In a market consisting of the three securities in Exercise 5.12, consider the portfolio on the efficient frontier with expected return μ_V = 21\%. Compute the values of γ and μ such that the weights w in this portfolio satisfy γwC = m− μu.
In a market consisting of the three securities in Exercise 5.12, consider the portfolio on the efficient frontier with expected return μ_V = 21\%. Compute the values of γ and μ such that the weights w in this portfolio satisfy γwC = m− μu.
Let m be the one-row matrix formed by the expected returns of the three
securities. By multiplying the γwC = m − μu equality by C^{−1}u^{T} and, respectively,C ^{−1}m^{T}, we get
μV (m − μu)C^{−1}u^{T} = (m − μu)C^{−1}m^{T} ,
since wu^{T} = 1 and wm^{T }= μ_V . This can be solved for μ to get
\mu =\frac{mC^{-1}(m^{T} − μ_V u^T )}{uC^{-1}(m^T− μ_V u^T)} \cong 0.142.
Then, γ can be computed as follows:
γ = (m − μu)C^{-1}u^T \cong 1.367.