ST. CLOUD, Minn. — Coborn’s here has chosen the Revionics price optimization software service and will begin implementing it over the next 30 days, Revionics, Sacramento, Calif., announced yesterday. Coborn’s, which operates 33 stores over two states, including multiple retail formats, will use the system to focus on margin improvement. “Revionics provided an answer to a very difficult question, ‘How do you increase margins in the face of competitive challengers?’” said Andy Knoblauch, vice president of sales, marketing and merchandising for Coborn’s, in a statement. “Revionics will help us to be agile in the face of competition without giving away unnecessary margin.” Revionics offers its service via a weekly, Web-based subscription model.