Harry Markowitz (played by Marky Mark in the movie I am writing) helped lay a groundwork for Modern Portfolio Theory. Which of the statements below is/are associated with the Markowitz model?

1. The risk, return, and correlation of assets are important input variables in creating portfolios

2. Negatively correlated assets are necessary to reduce the risk of portfolios

3. In creating a portfolio, diversifying across asset types (e.g. stocks and bonds) is less effective then diversifying within an asset type