Optimal statistical arbitrage trading of Berkshire Hathaway stock and its replicating portfolio.

In this paper, we make use of the replicating asset for statistical arbitrage trading, where the replicating asset is constructed by a portfolio that mimics the returns from a factor model. Using the replicating asset in the context of statistical arbitrage has never been done before in the literature. A novel optimal statistical arbitrage trading model is applied, and we derive the average transaction length and return for the Berkshire A stock and its replicating asset. The results show that the statistical arbitrage method proposed by Bertram (2010) is profitable by using the replicating asset. We also compute the average returns under different transaction costs. For the statistical arbitrage using the replicating asset of the factor model, average annual returns were at least 33%. Robustness is examined with the S&P500. Our results can provide hedge fund managers with a new technique for conducting statistical arbitrage.

Associations of eHealth Literacy With Health Services Utilization Among College Students: Cross-Sectional Study.

BACKGROUND: Electronic health (eHealth) literacy has become an important topic in health fields. Studies have found that individuals with higher eHealth literacy are more likely to use preventive care services and to have effective interactions with their physicians. In addition, previous studies have revealed a gender difference in the utilization of physician access and outpatient services. Nevertheless, few studies have explored the effect of the three levels of eHealth literacy (functional, interactive, and critical levels) on the four aspects of health services utilization (type, site, purpose, and time interval). It is unclear whether the associations between these three levels of eHealth literacy and the four aspects of health services utilization among college students are positive or negative. OBJECTIVE: The objective of this study was to investigate the associations among gender, eHealth literacy, and health services utilization. METHODS: We used the eHealth Literacy Scale, a 12-item instrument designed to measure college students' functional, interactive, and critical eHealth literacy, and the Health Services Utilization Scale, which is a 10-item instrument developed to measure the four aspects of health services utilization by college students. A nationally representative sample of 489 college students in Taiwan was surveyed. We conducted multiple regression analysis to examine the associations among gender, eHealth literacy, and health services utilization. RESULTS: The study found that being female was negatively related to the purpose aspect of health services utilization (t487=-2.85, P<.01). However, the R2 value of gender on the purpose aspect was low enough to be ignored. Critical (t484=2.98-4.23, P<.01) and interactive eHealth literacy (t484=2.43-2.89, P<.05) were related to three aspects of the health services utilization, and functional eHealth literacy was related to the purpose aspect (t484=-4.99, P<.001). CONCLUSIONS: This study showed that Taiwanese college students with interactive eHealth literacy were more likely to have a higher rate of outpatient care use. Moreover, Taiwanese college students with critical eHealth literacy were more likely to make full use of health services than those with functional eHealth literacy. Finally, the educated and age-restricted sample may attenuate gender disparities in health services utilization among Taiwanese college students.