Computation of expected returns, variances and covariance of stocks

Tangency Portfolio Problem. From finance.yahoo.com collect 10 years of monthly returns for four stocks. Sample of 10 years of monthly data should be a pretty reasonable estimate of expected returns, variances, and covariance.

Compute your complete portfolio. Choose your own risk aversion coefficient A. assume that the T-bill rate is 0.5%¹. You have to report

i. Corresponding weights of the Tangency and T-Bill portfolios;

ii. Expected return and volatility of the complete portfolio.

Hint: using vector formulation, it is very easy to compute portfolio\'s variance! If ω is the N X 1 vector of portfolio weights and Ω is the N X N variance-co variance matrix, then the portfolio variance is σ_p² = ω\'Ωω and portfolio volatility is σ_p = (ω\'Ωω)^1/2.