Hello Guys
can someone explain to me in simple terms how adjustments are made using least squares
Bow ditch distributes the misclose evenly over traverse nice and easy
so how does least squares do it and is it the most accurate method??
im just working through my studies today as we are really quiet with not much work on
any help work be great
Thanks guys
Mat
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Replies
least square adjustment is a method of how to analyze and adjust survey measurement in order to obtain minimum corrections on survey measurement. If the survey conducted with minimum errors, the corrections should be minimum and distributed as normal distribution. Statistic analysis can be carried out to accept or reject the these corrections. In the least square method, instrument accuracy is considered in calculation
Hello Mat
Least squares adjustments is a very powerful thing. But quit complicated to explain. See this...http://www.surveying.unsw.edu.au/ls/l1_norm.pdf
Least square method can additionally used as a planning tool (before measurements are conducted). Just to see how geometry affects the precision of every coordinate. I wrote an android App which allows you to calculate quickly different networks arrangments (including traverses) .
https://play.google.com/store/apps/details?id=bestnetwork.com.blogspot.geomtours
or see the free version for resections:
https://play.google.com/store/apps/details?id=besttachyspot.com.blogspot.geomtours
I logged in this morning to this EXACT question.
I look forward to someone offering some opinions. I am unsure what exactly the difference is and when I should use one over the other?
Thanks guys.
No specialist but I will attempt a reply.
Bowditch Adjustment only requires one angular reading and one distance reading per station.
Least Squares Adjustment requires several angular and distance readings per station.
systematic reading errors from preceeding stations accumulate as the traverse progresses.
The Least Squares method applies probability theory to eliminate the most significant errors in the resulting co-ordinates and provides a best fit solution for the traverse.
Not a simple explanation but read the following:-
Penn State freedownloads
http://downloadpdfz.com/pdf/traverse-computations-pdf
Royal Melbourne Institute of Technology
http://user.gs.rmit.edu.au/rod/files/publications/Travad.pdf
Barry Graham
Melbourne, Australia