está um artigo sobre efeitos na inovação de mudanças na força das patentes e outro sobre custo de desenvolver novos medicamentos. Os estudos teóricos propõem melhorias e alternativas ao sistema de patentes, por exemplo, recompensas opcionais, compras de patentes, eliminação de patentes em alguns setores e compromisso de compra prévio.

The market strategies alternatives of an e-business start-up in Brazil

The e-business market is one of the fastest growing markets in Brazil, with e-business sales accounting for BRL 14.8 billion in 2010 and a growth of 40% per year (+1000% over the past 7 years). Sales-event clubs and collective bargaining websites are one of the most dynamic segments of the e-business market: the number of new players is increasing rapidly, with over 1200 collective bargaining websites currently operating in Brazil. In that context, growth and differentiation seem to be two key success factors for Coquelux. According to webshopper (23rd Edition, e-bit), growth can be achieved by targeting middle and low-income consumers from class C, who represent 50% of the total e-commerce sales. But Coquelux, which is specialized in desire and luxury brands, has built its reputation and competitive advantage through its “exclusivity”, by targeting wealthier consumers from classes A and B who are attracted by its fashionable and high-end positioning. The evolution (growth?) of this market and the development of its competition naturally raise a strategic question for Coquelux’s managers: can Coquelux grow and still maintain its competitive advantage? Should it grow by expanding its consumer base to class C? If so, how? Consumers from classes A, B or C must be targeted through the same online communication channels. Recent studies from the ABEP/ABIPEME emphasized the importance of social networks as a tool for converting new clients and gaining their loyalty, regardless of their social class. However, high-income and low-income e-consumers do not have the same consumption habits, do not respond to the same type of marketing strategies, and most importantly, do not share the same values. Thus, it seems difficult to expand Coquelux’s consumer base to class C without changing its marketing strategies and altering its image Three options were identified for Coquelux: reinforcing its leadership on the luxury segment and focusing on a small niche market (1), which would threaten its survival in the long run; completely changing its strategy and competing for a mass market through commercial brands (2), which requires major financial investments that managers don’t have access to; or finding an intermediary solution (3). This thesis’ recommendation for the third option consists in focusing on premium brands (rather than luxury) in order to increase sales volume (Coquelux’s most profitable sales happened with local desire brands) with products that appeal to class B but also attract the emerging class C which is looking for brand recognition. It could thus implement a slow entry strategy towards the mass market without damaging its main competitive advantage.