Studies of the effects of class attendance on class performance typically are quasi-experimental because students choose whether or not to attend class; that is, the samples are self-selecting. The lack of random assignment prevents one from establishing a causal relationship between attendance and performance. Relating attendance to performance…

The purpose of this survey was to identify the statistics texts most frequently used by psychology departments and to see if a typical survey of textbooks used by a partial sample of psychology departments would be accurate in describing the entire sample of departments. Partial returns resulted in a meaningful error. (RM)