4. Chapter Summary

Unlike the Brute Force approach, Direct Minimization does not require determining each possible elevation before computing averages. This method requires only that  appropriate observation equations are constructed and partial derivatives taken with respect to each unknown. It's more flexible than Brute Force, but can still be improved on. For example, determining uncertainties for adjusted values and observations is, frankly, a pain. Fortunately, there's a systematic approach that addresses deficiencies of Brute Force and Direct Minimization.