An in vitro study of the accuracy and precision of Breathalyzer models 900, 900A, and 1000

Ninety Breathalyzer instruments (Model 1000) and twenty instruments (Models 900, 900A) were studied using a protocol described by the Department of Transportation's "Standard for Devices to Measure Breath Alcohol." Although the mean of each of three concentrations tested (0.05, 0.10, and 0.15 g/210 L) compared favorably in both series, the standard deviation was consistently higher for the Model 1000 instruments. The Model 1000 instruments also produced a significant number of test results which exceeded the normally expected scientific deviation.     

Commonly overlooked dimensions of employee selection

Most failures on the job are not due to lack of skills or ability. Therefore, according to psychologist Witkin, the employee selection process must also consider such factors as employee motivation, past performance, potential for failure, the emotional demands of the job, and the proper use of testing tools.