Among the earnings stories for Friday, May 8, from AP Financial News: NEW YORK (AP) ¿ Shares of Luminex Corp., which makes testing systems for biotechnology companies, fell a day after it reported lower-than-expected first-quarter results. TULSA, Okla. (AP) ¿ Arena Resources Inc., an oil and natural gas exploration company, said its first-quarter profit sank 65 percent as commodity prices plummeted. CINCINNATI (AP) ¿ Scripps Networks Interactive Inc. reported a 10 percent drop in first-quarter earnings, dragged down by the slumping advertising market and heavy competition for its online comparison shopping Web sites. ENGLEWOOD, Colo. (AP) ¿ Entertainment media company Liberty Media Corp. posted a mixed quarter for revenue, reporting growth at two smaller units but a decline in its largest division as the poor retail market hurt its QVC Shopping Network. PEABODY, Mass. (AP) ¿ Beacon Roofing Supply Inc. said its fiscal second-quarter loss narrowed, helped by higher residential roofing sales and strong demand in markets affected by Hurricane Ike. ATLANTA (AP) ¿ Energy provider Mirant Corp. reported a net profit of $380 million in the first quarter, bouncing back from a loss of $152 million in the year-earlier period. The company also announced senior management changes.