Not surprisingly, 91 percent of college students go online, according to the latest installment in the StudentWatch Campus Market Research series, which looks at students' attitudes toward advertising and promotion, online shopping behavior, and the factors that influence their purchase decisions. Regarding the effectiveness of advertising methods or product specifications, students ranked price and recommendations from friends or family as having the highest influence. Email ads and pop-ups were ranked as the lowest. On average, students report spending $410 a year on clothing. Students purchase about 16 percent of their textbooks online.