Think for the perspective of an investment fund such as Acadian Asset Management (not a financial advisor).

What is the most important dimension of professional management of stock portfolios?

How do professional managers control the cost of their portfolio management process?

Assume a manager controls the cost of his portfolio using the approach we discussed. Assume this manage will rebalance his portfolio every week. Does this necessary mean that the manager will incur in very high transaction costs?

Hint: Will rebalancing (i.e., running cost-aware optimization) necessarily lead to trading?