How long is the memory of the US stock market?

The Efficient Market Hypothesis (EMH), one of the most important hypothesis in financial economics, argues that return rates have no memory (correlation) which implies that agents cannot make abnormal profits in financial markets, due to the possibility of arbitrage operations. With return rates for the US stock market, we corroborate the fact that with a linear approach, return rates do not show evidence of correlation. However, linear approaches might not be complete or global, since return rates could suffer from nonlinearities. Using detrended cross-correlation analysis and its correlation coefficient, a methodology which analyzes long-range behavior between series, we show that the long-range correlation of return rates only ends in the 149th lag, which corresponds to about seven months. Does this result undermine the EMH?

Igreja de Nossa Senhora Mãe dos Homens (Avis): da história e memória do lugar à sua salvaguarda e valorização

A Igreja de Nossa Senhora Mãe dos Homens constituiu-se como o principal centro de romaria e peregrinação do concelho de Avis. No seu auge, nos inícios do século XX, as festividades ocuparam as primeiras páginas de jornais locais e distritais e abarcavam eventos como torneios de futebol, fanfarras, distribuição de enxovais a crianças carenciadas, entre outros, organizados pela Confraria com o mesmo nome, o que espelha a importância do culto. Porém, a construção da barragem do Maranhão, na década de 50 do século XX, veio isolar o local, aumentando as distâncias do mesmo à vila e aldeias mais próximas, diminuindo consequentemente a afluência de peregrinos e colocando o local em perigo do ponto de vista material e imaterial. Neste sentido, é imperativo que seja feito o seu levantamento histórico, arquitetónico, cultural e patrimonial, e que se lancem as bases para uma proposta de salvaguarda do património, em termos materiais e imateriais; Church of Nossa Senhora Mãe dos Homens (Avis): From the history and memory of the place to its safeguarding and enhancement ABSTRACT: The Church of Nossa Senhora Mãe dos Homens was established as the main pilgrimage center of the municipality of Avis. At its peak, in the early twentieth century, its festivities occupied the front pages of local and districtal newspapers and events such as football tournaments, fanfares, distribution of textiles to children in need, among others, were organized by the Confraternity of the same name, which reflects the importance of this investigation. However, the construction of the Dam of Maranhão, in the 50's of the twentieth century, came to isolate the site, increasing the distances to the nearby villages, thereby decreasing the influx of pilgrims and putting the local in danger from a material and immaterial point of view. Therefore, a historical, architectural and cultural survey of this site is imperative, as well as a proposal to the material and immaterial safeguard of this heritage.