Offer your thoughts or opinion on the input financial query or topic using your financial background.

Does financing a portfolio on margin affect the variance of a portfolio?
Yes, more leverage increases the variance of your individual portfolio (variance of your personal net worth). The simple way to think about it is that if you only own only 50% of your risky assets, then you can own twice as many risky assets. That means they will move around twice as much (in absolute terms). Expected returns and risk (if risk is variance) both go up. If you lend rather than borrow, then you might have only half your net worth in risky assets, and then your expected returns and variation in returns will go down. Note, the practice of using leverage differs from portfolio theory in a couple important ways.