Open Access

Table 1

Comparison between the mean Cronbach’s alpha values for each quality of the original data and the 50th and 95th percentile (in parenthesis) Cronbach’s alpha values based on 1000 collections of randomly permuted data for each of the 56 time series. All Cronbach’s alpha values were deemed statistically significant since they exceeded the 95th percentile of the 1000 unrelated collections.

Cronbach’s alpha
Brightness Roughness Mass Tension
Original data .65 .85 .69 .89
Random permutation −.03 (.08) −.03 (.08) −.03 (.08) −.03 (.07)

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