4. assumption of homoscedasticity.
homoscedasticity means that the variance of errors the same across all levels of the IV. When the variance of error differs at different values of the IV, homoscedasticity is indicated. According to Berry and Feldman and Tabachnick and Fidell slight homoscedasticity. has little effect on significance tests; however, when homoscedasticity is marked it can lead to serious distortion of findings and seriously weaken the analysis thus increasing the possibility of a typs 1 error. this assumption can be checked by the regression standardized predicted value.