Davey, Startup, Zara, MacDonald, and Field (2003) were interested in the role of mood on the degree of compulsive checking in which a person engaged. (Compulsive checking is involved in a number of psychopathologies.) Three groups of 10 participants each listened to music designed to induce a positive, negative, or neutral mood. They were then asked to "list as many things around your home that you should check for safety or security reasons before you go away for three weeks." The dependent variable was the number of things listed. How would you analyze these data?