Victims may not have detected crimes or may not recognize that an incident is a crime. Victims also tend to fail to report information, because of fatigue, deliberate suppression, and difficulty in remembering events from the distant past. They may also recall incidents inaccurately because they unwittingly place the incident at the wrong point in time. Respondents with more education are generally more relaxed in interviews and more able to recall unwittingly place the incident at the wrong point in time. Respondents with more education are generally more relaxed in interviews and more able to recall details than are those with less education. Although the relative merits of personal and telephone interviews are the subject of disagreement, research has shown the usefulness of properly designed telephone interviews. Differences among interviewers may also influence data. All data contain errors, and the three main techniques used to conduct methodological research on victimization all have inherent problems. As a result, no improved method yet exists for measuring assault, a crime known to be incompletely reported. Followup interviews of victims to verify information from records is difficult, as are other methods of checking the accuracy of data. 100 references.