In the case of IFAs, there is evidence of reduced portfolio variance, systematic and unsystematic, as a result of such involvement, but no traces of such an effect remain in the bank advisor sample.

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That single objective would also negate the use of a portfolio that is able to deliver a minimum variance.

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One way for investors to mitigate high correlation, RBC argues, is concentrating the number of stocks in a portfolio and sacrificing the potential cost of somewhat higher return variance.

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Cost of carry on my bond portfolio of high yield paper is also minimal, but shows a net positive variance of over 500 basis points.

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