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"AA rated CDOs currently offer significant relative value for long-term investors as the yield spread reflects a BB default rate expectation for the underlying collateral. "这句话什么意思呢?我读完感觉CDO是高估,underlying collateral 才是低估的。麻烦解释一下A选项。
C选项中,为什么correlation increase就会使得mezzz value 增加呢?