为何b不对呢？

NO.PZ2019012201000079 问题如下 Whiof following is correregarng on Implementation Constraints? A.Twithe absolute risk will leto twithe return. B.Markowitz efficient frontier shows ththe relationship between return anrisk is convex. C.There is a level of leverage beyonwhivolatility reces expectereturns. C is corrent. Portfolios mfaimplementation constraints thcrease the IR if active risk increases beyona specific level; Portfolios with high absolute risk targets falimiteversification opportunities, whimleto a crease in the SR. There is a level of leverage beyonwhivolatility reces expectereturns. 主要是说当杠杆过高，虽然可能会带来收益，但是风险也会增加，带来更大的波动，反而会降低收益。打个比方，昨天跌了10%，今天涨了10%，看起来好像是一样的。但是实际不是一回事，反而是亏损的（亏损1%），加杠杆后会进一步降低收益。There mconstraints thprevent Manager A from scaling his active weights.So twithe absolute risk will not leto twithe return, Markowitz efficient frontier shows ththe relationship between return anrisk is concave. b为什么不对

NO.PZ2019012201000079 问题如下 Whiof following is correregarng on Implementation Constraints? A.Twithe absolute risk will leto twithe return. B.Markowitz efficient frontier shows ththe relationship between return anrisk is convex. C.There is a level of leverage beyonwhivolatility reces expectereturns. C is corrent. Portfolios mfaimplementation constraints thcrease the IR if active risk increases beyona specific level; Portfolios with high absolute risk targets falimiteversification opportunities, whimleto a crease in the SR. There is a level of leverage beyonwhivolatility reces expectereturns. 主要是说当杠杆过高，虽然可能会带来收益，但是风险也会增加，带来更大的波动，反而会降低收益。打个比方，昨天跌了10%，今天涨了10%，看起来好像是一样的。但是实际不是一回事，反而是亏损的（亏损1%），加杠杆后会进一步降低收益。There mconstraints thprevent Manager A from scaling his active weights.So twithe absolute risk will not leto twithe return, Markowitz efficient frontier shows ththe relationship between return anrisk is concave. 如题

NO.PZ2019012201000079 问题如下 Whiof following is correregarng on Implementation Constraints? A.Twithe absolute risk will leto twithe return. B.Markowitz efficient frontier shows ththe relationship between return anrisk is convex. C.There is a level of leverage beyonwhivolatility reces expectereturns. C is corrent. Portfolios mfaimplementation constraints thcrease the IR if active risk increases beyona specific level; Portfolios with high absolute risk targets falimiteversification opportunities, whimleto a crease in the SR. There is a level of leverage beyonwhivolatility reces expectereturns. 主要是说当杠杆过高，虽然可能会带来收益，但是风险也会增加，带来更大的波动，反而会降低收益。打个比方，昨天跌了10%，今天涨了10%，看起来好像是一样的。但是实际不是一回事，反而是亏损的（亏损1%），加杠杆后会进一步降低收益。There mconstraints thprevent Manager A from scaling his active weights.So twithe absolute risk will not leto twithe return, Markowitz efficient frontier shows ththe relationship between return anrisk is concave. 还是limitation of return achievebearing risk下面分的几点没有这么严格分类

NO.PZ2019012201000079问题如下Whiof following is correregarng on Implementation Constraints? A.Twithe absolute risk will leto twithe return.B.Markowitz efficient frontier shows ththe relationship between return anrisk is convex.C.There is a level of leverage beyonwhivolatility reces expectereturns. C is corrent. Portfolios mfaimplementation constraints thcrease the IR if active risk increases beyona specific level; Portfolios with high absolute risk targets falimiteversification opportunities, whimleto a crease in the SR. There is a level of leverage beyonwhivolatility reces expectereturns. 主要是说当杠杆过高，虽然可能会带来收益，但是风险也会增加，带来更大的波动，反而会降低收益。打个比方，昨天跌了10%，今天涨了10%，看起来好像是一样的。但是实际不是一回事，反而是亏损的（亏损1%），加杠杆后会进一步降低收益。There mconstraints thprevent Manager A from scaling his active weights.So twithe absolute risk will not leto twithe return, Markowitz efficient frontier shows ththe relationship between return anrisk is concave. 如标题 c没看懂 能在讲讲吗？

NO.PZ2019012201000079 问题如下 Whiof following is correregarng on Implementation Constraints? A.Twithe absolute risk will leto twithe return. B.Markowitz efficient frontier shows ththe relationship between return anrisk is convex. C.There is a level of leverage beyonwhivolatility reces expectereturns. C is corrent. Portfolios mfaimplementation constraints thcrease the IR if active risk increases beyona specific level; Portfolios with high absolute risk targets falimiteversification opportunities, whimleto a crease in the SR. There is a level of leverage beyonwhivolatility reces expectereturns. 主要是说当杠杆过高，虽然可能会带来收益，但是风险也会增加，带来更大的波动，反而会降低收益。打个比方，昨天跌了10%，今天涨了10%，看起来好像是一样的。但是实际不是一回事，反而是亏损的（亏损1%），加杠杆后会进一步降低收益。There mconstraints thprevent Manager A from scaling his active weights.So twithe absolute risk will not leto twithe return, Markowitz efficient frontier shows ththe relationship between return anrisk is concave. 马科维茨是个CONVX关系啊？