Alcohol and Marijuana Use Among College Students: Economic Complements or Substitutes?

College campuses have been cracking down on underage and binge drinking in light of recent highly publicized student deaths. Although there is evidence showing that stricter college alcohol policies have been effective at discouraging both drinking in general and frequent binge drinking on college campuses, recent evidence from the Harvard School Of Public Health College Alcohol Study (CAS) shows that marijuana use among college students rose 22 percent between 1993 and 1999. Are current policies aimed at reducing alcohol consumption inadvertently encouraging marijuana use? This paper begins to address this question by investigating the relationship between the demands for alcohol and marijuana for college students using data from the 1993, 1997 and 1999 CAS. We find that alcohol and marijuana are economic complements and that policies that increase the full price of alcohol decrease participation in marijuana use.