The article discusses a new way to choose investments that focuses on reducing the risk of losing money, especially when dealing with extreme events in the financial market. They call this the mean-downside risk model. By analyzing the tails of financial assets, they figure out the best mix of investments to minimize the downside risk of a portfolio while aiming for a certain return. Just like how Markowitz portfolio theory shows a trade-off between expected return and risk, this model also finds a balance between return and downside risk. The researchers prove mathematically and show through real-world data that there is a unique solution for the best mix of investments to minimize downside risk.