Alkhadim Ghadah S
Department of Psychology, College of Arts, Taif University, Taif, Saudi Arabia.
Front Psychol. 2022 Feb 10;13:815490. doi: 10.3389/fpsyg.2022.815490. eCollection 2022.
The purpose of the present study was to address the shortcomings of Cronbach's alpha concerning the semantic overlap between items. Using an example from a motivational measure, the correction of Cronbach's alpha was applied by partialing out the effects due to conceptual overlap. The significance of Cronbach's alpha was tested using simulated random data derived from the measure and by estimating the confidence intervals with known and unknown distributions. The results indicated that the uncorrected conceptual overlap coefficient alpha was equal to 0.89 and 0.66 following the correction. After simulating the corrected statistical results, the distribution of alpha with random numbers had an estimate of 95%, equal to 0.41. The lower bound of the corrected alpha distribution was equal to 0.41, suggesting that the corrected alpha could easily belong to the distribution of alpha developed from simulated random numbers. Thus, the semantic overlap between items on a measure represents a significant threat to the validity of the alpha coefficient.
本研究的目的是解决克朗巴哈系数在项目间语义重叠方面的不足。以一项动机测量为例，通过排除概念重叠的影响来应用克朗巴哈系数的校正。使用从该测量中得出的模拟随机数据，并通过估计已知和未知分布的置信区间来检验克朗巴哈系数的显著性。结果表明，未校正的概念重叠系数α为0.89，校正后为0.66。模拟校正后的统计结果后，α随随机数的分布估计有95%等于0.41。校正后α分布的下限等于0.41，这表明校正后的α很可能属于由模拟随机数得出的α分布。因此，测量项目间的语义重叠对α系数的有效性构成了重大威胁。
