8月全球股市下跌是人为抛售决定所致_时事

8月全球股市下跌是人为抛售决定所致

宏观对冲基金和平衡型共同基金(两者均可投资于各种资产类别)在8月期间采取紧急行动降低股票亏损风险。各投资组合的整体股票贝塔系数(衡量股指变动与个别投资基金变动之间的关系)在8月份急剧下降。

The bank also found betas for so-called long-short hedge funds declined sharply in August as managers reacted to volatility by paring bets. JPMorgan’s work is based on a regression analysis of index movements, such as the HFRX, a hedge fund benchmark, as a proxy for fund holdings.

摩根大通还发现，所谓的多空对冲基金的贝塔系数也在8月份大幅下降，原因是经理人纷纷通过平仓对波动性作出反应。该行的研究是基于对指数变动(如对冲基金基准指数HFRX)的回归分析，将指数作为基金持股的代表。

The beta for risk parity funds, by comparison, declined only a small amount. Such funds have attracted attention owing to attempts to blend stocks, bonds and commodities, with selective use of leverage to produce returns similar to traditional investment products, while taking less risk.

相比之下，风险平价基金的贝塔系数仅小幅下降。近年此类基金受到关注，因为它们试图混合持有股票、债券和大宗商品，然后选择性地使用杠杆，在降低风险的同时带来与传统投资产品相仿的回报。

Leon Cooperman, the founder of Omega Advisors, last week blamed “systemic/technical investors for the August sell-off. The veteran investor pointed to influential risk parity strategies pioneered by hedge funds such as Bridgewater, as well as so-called CTAs, funds specialising in trading derivatives based on computer models.