We investigate tests for periodicity based on a spectral analysis of a time series, differentiating between global and local spectral-based tests. Global tests use information across the entire frequency band,whereas local tests are based on a window around the test frequency.We show that many...

While technological innovations are important for many industries, take-off sales for innovative products can have long lead times due to a variety of factors. This article identifies the main parameters affecting digital camera take-off sales in the US between 2001 and 2004. The study...

Biomedical studies suggest that a person?s behavior matters to health, but these studies usually treat human choice as exogenous. This study shows that individual choices on nutrient intake, exercise and use of medication are influenced by exogenous food prices, wages and nonlabor income. Using...

Domain reversal was performed on both near-stoichiometric and heavily Mg-doped lithium niobate crystals. H+ related defect structures in these two types of crystals were studied through the infrared absorption spectra. It is found that the intensity of some decomposed peaks of absorption band...