2.3.2.2 Search for errors using the residuals
If the convergence limit has been reached, a search for errors can be made (after iteration is finished) by the residuals v of the observations. The number of stars of a residual corresponds to the integer part of the expression
Since an individual gross error affects all residuals (according to (2.3.1/1)), first only the largest errors must be eliminated. In the next adjustment many residuals will then be smaller. If all well-detectable larger errors 
have thus been eliminated, the option for data-snooping should be activated.