Interaction effect analysis of selected factors on safe weight model

Abstract

A mathematical model was developed by means of norm of strain energy to limit manual weight. The main effect interaction of the factors had been studied. However, Two-ways Interaction Effect (TIE) of the selected factors were not yet studied. Age, body-weight, stature-change, vertebra-length, lift-frequency, and varying workshop temperature were chosen factors on biomechanical, physiological and psychophysical basis. This study analysed TIE of the selected factors. The selected factors data were gotten by ZT-160 scale, stadiometer, tape-rule, stop-clock and RH/Temperature pen from fifty practising male manual construction workers selected using purposive sampling. The data were inputted into Excel and SPSS to analysis TIE through Multiple Linear Regression (MLR) and ANOVA at 0.05. The MLR investigation of TIE of the parameters shows that interactions between age and body-weight or stature-change, temperature and body-weight or stature-change, stature-change and lift-frequency or body-weight or vertebra-length, body-weight and lift-frequency or vertebra-length were significant (p=0.00), while between body-weight and stature-change gave highest R²=0.81. ANOVA revealed that interactions between age and vertebra-length, temperature and vertebra-length, body-weight and stature-change remained significant p=0.02, 0.02, and 0.00 with F-test=2.80, 7.25 and 12.14, respectively. Hence, body-weight and stature-change interaction shows highest effect of the two-ways interaction of the selected factors.