Several researchers evaluated a program to promote improved decision-making among youth within one local school district using a pre- and post-test design. They sampled a large number of students in the program using a non-probability purposive method of selecting students who had been identified initially as most at-risk for problem behaviors. They found that these students did not report better decision making after going through the program. In writing the report, they concluded that the program was a failure, and thus, should not be continued in this school district or replicated by surrounding school districts. Based on the information provided, this is an example of what common mistake made in evaluation reports