University of Greenwich

About: University of Greenwich is a education organization based out in London, United Kingdom. It is known for research contribution in the topics: Population & Context (language use). The organization has 3749 authors who have published 9958 publications receiving 234340 citations.

Weak-form market efficiency and calendar anomalies for Eastern Europe equity markets

Abstract: In this article we test the weak form of the efficient market hypothesis for Central and Eastern Europe (CEE) equity markets for the period 1999-2009. To test weak-form efficiency in the markets, this study uses autocorrelation analysis, runs test and variance ratio test. We find that stock markets of the CEE do not follow a random walk process. THis is an important finding for the CEE markets as an informed investor can identify mispriced assets in the markets by studying the past prices in these markets. We also test the presence of daily anomalies for the same group of stock markets using a basic model and a more advanced Generalised Autoregressive Conditional Heteroscedasticity in Mean ((GARCH-M) model. Results indicate that day-of-the-week effect is not evident in most of markets except for some. Overall results indicate that some of these markets are not weak and an efficient and informed investor can make abnormal profits by studying the past prices of these assets in these markets.

A comparison of the feeding behaviour of tsetse and stable flies

Abstract: In Zimbabwe, observations were made of the behaviour of individual stable flies (Stomoxys spp.) (Diptera: Muscidae) and tsetse (Glossina spp.) (Diptera: Glossinidae) feeding on cattle during the wet (Stomoxys and tsetse) and dry (tsetse only) seasons. For Stomoxys landing on adult cattle, only 27% took a full meal (mean feeding time = 147 s). Most Stomoxys left the host before completing their meal, largely due to disturbance by the host's defensive behaviour (24%, mean time = 59 s) or other flies (44%, 71 s). The probability of a Stomoxys leaving the host progressively increased with time. Simultaneous observations of tsetse showed that, compared to Stomoxys, their feeding success was lower (15%), feeding was interrupted earlier (33 s) and the time taken to complete a meal was shorter (109 s). Further studies of tsetse across different seasons and hosts showed that feeding success varied according to host age (adult = 7%; calf = 3%) and was negatively correlated with the frequency of host defensive behaviour and the relative abundance of non-biting Diptera. Disturbances were more often caused by host behaviour (69%) than other flies (31%) and the probability of tsetse leaving decreased with time on the host. Overall, these results suggest that tsetse and Stomoxys have different feeding strategies. In particular, tsetse appear to be more responsive to host defensive behaviour, which reduces their feeding success relative to Stomoxys. These behavioural differences are consistent with the respective life-history characteristics of Stomoxys and tsetse.

The effects of microdose LSD on time perception: a randomised, double-blind, placebo-controlled trial.

Abstract: Previous research demonstrating that lysergic acid diethylamide (LSD) produces alterations in time perception has implications for its impact on conscious states and a range of psychological functions that necessitate precise interval timing. However, interpretation of this research is hindered by methodological limitations and an inability to dissociate direct neurochemical effects on interval timing from indirect effects attributable to altered states of consciousness. We conducted a randomised, double-blind, placebo-controlled study contrasting oral administration of placebo with three microdoses of LSD (5, 10, and 20 μg) in older adults. Subjective drug effects were regularly recorded and interval timing was assessed using a temporal reproduction task spanning subsecond and suprasecond intervals. LSD conditions were not associated with any robust changes in self-report indices of perception, mentation, or concentration. LSD reliably produced over-reproduction of temporal intervals of 2000 ms and longer with these effects most pronounced in the 10 μg dose condition. Hierarchical regression analyses indicated that LSD-mediated over-reproduction was independent of marginal differences in self-reported drug effects across conditions. These results suggest that microdose LSD produces temporal dilation of suprasecond intervals in the absence of subjective alterations of consciousness.