...
- Histogram of difference in Avg(ping-RTT)-Avg(nping-RTT) for IPv6 measured from China
- Histogram of the relative difference between ping and nping RTTs measured from China
- Cumulative Distribution Frequency of the Avg(ping-RTT) and Avg(nping-RTT) with the differences.
The maximum(abs(Difference))=D is 0.031. We use the Kolmogorov Smirnov two sample test. for the number of observations (N), c(alpha) > D/sqrt(2N/N*N), where alpha indicates that the probability of rejecting the null hypothesis (the null hypothesis says there is no relationship between the two measured phenomena) is 85%.
Also see http://www-iepm.slac.stanford.edu/~cottrell/pinger/synack/ping-vs-synack.html