In geodesy, reliable results are obtained with quality observations and the corresponding mathematical and stochastic models. One establishes if individual criteria and requirements during the measurement and calculation procedures are met by evaluating and testing typical parameters respectively -- procedures of statistical hypothesis testing being indispensable part of the process. In deformation analysis, statistical tests are applied for testing the assumptions about the parameters, for assessing the conformity of observations and the mathematical model, for detecting of gross errors in observations for identifying the conformity of allegedly fixed points between the epochs and for determining the points with statistically typical displacements. For the processing of quality measurement data, the task of a surveyor is to use a correct and reliable mathematical model, which provides a high degree of confidence in the results and reduces a client's risk. Methods of statistical hypothesis testing help experts to make decisions, but it is not possible to use them to replace measurement and calculation procedures in geodesy.