Empirical evidence indicates that trades by institutional investors have sizable effects on asset prices, generating phenomena such as index effects, asset-class effects and others. It is difficult to explain such phenomena within standard representative-agent asset pricing models. In this paper, we consider an economy populated by institutional investors alongside standard retail investors. In...

Existing studies find that compared to non-lottery stocks, lottery-like stocks tend to be overpriced and earn lower subsequent returns, probably due to investor preferences for lottery-like assets. We argue that investor preferences for holding speculative assets are more pronounced ahead of firms’ earnings announcements, probably due to lower inventory costs and immediate payoffs. We show that...

Flagellate infections were found in 1,063 of 18,895 sand flies collected in the states of Amazonas, Pará, Rondonia and Acre, Brazil. Infection rates were 13.4% (species group Shannoni); 7.5% (subgenus Nyssomyia); 6.7% (subgenus Lutzomyia series Cruciata); 0.5% (genus Psychodopygus) and 3.1% for other sand flies (various subgenera). Leishmania braziliensis guyanensis and L. mexicana amazonensis ...

Statistical analysis of financial time series is studied. We use wavelet analysis to study signal to noise ratios along with auto-correlation function to study correlation length for time series data of daily stock prices for specific sectors of the market. We study the ”high beta” stocks versus the ”low beta” stocks. We sample ten companies from both of these sectors. We find that the signal t...

Drosophila stocks bearing compound chromosomes, single molecules of DNA that carry the genomic complement of two chromosomes, are useful tools for studying meiosis and mitosis. However, these stocks cannot easily be crossed to stocks with regular chromosomes, due to the lethality of the resulting whole-chromosome aneuploidy. This prevents the examination of interesting genetic variants in a com...

The finding that stocks with high idiosyncratic volatility tend to have low future returns, as first documented in Ang, Hodrick, Xing, and Zhang (2006), has been dubbed as the idiosyncratic volatility anomaly in the finance literature. Several studies have since explored various potential explanations of the anomalous relation between idiosyncratic volatility and stock returns. Some studies eve...

Correlations between U.S. stocks and the aggregate U.S. market are much greater for downside moves, especially for extreme downside moves, than for upside moves. We develop a new statistic for measuring, comparing, and testing asymmetries in conditional correlations. Conditional on the downside, correlations in the data differ from the conditional correlations implied by a normal distribution b...

We analyze the effects of differences of opinion on the dynamics of trading volume in stocks and options.We find that disagreements about the mean of the currentand next-period public information lead to trading in stocks in the current period but have no effect on options trading. Without options, we find that disagreements about the precision of all past and current public information affect ...

Thirty-six Trypanosomatidae stocks isolated from various hosts and geographical areas in Colombia and 7 others from Bolivia, Chile, Honduras and Panama have been surveyed by Multilocus Enzyme Electrophoresis (MLEE). Part of the Colombian stocks were previously characterized by morphology and biological behavior as belonging to Trypanosoma cruzi and Trypanosoma rangeli taxa, others were unknown ...

Randomly amplified polymorphic DNA (RAPD) has emerged as an effective genetic marker for analysis of Trypanosoma cruzi population variability. This method has been used to study the genetic variability of Mexican T. cruzi stocks and to relate these results to previous classifications. High clonal diversity was observed among the Mexican populations: 24 RAPD types were scored among 56 stocks ana...