Thread: Testing a conventional approach to load development

Originally Posted by gimp

These groups represent a reasonable picture of the precision of the system with these loads. Even with 20rd the statistical power is limited - in the world of statistics, 20 samples is a small amount when you are trying to detect small differences between means with relatively large standard deviations. However with 20rd groups and the difference in mean between these loads we do have power to detect the difference, and it is a significant difference at the 95% confidence level.

@gimp I don't doubt your results but out of interest.

Questions;
How were you able to determine the location of each shot to obtain each shot location and radius? Looks difficult to do for the targex group unless this is was a group derived from multiple overlapping targets.
To assess significance are you visually comparing mean radius and 95% CI error bars or running a statistical test?

Are you able to provide standard deviations or raw data? I'd be interested in having a play and work out statistical power and effect size to give us an estimate of what your sample size would have to be to confidently detect a group that is over 50% bigger than another? I suspect very few shots when the difference is >50%. I do warn though that detecting the difference between two groups is different from understanding the precision of a single load.