精选优质文档-倾情为你奉上Section 2 The Reliability of a Survey and Errors测量误差的可靠性Since every technique of measurement is subject to unavoidable error, surveyors must be aware of all sources and types of error and how they combine. If the accuracy of a measurement is defined as the nearness of that value to its true value (a quantity we can never know) then a surveyor must ensure that the techniques he chooses will produce a result that is sufficiently accurate. He must know, therefore, how accurat