Land Surveyors United

Least Squares Adjustment

Interactive guide to understanding and applying least squares adjustment in surveying

Simulation Controls

3 5 20

Design Matrix Input

A Matrix (Design Matrix)

L Vector (Observations)

P Matrix (Weights)

Adjustment Results

Observations Residuals

Parameter Estimates

Quality Indicators

Error Ellipses

Least Squares Theory

Normal Equations

(ATPA)x = ATPL

Parameter Solution

x = (ATPA)-1ATPL

Residuals

v = Ax - L

Statistical Analysis

Chi-Square Test

Data Snooping