The fundamental purpose of investing in stocks is to make a profit. But the stock investment, income always accompanies risk. In order reduce risk greater returns, investor will be two or more portfolio together invest. This study examines return and using minimal variance maximum Sharpe ratio model, based on Markowitz mean-variance theory, identify best for given preference. model risk-averse ...

This paper presents results on the simulation of the evacuation of the city of Padang with approximately 1,000,000 inhabitants. The model used is MATSim (www.matsim.org). Three different strategies were applied: shortest path solution, user optimum, system optimum, together with a constraint that moves should reduce risk whenever possible. The introduction of the risk minimization increases the...

Many populations in nature are fragmented: they consist of local populations occupying separate patches. A local population is prone to extinction due to the shot noise of birth and death processes. A migrating population from another patch can dramatically delay the extinction. What is the optimal migration rate that minimizes the extinction risk of the whole population? Here, we answer this q...