First of all, the Grambsch and Therneau tests were developed in a medical context where sample sizes are generally less than one hundred, making the test insensitive to minor irregularities. For sample sizes as large as those in this study, small confidence intervals give significant p values, even if the data show negligible anomalies. In addition to formal tests, it is therefore recommended to conduct a visual examination of the residues of Schonfeld. Footnote 127 Such a visual investigation does not result in significant violations of proportional risk acceptance for one of the material covariates and a violation only for a handful of countries with which the United States generally has few agreements, such as Burma, Ecuador or New Caledonia. The corresponding charts are included in the online appendix. 52 Martin believes that the cost differential for the difference between executive and exclusive contracts is the largest, but it extends its argument to the difference between the executive agreements of Congress and the treaties. See Martin, supra note 15, at 447. A treaty is an international agreement established in writing and by international law between two or more sovereign states, whether inscribed in a single instrument or in two or more related acts. Treaties have many names: conventions, agreements, pacts, pacts, charters and statutes, among others. The choice of name has no legal value. Contracts can generally be categorized into one of two main categories: bilateral (between two countries) and multilateral (between three or more countries). For example, 85 commentators have observed recent efforts by developing countries to amend, replace or withdraw bilateral investment agreements (ILOs) with the United States.
These efforts are fuelled by information on the negative national effects of TDT and interpretations of contracts that tend to favour investors. For an in-depth discussion, see Lavopa, Federico M., Barreiros, Lucas E. Bruno, Victoria M., How to Kill a BIT and Not Die Trying: Legal and Political Challenges of Denouncing or Renegotiating Bilateral Investment Treaty, 16 J. Int`l Econ. L. 869 (2013). The use of shelf life as a substitute for force of use is justified for three reasons.