Competitive Aggressiveness Entrepreneurial Orientation
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Vehkalahti, Puntanen, Tarkkonen 2006 define reliability as the ratio of the true variance to the total variance of the measurement, which does not include the variance of the
random measurement error. There are two reliability tests, namely Composite Reliability and Cronchbach’s alpha. Both Composite Reliability and Cronbach’s alpha have similarity.
Secondly, both measurements vary from 0 to 1 and value larger than 0.6 are considered as accepted reliability. The reason lies behind the similarity measurement level refers to the ratio
of the true variable to the total variance of measurement.
If we take a look at the formulas of CR and Cronbach’s alpha, it appears that
Composite reliability focus on loading of indicator variable and error variable, while Cronbach’s alpha consider variance of indicator i. Cronbach alpha is individual item
reliability, while composite reliability examines the construct or latent variable. Cronbach’s alpha is a traditional reliability measure under the assumption that all factor loadings are
constrained to be equal, and all error variances are constrained to be equal. Raykov 1998 indicates that Cronbach alpha may over-or underestimate reliability. This may become
serious when the test is multi-dimensional. Then, CR is developed to deal with multi- dimensional data.
The λ represents the loading of indicator variable of i from a latent variable, ε
i
represents error of variable i, and j is the flow index across all reflective measurement models. N is the number of indicators assigned to the factor, σ is variance of indicator i.
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