We examine whether systematic higher moments capture beta asymmetry in an asset pricing model whereby the conditional beta of a risky asset increases (decreases) during a bear (bull) market state. We first provide a simple conceptual outline from the microeconomic literature to show that beta asymmetry is driven by time-varying higher-order risk preferences (prudence and temperance) across different market states. We then empirically relate these higher-order risk preferences to systematic skewness and systematic kurtosis. We find that beta asymmetry in Australian stock returns cannot be explained by Carhart (1997) 4-factor model but is subsumed by systematic higher moments. Accounting and Finance 54 (2014) 779-807 1 Fabozzi and Francis (1977) first develop a dual-beta model based on the Sharpe's oneperiod CAPM. Their model, however, does not allow the intercept term to vary with beta across bull and bear market environments.

We investigate the coexistence of momentum and contrarian strategies in the Australian equity market from 1992 to 2011. We show that contrarian strategies prevail in the short-term investment horizon while momentum strategies dominate in the intermediate-and long-term horizons. However, only short-term contrarian strategies significantly outperform the simple buy-and-hold strategy of investing in the market index over the same period. Further examination of these strategies show that the Australian mining sector undermines the performance of momentum while enhancing performance of contrarian strategies. Lastly, using both parametric and non-parametric approaches, we show that these strategies' returns are persistent anomalies and not completely explained by standard return-generating models.

DDoS is one of the most dangerous methods to attack victim network because it uses a vast quantity of distributed agents to make victim paralyze. This paper gives a DDoS defense method which is based on "pushback and communicate" idea (PaC method). When the gateway of victim detects DDoS attack, it has to listen on interfaces to define the neighbors from which DDoS packets come. Those neighbors will receive DDoS information and do same things the victim's gateway does. By repeating that work, PaC can find the exact way DDoS packets had passed through. All routers then continue creating their own filters before sending DDoS information to their next neighbors.

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Leuven's Den Hoorn brewery, now AB Inbev SA, has become the world's largest brewing group by far, but critics say the company overpaid for its acquisitions. In this article, we study typical stock market reactions to the many takeover announcements by AB Inbev and the industry's runner-up, Heineken. Unlike Heineken's, the market leader's takeover announcements were met by, on average, a –2% price reaction in the stock market in the announcement month, but most of that is already undone in the next month. For Heineken, the same pattern shows up, only faster: the V-shaped reaction takes a few weeks rather than a few months. Such V-reactions may actually reflect a temporary rise in uncertainty rather than overpaying. The finding that reactions are reversed and heterogeneous across firms, raises issues of interpretation and optimal test design of event studies. (JEL Classifications: G12, G14, G17)