Criticisms of the RAND Second Inmate Survey have implied that these problems may have led to inflated estimates of lambda. In the current study, the authors randomly assigned prison inmates to two groups, one to be interviewed using the RAND method for measuring crime rates, and one to be interviewed using the authors' modified month- by-month method. The participants were 700 convicted male offenders sentenced to the Nebraska Department of Corrections. The men admitted to the Diagnostic and Evaluation Unit for new offenses were interviewed until the required sample size was reached. The authors expected that their month-by-month method would produce lower estimates of lambda. however, results revealed that the two distributions of lambda did not differ significantly from each other, suggesting that the RAND results are very robust. Tables, figures, and 14 references (Author abstract modified)