Sample Statistics Research Paper on Underpinnings of Cronbach’s Alpha

Cronbach is a research finding that has brought many questions to the table to prove its existence and be able to work with it in the future. This proofing is brought about by several misconceptions about the ideas of the score reliability and lack of understanding of the original concept. A shared mistake is that reliability score is a representative of a test or a dimensional tool; though, reliability score is a characteristic of results (Tavakol and Dennick, 2011).

Cronbach’s alpha is defined as a measure of uniformity, as revealed by how items from a group are closely related. It measures the scale reliability. Cronbach’s alpha states that when a measure of internal consistency is high, it does not mean that the unit measured is unidimensional. If the scale in question is unidimensional, then it must be supported with evidence, which includes analyses of tests to estimate the scale’s consistency (Green et al., 1997). Therefore, the alpha is regarded as a coefficient of reliability, which is inscribed as a function of the calculated sum of test components and average intercorrelation among the tested elements. The formula below is a standardised Cronbach’s alpha formulation of its coefficient (Tavakol and Dennick, 2011).


From the coefficient formula above, N is an equal number of tested items, c-bar is average inter-component correlation covariance amongst the elements as well as v-bar which is the average variance. Over the years, Cronbach’s alpha has undergone a lot of rectification and improvements to come up with a standardised formula for calculating its coefficient. The improvement action led to many researcher’s interventions to prove the properties of the alpha and rectify the misconceptions. The research bore result which included some ratio variance formula development. The examples being adapted from Thompson (2003) and Henson (2001).


Work Cited

Green, S.B., Lissitz, R.W. and Mulaik, S.A., 1977. Limitations of coefficient alpha as an index of test unidimensionality1. Educational and Psychological Measurement37(4), pp.827-838.

Henson, R.K., 2001. Understanding internal consistency reliability estimates: A conceptual primer on coefficient alpha. Measurement and evaluation in counselling and development34(3), p.177.

Tavakol, M. and Dennick, R., 2011. Making sense of Cronbach’s alpha. International journal of medical education2, p.53.

Thompson, B., 2003. Understanding reliability and coefficient alpha. Score reliability: Contemporary thinking on reliability issues, pp.3-23.