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Accurate characterization of the resistance to contact normal force relationship for a given contact system is critical in determining the reliability of that system. Since little is known of a contact system in its early development, sampling techniques are required to characterize resistance to normal force relationship. Though most models address relationships between mean values of resistance and normal force, the parameter of interest is in actuality the highest allowable resistance for a given normal force. Techniques are offered to assist the examiner in defining appropriate sample sizes to characterize the variance in contact resistance, and to detect differences in contact resistance at various normal forces. In addition, tradeoffs are discussed related to the selection of sample size with respect to sensitivity gained or lost as well as the likelihood of falsely characterizing a relationship. Finally, a method for modeling the entire resistance vs. normal force curve is offered through the collection of statistics acquired via sampling techniques.