Hi all,

For an interoberver study I determined the Krippendorff’s alpha with bootstrap interval for 2 equally sized groups with the following macro for SPSS: http://afhayes.com/spss-sas-and-r-macros-and-code.html.

I was wondering how I can calculate the difference with corresponding bootstrapped confidence interval and p-value between these 2 groups. As far as I’m aware of SPSS does not have a separate function to calculate this. See below my example with the bootstrap at 1000.

Group 1: 0.41 (95% CI, 0.35 – 0.48) (Bootstrap number of resamples = 1000)

Group 2: 0.69 (95% CI, 0.58 – 0.76) (Bootstrap number of resamples = 1000)

Difference: 0.69 – 0.41 = 0.28

Bootstrapped confidence interval of difference =? p-value =?

Thanks so much for your help and advice!