Small-cap guru Jim Oberweis says the retail and advertising industries are home to big changes these days, and that smart investors can profit from those changes.

“Radical changes is a fact of life for anyone in the retailing and advertising sector these days,” Oberweis writes in his latest Forbes column. “You can thank technology, which has improved business prospects and efficiency and, at the same time, made it intensely more competitive. This month I am focusing on small-cap companies in advertising and retailing that are capitalizing on these sweeping changes and seizing opportunities for rapid growth here and abroad.”

Among the firms Oberweis examines: Los Angeles-based The Rubicon Project, which developed technology that automates the buying and selling of advertising. “Although the ad-tech space is fragmented and competitive, few are as tightly integrated with major publishers as Rubicon is,” Oberweis says. “Additionally, Rubicon is viewed by some publishers as the ‘non-Google’ option (competitor DoubleClick is owned by Google). With the real-time bidding market estimated to grow 50% annually to $20 billion by 2017, Rubicon is strategically positioned between buyers and sellers to grab some of this money. Shares trade for 38 times my forward estimate of $0.47, for estimated growth of 48% in revenues and 161% in EPS.”