Abstract

What one cannot measure one cannot control. Measurement plays a key role in science, technology and industry. Where there are measurements there is associated errors. Study of measurement errors has a long history. Attempts have been made to classify and understand the factors that contribute to errors in measurement. The understanding of this is useful for error reduction and also providing the margin for errors and reducing damage caused due to errors. For the purpose of classification and study, measurement errors have been divided into instrument error, method error and human error. The former two are easier to study and correct, but the later is less understood. In this study an attempt has been made to study the effect of selected work related variables on human errors in observing and noting measurements which contribute to measurement errors. In a measuring system, though some of the effects of variables on measurement errors can be guessed, only an experimental study will be able to isolate, quantify and present the effect of each variable separately. Hence an experimental study was designed and conducted to quantify and present the effect of selected work related variables of two sets of human subjects used in the experiments.  Analysis of the results revealed that the variables identified and studied have significant effect on measurement errors, and their effects were also separately quantified. This will be of use to professionals trying to reduce measurement errors, especially in industrial environments, where knowing the variables and the extent of error they induce, appropriate work related settings can be adopted to keep human errors within the tolerable limits.

Key words: Measurement error, test type differences, instrument differences, time of work, time pressure, environment.