# NavList:

## A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

**Re: Cocked hats, again.**

**From:**Gary LaPook

**Date:**2007 Mar 14, 21:22 -0700

Gary LaPook wrote: Indeed I do assume that the sigma is the same for large and small triangles. Sigma is based on the method of observation and the randomness of the factors that effect the observations, waves, hazy horizon, etc. Sometimes the random errors have the same sign and you get a large triangle and sometimes the signs are different and you get a smaller triangle, this is the nature of random errors even though sigma remains the same. Fred Hebard wrote: >Gary, > >The size of the Gaussian bell curve, or whatever curve, around each >position line wouldn't affect the probability of being on one side or >another; as long as the curve is symmetrical the probability would >still be one half. The triangle is merely at the intersection of the >lines; another of our assumptions are that the errors for each line >are independent (and, for some calculations, equal). A small >triangle suggests that sigma is small for each line, and a large >triangle that sigma is large. You appear to be assuming sigma is the >same size for different sized triangles. > > --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To unsubscribe, send email to NavList-unsubscribe@fer3.com -~----------~----~----~----~------~----~------~--~---