NO.PZ2019012201000075
问题如下：
Chen and Garcia next discuss characteristics of long–short and long-only investing. Garcia makes the following statements about investing with long–short and long-only managers:
Statement 1 A long–short portfolio allows for a gross exposure of 100%.
Statement 2 A long-only portfolio generally allows for greater investment capacity than other approaches, particularly when using strategies that focus on large-cap stocks. Which of Garcia’s statements regarding investing with long–short and longonly managers is correct?
选项：
A. Only Statement 1
B. Only Statement 2
C. Both Statement 1 and Statement 2
解释：
C is correct. Both Statement 1 and Statement 2 are correct.Statement 1 is correct because, similar to a long-only portfolio, a long–short portfolio can be structured to have a gross exposure of 100%. Gross exposure of the portfolio is calculated as the sum of the long positions and the absolute value of the short positions, expressed as percentages of the portfolio’s capital.
Gross exposure = Long positions + |Short positions|
Gross exposure long-only portfolio = 100% (Long positions) + 0% (Short positions) = 100%
Gross exposure long–short portfolio = 50% (Long positions) + |–50%| (Short positions) = 100%
Statement 2 is correct because long-only investing generally offers greater investment capacity than other approaches, particularly when using strategies that focus on large-cap stocks. For large institutional investors such as pension plans, there are no effective capacity constraints in terms of the total market cap available for long-only investing.
比如手里100万股票头寸，我卖掉表现最不好的30万，去买表现最好的，总头寸应该是130万，为什么会是100%呢？ 看了老师前面回答其他同学的，卖掉手里50%，去买50%，加起来是100%。那是不是忽略了手里原来的50%？如果是把手里原来50%加上，应该也是150%啊
