(Dow Jones) Size does matter when it comes to investors' assets. And brokerage firms are implementing new programs that push their financial advisors to get rid of at least some small clients.

By reducing their concentration of small households by 1%, advisors can increase their production by $7,700, according to a study by PriceMetrix, a wealth management software provider.

The study looked at 15,000 advisor books at 15 of its brokerage firm clients and the ways in which the firms are attempting to decrease their percentage of client households with less than $100,000 in investable assets.

"Firms that were able to drive the most reduction in small household concentration used disincentives, which is just a fancy way of saying penalties," said Doug Trott, chief executive and president of PriceMetrix. "But they used a mix of carrots and sticks."

The most successful approach was giving advisors a target of small household concentration. One firm chose 15% as the target and motivated advisors and branch managers by not including business with households less than $50,000 in bonus calculations, according to the study.

That firm, which requested anonymity, saw the greatest percentage drop in small households, reducing its concentration by 14 percentage points in one year, reach a 24% concentration.

"Advisors and managers have very competitive behavior, so that is a great motivator," Trott said. "But there's also some coaching involved to help advisors understand the benefit of setting some minimums."

PriceMetrix provides software that enables advisors to see the revenue level over time of each of their households and how it compares to other similar accounts across the firm. They can use it to identify accounts that aren't generating revenue.

"Just like underperforming stocks, you would want to get them out of your portfolio," Trott said.

But many advisors express a strong allegiance to the lower-end clients who helped them build their book, even though they've now outgrown those relationships. Advisors also believe in that lottery-ticket client who will someday be worth millions.